XRT83VSH28
8-CHANNEL E1 SHORT-HAUL LINE INTERFACE UNIT
MARCH 2010
REV. 2.0.0
GENERAL DESCRIPTION
The on-chip clock synthesizer generates an E1 clock
reference.
The XRT83VSH28 is a fully integrated 8-channel
short-haul line interface unit (LIU) that operates from
a 1.8V and a 3.3V power supply. Using internal
termination, the LIU provides one bill of materials to
operate in E1 75 or 120 mode with minimum
external components. The LIU features are
programmed through a standard parallel or serial
microprocessor interface. EXAR’s LIU has patented
high impedance circuits that allow the transmitter
outputs and receiver inputs to be high impedance
when experiencing a power failure or when the LIU is
powered off. Key design features within the LIU
optimize 1:1 or 1+1 redundancy and non-intrusive
monitoring applications to ensure reliability without
using relays.
Additional features include RLOS, a 16-bit LCV
counter for each channel, AIS, QRSS generation/
detection, TAOS, DMO, and diagnostic loopback
modes.
APPLICATIONS
ISDN Primary Rate Interface
CSU/DSU E1 Interface
E1 LAN/WAN Routers
Public switching Systems and PBX Interfaces
E1 Multiplexer and Channel Banks
FIGURE 1. BLOCK DIAGRAM OF THE XRT83VSH28 E1 LIU (HOST MODE)
MCLKE1
MCLKOUT
MASTER CLOCK SYNTHESIZER
1 of 8 channels, CHANNEL_n
TPOS_n/ TDATA_n
TNEG_n/ CODES_n
TCLK_n
QRSS
PATTERN
GENERATOR
DRIVE
MONITOR
TAOS
HDB3/
TX/ RX JITTER
ATTENUATOR
ENCODER
Remote
Loopback
TIMING
CONTROL
TX FILTER
& PULSE
SHAPER
Digital
Loopback
DMO_n
TTIP_n
LINE
DRIVER
TRING_n
TXON_n
Analog
Loopback
QRSS
DETECTOR
RCLK_n
RNEG_n/ LCV_n
RPOS_n/ RDATA_n
HDB3/
DECODER
TIMING &
DATA
RECOVERY
TX/ RX JITTER
ATTENUATOR
LOS
DETECTOR
RTIP_n
PEAK
DETECTOR
& SLICER
RRING_n
AIS
DETECTOR
RLOS_n
HW/ HOST
WR_R/W
RD_DS
ALE- AS
CS
RDY_ DTACK/ SDO
INT
SER_ PAR
TEST
MICROPROCESSOR
/ SERIAL INTERFACE CONTROLLER
ICT
PTS1
PTS2
D[7:0]
PCLK/ SCLK
A[7:0]/ SDI
RESET
Exar Corporation 48720 Kato Road, Fremont CA, 94538 • (510) 668-7000 • FAX (510) 668-7017 • www.exar.com
XRT83VSH28
8-CHANNEL E1 SHORT-HAUL LINE INTERFACE UNIT
REV. 2.0.0
FIGURE 2. BLOCK DIAGRAM OF THE XRT83VSH28 E1 LIU (HARDWARE MODE)
MCLKE1
MCLKOUT
TAOS_n
MASTER CLOCK SYNTHESIZER
1 of 8 channels, CHANNEL_n
TPOS_n/ TDATA_n
TNEG_n/ CODES_n
TCLK_n
QRSS
PATTERN
GENERATOR
DRIVE
MONITOR
TAOS
HDB3/
TX/ RX JITTER
ATTENUATOR
ENCODER
Remote
Loopback
TIMING
CONTROL
Digital
Loopback
TX FILTER
& PULSE
SHAPER
DMO_n
TTIP_n
LINE
DRIVER
TRING_n
Analog
Loopback
TXON_n
QRSS
DETECTOR
RCLK_n
RNEG_n/ LCV_n
RPOS_n/ RDATA_n
HDB3/
DECODER
TIMING &
DATA
RECOVERY
TX/ RX JITTER
ATTENUATOR
LOS
DETECTOR
PEAK
DETECTOR
& SLICER
RTIP_n
RRING_n
LOOP1_n
LOOP0_n
AIS
DETECTOR
RLOS_n
HW/ HOST
GAUGE
JASEL1
JASEL0
RXTSEL
TXTSEL
TERSEL
RXRES0
RXRES1
TEST
HARWARE CONTROL
2
ICT
RESET
TRATIO
SR/ DR
EQC[4:0]
TCLKE
RCLKE
RXMUTE
ATAOS
XRT83VSH28
8-CHANNEL E1 SHORT-HAUL LINE INTERFACE UNIT
REV. 2.0.0
FEATURES
Fully integrated eight channel short-haul transceivers for E1 (2.048MHz) applications
Internal Impedance matching on both receive and transmit for 75 (E1) and 120 (E1) applications are per
port selectable through software without changing components
Power down on a per channel basis with independent receive and transmit selection
User programable Arbitrary Pulse mode
On-Chip transmit short-circuit protection and limiting protects line drivers from damage on a per channel
basis
Selectable Crystal-Less digital jitter attenuators (JA) with 32-Bit or 64-Bit FIFO for the receive or transmit
path
Driver failure monitor output (DMO) alerts of possible system or external component problems
Transmit outputs and receive inputs may be "High" impedance for protection or redundancy applications on a
per channel basis
Support for automatic protection switching
1:1 and 1+1 protection without relays
Receive monitor mode handles 0 to 6dB resistive attenuation (flat loss) along with 0 to 6dB cable loss
Loss of signal (RLOS) according to ITU-T G.775/ETS300233 (E1)
Programmable data stream muting upon RLOS detection
On-Chip HDB3 encoder/decoder with an internal 16-bit LCV counter for each channel
On-Chip digital clock recovery circuit for high input jitter tolerance
QRSS/PRBS pattern generator and detection for testing and monitoring
Error and bipolar violation insertion and detection
Transmit all ones (TAOS) Generators and Detectors
Supports local analog, remote, digital, and dual loopback modes
Supports gapped clocks for mapper/multiplexer applications
1.8V Inner Core
3.3V I/O Supply Operation
225 ball BGA package
-40°C to +85°C Temperature Range
ORDERING INFORMATION
PART NUMBER
PACKAGE
OPERATING TEMPERATURE RANGE
XRT83VSH28IB
225 Ball BGA
-40°C to +85°C
3
4
RVDD
2
TCK
TVDD
TDI
RRING_4
RTIP_4
DVDD1v8
1
P
R
T
U
V
TVDD
DMO_5
TRING_5
DMO_4 TAOS_7
TCLK_4 RNEG_4 TCLK_5 TAOS_4
TGND
TGND
RVDD
RPOS_5 RNEG_5
RVDD
Reserved
3
4
5
6
7
D[5]
8
D[4]
D[2]
RESET
DGND
DGND
A[0]
A[2]
A[1]
9
D[3]
D[1]
DGND
TXON_0 JASEL0 TCLK_2 RLOS_3 RCLK_3 DVDD3v3
10
RXRES0
11
TXTSEL
DVDD1v8 RXTSEL
12
ICT
TEST
RVDD
TVDD
TRING_3
RVDD
TTIP_3
INT
RXON
µPTS1
TVDD
TVDD
TGND
TGND
14
15
GAUGE
RNEG_2
RTIP_2
RVDD
RGND
RPOS_6
NC
RRING_6
RTIP_6
AVDDS DVDD1v8
AGND
DGND
RGND
DMO_6
RPOS_7
RGND
16
17
TXON_4 DMO_7 TPOS_6 TCLK_6 RNEG_7
TXON_5 TNEG_6 TCLK_7 RCLK_7
13
JTAGTip
RRING_3
RTIP_3
TTIP_2 RRING_2
TVDD
RGND
TGND
18
DGND
RVDD
RTIP_7
RRING_7
TTIP_7 TRING_7 SER_PAR
TTIP_6
RCLK_6 RNEG_6
µPTS2
DVDD3v3
RLOS_6
RLOS_2 RCLK_2
DGND
TRING_2
TGND
TXON_1 TNEG_2 TPOS_3 RPOS_2
TXON_2 DMO_3 TCLK_3 DMO_2
TX0N_3 JASEL1 TPOS_2 TNEG_3 RNEG_3 RPOS_3 JTAGRing
A[7]
TERSEL TXON_6 TXON_7 TNEG_7 TRING_6
A[4]
A[5]
A[6]
A[3]
HW_HOST Reserved RXMUTE µPCLK TPOS_7 RLOS_7
DVDD3v3 RXRES1
225 Ball BGA
(Top View)
XRT83VSH28
DVDD3v3 DVDD1v8
DGND
DGND
Reserved DVDD1v8
8-CHANNEL E1 SHORT-HAUL LINE INTERFACE UNIT
RLOS_4 TPOS_4 TNEG_5 TAOS_6
D[6]
D[7]
D[0]
DMO_0 TAOS_0 WR_R/W
RPOS_4 RCLK_4 TNEG_4 TPOS_5 TAOS_5
RGND
TTIP_4
TRING_4
TTIP_5
RGND
AGND
SR/DR
DVDD3v3
N
AGND
AVDD
RLOS_5 RCLK_5
DGND
AVDD
RRING_5
TTIP_1
M
RGND
TVDD
RTIP_5
RPOS_1
TRING_1
L
RTIP_1
G
TGND
TVDD
DMO_1
Reserved
RRING_1
F
TRING_O TTIP_0
TGND
K
TMS
E
RGND
CS
ALE
RLOS_0 TNEG_0 TPOS_0 TAOS_3 RD_DS Reserved
MCLKE1
RRING_0
D
RVDD
J
RTIP_0
C
RDY
RPOS_0 RCLK_0 TCLK_0 TNEG_1 TAOS_1
MCLKOUT RNEG_1 RCLK_1 RLOS_1
TDO
B
RNEG_0 TCLK_1 TPOS_1 TAOS_2
H
DGND
A
XRT83VSH28
REV. 2.0.0
XRT83VSH28
REV. 2.0.0
8-CHANNEL E1 SHORT-HAUL LINE INTERFACE UNIT
GENERAL DESCRIPTION................................................................................................. 1
APPLICATIONS ............................................................................................................................................... 1
FIGURE 1. BLOCK DIAGRAM OF THE XRT83VSH28 E1 LIU (HOST MODE)........................................................................................ 1
FIGURE 2. BLOCK DIAGRAM OF THE XRT83VSH28 E1 LIU (HARDWARE MODE) ............................................................................... 2
FEATURES ..................................................................................................................................................... 3
ORDERING INFORMATION .................................................................................................................... 3
PIN DESCRIPTION BY FUNCTION................................................................................... 5
RECEIVE SECTION ......................................................................................................................................... 5
TRANSMIT SECTION ....................................................................................................................................... 8
PARALLEL MICROPROCESSOR INTERFACE..................................................................................................... 10
JITTER ATTENUATOR .................................................................................................................................... 12
................................................................................................................................................................... 13
CLOCK SYNTHESIZER ................................................................................................................................... 13
ALARM FUNCTIONS/REDUNDANCY SUPPORT ................................................................................................. 14
SERIAL MICROPROCESSOR INTERFACE ......................................................................................................... 16
POWER AND GROUND .................................................................................................................................. 16
FUNCTIONAL DESCRIPTION ......................................................................................... 19
1.0 HARDWARE MODE VS HOST MODE ................................................................................................ 19
1.1 FEATURE DIFFERENCES IN HARDWARE MODE ...................................................................................... 19
TABLE 1: DIFFERENCES BETWEEN HARDWARE MODE AND HOST MODE .......................................................................................... 19
2.0 RECEIVE PATH LINE INTERFACE .................................................................................................... 20
FIGURE 3. SIMPLIFIED BLOCK DIAGRAM OF THE RECEIVE PATH ...................................................................................................... 20
2.1 LINE TERMINATION (RTIP/RRING) .............................................................................................................. 20
2.1.1 CASE 1: INTERNAL TERMINATION.......................................................................................................................... 20
TABLE 2: SELECTING THE INTERNAL IMPEDANCE ............................................................................................................................. 20
FIGURE 4. TYPICAL CONNECTION DIAGRAM USING INTERNAL TERMINATION .................................................................................... 20
2.1.2 CASE 2: INTERNAL TERMINATION WITH ONE EXTERNAL FIXED RESISTOR FOR ALL MODES .................... 21
TABLE 3: SELECTING THE VALUE OF THE EXTERNAL FIXED RESISTOR ............................................................................................. 21
FIGURE 5. TYPICAL CONNECTION DIAGRAM USING ONE EXTERNAL FIXED RESISTOR ....................................................................... 21
2.2 CLOCK AND DATA RECOVERY ................................................................................................................... 22
FIGURE 6. RECEIVE DATA UPDATED ON THE RISING EDGE OF RCLK .............................................................................................. 22
FIGURE 7. RECEIVE DATA UPDATED ON THE FALLING EDGE OF RCLK ............................................................................................ 22
TABLE 4: TIMING SPECIFICATIONS FOR RCLK/RPOS/RNEG .......................................................................................................... 22
2.2.1 RECEIVE SENSITIVITY .............................................................................................................................................. 23
FIGURE 8. TEST CONFIGURATION FOR MEASURING RECEIVE SENSITIVITY ........................................................................................ 23
2.2.2 INTERFERENCE MARGIN ......................................................................................................................................... 23
FIGURE 9. TEST CONFIGURATION FOR MEASURING INTERFERENCE MARGIN .................................................................................... 23
2.2.3 GENERAL ALARM DETECTION AND INTERRUPT GENERATION ........................................................................ 23
2.3 RECEIVE JITTER ATTENUATOR .................................................................................................................. 24
2.4 HDB3 DECODER ............................................................................................................................................ 25
2.5 RPOS/RNEG/RCLK ........................................................................................................................................ 25
FIGURE 10. SINGLE RAIL MODE WITH A FIXED REPEATING "0011" PATTERN ................................................................................... 25
FIGURE 11. DUAL RAIL MODE WITH A FIXED REPEATING "0011" PATTERN ...................................................................................... 25
2.6 RXMUTE (RECEIVER LOS WITH DATA MUTING) ....................................................................................... 26
FIGURE 12. SIMPLIFIED BLOCK DIAGRAM OF THE RXMUTE FUNCTION ............................................................................................ 26
3.0 TRANSMIT PATH LINE INTERFACE ................................................................................................. 27
FIGURE 13. SIMPLIFIED BLOCK DIAGRAM OF THE TRANSMIT PATH ................................................................................................... 27
3.1 TCLK/TPOS/TNEG DIGITAL INPUTS ............................................................................................................ 27
FIGURE 14. TRANSMIT DATA SAMPLED ON FALLING EDGE OF TCLK ............................................................................................... 27
FIGURE 15. TRANSMIT DATA SAMPLED ON RISING EDGE OF TCLK ................................................................................................. 27
TABLE 5: TIMING SPECIFICATIONS FOR TCLK/TPOS/TNEG ........................................................................................................... 28
3.2 HDB3 ENCODER ............................................................................................................................................ 28
TABLE 6: EXAMPLES OF HDB3 ENCODING ...................................................................................................................................... 28
3.3 TRANSMIT JITTER ATTENUATOR ............................................................................................................... 29
TABLE 7: MAXIMUM GAP WIDTH FOR MULTIPLEXER/MAPPER APPLICATIONS .................................................................................... 29
3.4 TAOS (TRANSMIT ALL ONES) ..................................................................................................................... 29
FIGURE 16. TAOS (TRANSMIT ALL ONES)...................................................................................................................................... 29
3.5 TRANSMIT DIAGNOSTIC FEATURES .......................................................................................................... 29
3.5.1 ATAOS (AUTOMATIC TRANSMIT ALL ONES)......................................................................................................... 29
FIGURE 17. SIMPLIFIED BLOCK DIAGRAM OF THE ATAOS FUNCTION............................................................................................... 30
3.5.2 QRSS GENERATION.................................................................................................................................................. 30
I
XRT83VSH28
8-CHANNEL E1 SHORT-HAUL LINE INTERFACE UNIT
REV. 2.0.0
TABLE 8: RANDOM BIT SEQUENCE POLYNOMIALS ........................................................................................................................... 30
3.6 DMO (DIGITAL MONITOR OUTPUT) ............................................................................................................. 31
3.7 LINE TERMINATION (TTIP/TRING) ............................................................................................................... 31
FIGURE 18. TYPICAL CONNECTION DIAGRAM USING INTERNAL TERMINATION ................................................................................... 31
4.0 E1 APPLICATIONS ..............................................................................................................................32
4.1 LOOPBACK DIAGNOSTICS .......................................................................................................................... 32
4.1.1 LOCAL ANALOG LOOPBACK .................................................................................................................................. 32
FIGURE 19. SIMPLIFIED BLOCK DIAGRAM OF LOCAL ANALOG LOOPBACK ......................................................................................... 32
4.1.2 REMOTE LOOPBACK ................................................................................................................................................ 32
FIGURE 20. SIMPLIFIED BLOCK DIAGRAM OF REMOTE LOOPBACK .................................................................................................... 32
4.1.3 DIGITAL LOOPBACK ................................................................................................................................................. 33
FIGURE 21. SIMPLIFIED BLOCK DIAGRAM OF DIGITAL LOOPBACK ..................................................................................................... 33
4.1.4 DUAL LOOPBACK ..................................................................................................................................................... 33
FIGURE 22. SIMPLIFIED BLOCK DIAGRAM OF DUAL LOOPBACK ........................................................................................................ 33
4.2 LINE CARD REDUNDANCY ........................................................................................................................... 34
4.2.1 1:1 AND 1+1 REDUNDANCY WITHOUT RELAYS .................................................................................................... 34
4.2.2 TRANSMIT INTERFACE WITH 1:1 AND 1+1 REDUNDANCY .................................................................................. 34
FIGURE 23. SIMPLIFIED BLOCK DIAGRAM OF THE TRANSMIT INTERFACE FOR 1:1 AND 1+1 REDUNDANCY ......................................... 34
4.2.3 RECEIVE INTERFACE WITH 1:1 AND 1+1 REDUNDANCY..................................................................................... 35
FIGURE 24. SIMPLIFIED BLOCK DIAGRAM OF THE RECEIVE INTERFACE FOR 1:1 AND 1+1 REDUNDANCY ........................................... 35
4.2.4 N+1 REDUNDANCY USING EXTERNAL RELAYS ................................................................................................... 36
4.2.5 TRANSMIT INTERFACE WITH N+1 REDUNDANCY ................................................................................................ 36
FIGURE 25. SIMPLIFIED BLOCK DIAGRAM OF THE TRANSMIT INTERFACE FOR N+1 REDUNDANCY ...................................................... 36
4.2.6 RECEIVE INTERFACE WITH N+1 REDUNDANCY ................................................................................................... 37
FIGURE 26. SIMPLIFIED BLOCK DIAGRAM OF THE RECEIVE INTERFACE FOR N+1 REDUNDANCY ........................................................ 37
4.3 POWER FAILURE PROTECTION .................................................................................................................. 38
4.4 OVERVOLTAGE AND OVERCURRENT PROTECTION ............................................................................... 38
4.5 NON-INTRUSIVE MONITORING .................................................................................................................... 38
FIGURE 27. SIMPLIFIED BLOCK DIAGRAM OF A NON-INTRUSIVE MONITORING APPLICATION............................................................... 38
5.0 MICROPROCESSOR INTERFACE ......................................................................................................39
5.1 SERIAL MICROPROCESSOR INTERFACE BLOCK (BGA PACKAGE ONLY) ........................................... 39
FIGURE 28. SIMPLIFIED BLOCK DIAGRAM OF THE SERIAL MICROPROCESSOR INTERFACE ................................................................. 39
5.1.1 SERIAL TIMING INFORMATION................................................................................................................................ 39
FIGURE 29. TIMING DIAGRAM FOR THE SERIAL MICROPROCESSOR INTERFACE ................................................................................ 39
5.1.2 24-BIT SERIAL DATA INPUT DESCRITPTION ......................................................................................................... 40
5.1.3 ADDR[7:0] (SCLK1 - SCLK8) ..................................................................................................................................... 40
5.1.4 R/W (SCLK9)............................................................................................................................................................... 40
5.1.5 DUMMY BITS (SCLK10 - SCLK16) ............................................................................................................................ 40
5.1.6 DATA[7:0] (SCLK17 - SCLK24) ................................................................................................................................. 40
5.1.7 8-BIT SERIAL DATA OUTPUT DESCRIPTION ......................................................................................................... 40
FIGURE 30. TIMING DIAGRAM FOR THE MICROPROCESSOR SERIAL INTERFACE ................................................................................ 41
TABLE 9: MICROPROCESSOR SERIAL INTERFACE TIMINGS ( TA = 250C, VDD=3.3V± 5% AND LOAD = 10PF) .................................. 41
5.2 PARALLEL MICROPROCESSOR INTERFACE BLOCK .............................................................................. 42
TABLE 10: SELECTING THE MICROPROCESSOR INTERFACE MODE ................................................................................................... 42
FIGURE 31. SIMPLIFIED BLOCK DIAGRAM OF THE MICROPROCESSOR INTERFACE BLOCK .................................................................. 42
5.3 THE MICROPROCESSOR INTERFACE BLOCK SIGNALS ......................................................................... 43
TABLE 11: XRT83VSH28 MICROPROCESSOR INTERFACE SIGNALS THAT EXHIBIT CONSTANT ROLES IN BOTH INTEL AND MOTOROLA MODES
43
TABLE 12: INTEL MODE: MICROPROCESSOR INTERFACE SIGNALS .................................................................................................... 43
TABLE 13: MOTOROLA MODE: MICROPROCESSOR INTERFACE SIGNALS ........................................................................................... 44
5.4 INTEL MODE PROGRAMMED I/O ACCESS (ASYNCHRONOUS) ............................................................... 45
FIGURE 32. INTEL µP INTERFACE SIGNALS DURING PROGRAMMED I/O READ AND WRITE OPERATIONS ............................................ 46
TABLE 14: INTEL MICROPROCESSOR INTERFACE TIMING SPECIFICATIONS ........................................................................................ 46
5.5 MOTOROLA MODE PROGRAMMED I/O ACCESS (ASYNCHRONOUS) .................................................... 47
FIGURE 33. MOTOROLA 68K µP INTERFACE SIGNALS DURING PROGRAMMED I/O READ AND WRITE OPERATIONS ............................ 48
TABLE 15: MOTOROLA 68K MICROPROCESSOR INTERFACE TIMING SPECIFICATIONS ........................................................................ 48
5.6 POWERPC 403 SYNCHRONOUS MODE: ..................................................................................................... 49
FIGURE 34. POWERPC 403 MODE TIMING - WRITE OPERATION ...................................................................................................... 49
TABLE 16 POWER PC403 MODE TIMING - WRITE OPERATION......................................................................................................... 49
FIGURE 35. POWERPC 403 MODE TIMING - READ OPERATION ....................................................................................................... 50
TABLE 17 POWER PC403 MODE TIMING - READ OPERATION .......................................................................................................... 50
5.7 MICROPROCESSOR INTERFACE TIMING - MCP860 SYNCHRONOUS MODE ........................................ 51
FIGURE 36. MPC86X MODE TIMING - WRITE OPERATION ............................................................................................................... 51
TABLE 18 MPC86X MODE TIMING - WRITE OPERATION.................................................................................................................. 51
TABLE 19 MPC86X TIMING INFORMATION - READ OPERATION ........................................................................................................ 52
II
XRT83VSH28
REV. 2.0.0
8-CHANNEL E1 SHORT-HAUL LINE INTERFACE UNIT
FIGURE 37. MPC86X MODE TIMING - READ OPERATION ................................................................................................................ 52
TABLE 20: MICROPROCESSOR REGISTER ADDRESS (ADDR[7:0]) ................................................................................................... 53
TABLE 21: MICROPROCESSOR REGISTER CHANNEL DESCRIPTION ................................................................................................... 53
5.8 CHANNEL CONTROL REGISTERS .............................................................................................................. 55
TABLE 22:
TABLE 23:
TABLE 24:
TABLE 25:
TABLE 26:
TABLE 27:
TABLE 28:
TABLE 29:
MICROPROCESSOR REGISTER 0X00H BIT DESCRIPTION ................................................................................................. 55
CABLE LENGTH SETTING ................................................................................................................................................ 56
MICROPROCESSOR REGISTER 0X01H BIT DESCRIPTION ................................................................................................. 56
MICROPROCESSOR REGISTER 0X02H BIT DESCRIPTION ................................................................................................. 57
MICROPROCESSOR REGISTER 0X03H BIT DESCRIPTION ................................................................................................. 58
MICROPROCESSOR REGISTER 0X04H BIT DESCRIPTION ................................................................................................. 59
MICROPROCESSOR REGISTER 0X05H BIT DESCRIPTION ................................................................................................. 60
MICROPROCESSOR REGISTER 0X06H BIT DESCRIPTION ................................................................................................. 61
5.9 GLOBAL CONTROL REGISTERS ................................................................................................................. 63
TABLE 30:
TABLE 31:
TABLE 32:
TABLE 33:
TABLE 34:
TABLE 35:
TABLE 36:
TABLE 37:
MICROPROCESSOR REGISTER 0X80H, BIT DESCRIPTION ................................................................................................ 63
MICROPROCESSOR REGISTER 0X81H, BIT DESCRIPTION ................................................................................................ 64
MICROPROCESSOR REGISTER 0X82H BIT DESCRIPTION ................................................................................................. 64
MICROPROCESSOR REGISTER 0X8CH BIT DESCRIPTION ................................................................................................. 65
MICROPROCESSOR REGISTER 0X8DH BIT DESCRIPTION ................................................................................................. 65
MICROPROCESSOR REGISTER 0X8EH BIT DESCRIPTION ................................................................................................. 66
MICROPROCESSOR REGISTER 0XFEH BIT DESCRIPTION ................................................................................................. 67
MICROPROCESSOR REGISTER 0XFFH BIT DESCRIPTION ................................................................................................. 67
6.0 ELECTRICAL CHARACTERISTICS ................................................................................................... 68
TABLE 38: ABSOLUTE MAXIMUM RATINGS....................................................................................................................................... 68
TABLE 39: DC DIGITAL INPUT AND OUTPUT ELECTRICAL CHARACTERISTICS .................................................................................... 68
TABLE 40: AC ELECTRICAL CHARACTERISTICS ............................................................................................................................... 68
TABLE 41: POWER CONSUMPTION .................................................................................................................................................. 69
TABLE 42: E1 RECEIVER ELECTRICAL CHARACTERISTICS ................................................................................................................ 69
TABLE 43: E1 TRANSMITTER ELECTRICAL CHARACTERISTICS .......................................................................................................... 70
PACKAGE DIMENSIONS................................................................................................................................. 71
225 BALL PLASTIC BALL GRID ARRAY (BOTTOM VIEW) ....................................................................... 71
(19.0 X 19.0 X 1.0MM)...................................................................................................................... 71
ORDERING INFORMATION ..................................................................................................................... 72
REVISIONS ............................................................................................................................................... 72
III
XRT83VSH28
8-CHANNEL E1 SHORT-HAUL LINE INTERFACE UNIT
REV. 2.0.0
PIN DESCRIPTION BY FUNCTION
RECEIVE SECTION
SIGNAL NAME
BGA
LEAD #
TYPE
DESCRIPTION
RXON
K16
I
Receiver On
Hardware Mode Only
This pin is used to enable the receivers for all channels. By default, the receivers
are turned ON in hardware mode. To turn the receivers OFF, pull this pin "Low".
NOTE: Internally pulled "High" with a 50k resistor.
RLOS0
RLOS1
RLOS2
RLOS3
RLOS4
RLOS5
RLOS6
RLOS7
C3
H4
H15
A16
V3
L2
J15
T15
O
RCLK0
RCLK1
RCLK2
RCLK3
RCLK4
RCLK5
RCLK6
RCLK7
B3
H3
H16
A17
U3
L3
M15
U16
O
RNEG/LCV0
RNEG/LCV1
RNEG/LCV2
RNEG/LCV3
RNEG/LCV4
RNEG/LCV5
RNEG/LCV6
RNEG/LCV7
A2
H2
H18
B16
T4
M4
M16
V17
O
RNEG/LCV_OF Output
In dual rail mode, this pin is the receive negative data output. In single rail mode,
this pin is a Line Code Violation / Counter Overflow indicator. If LCV is selected by
programming the appropriate global register and if a line code violation, a bi-polar
violation, or excessive zeros occur, the LCV pin will pull "High" for a minimum of one
RCLK cycle. LCV will remain "High" until there are no more violations. However, if
OF (Overflow) is selected the LCV pin will pull "High" if the internal LCV counter is
saturated. The LCV pin will remain "High" until the LCV counter is reset.
RPOS0
RPOS1
RPOS2
RPOS3
RPOS4
RPOS5
RPOS6
RPOS7
B2
G2
D15
B17
U2
M3
L17
T17
O
RPOS/RDATA Output
Receive digital output pin. In dual rail mode, this pin is the receive positive data output. In single rail mode, this pin is the receive non-return to zero (NRZ) data output.
Receive Loss of Signal
When a receive loss of signal occurs according to ITU-T G.775, the RLOS pin will go
"High" for a minimum of one RCLK cycle. RLOS will remain "High" until the loss of
signal condition clears. See the Receive Loss of Signal section of this datasheet for
more details.
NOTE: This pin can be used for redundancy applications to initiate an automatic
switch to a backup card.
Receive Clock Output
RCLK is the recovered clock from the incoming data stream. If the incoming signal
is absent or RTIP/RRING are in "High-Z", RCLK maintains its timing by using an
internal master clock as its reference. RPOS/RNEG data can be updated on either
edge of RCLK selected by RCLKE.
NOTE: RCLKE is a global setting that applies to all 8 channels.
5
XRT83VSH28
8-CHANNEL E1 SHORT-HAUL LINE INTERFACE UNIT
REV. 2.0.0
SIGNAL NAME
BGA
LEAD #
RTIP0
RTIP1
RTIP2
RTIP3
RTIP4
RTIP5
RTIP6
RTIP7
TYPE
DESCRIPTION
C1
G1
G18
C18
U1
L1
L18
T18
I
Receive Differential Tip Input
RTIP is the positive differential input from the line interface. Along with the RRING
signal, these pins should be coupled to a 1:1 transformer for proper operation.
RRING0
RRING1
RRING2
RRING3
RRING4
RRING5
RRING6
RRING7
D1
F1
F18
D18
T1
M1
M18
R18
I
Receive Differential Ring Input
RRING is the negative differential input from the line interface. Along with the RTIPsignal, these pins should be coupled to a 1:1 transformer for proper operation.
RXMUTE
T12
I
Receive Data Muting
Hardware Mode Only
This pin is AND-ed with each of the RLOS functions on a per channel basis. Therefore, if this pin is pulled "High" and a given channel experiences a loss of signal, then
the RPOS/RNEG output pins are automatically pulled "Low" to prevent data chattering. To disable this feature, the RxMUTE pin must be pulled "Low".
NOTE: This pin is internally pulled “High” with a 50k resistor
6
XRT83VSH28
8-CHANNEL E1 SHORT-HAUL LINE INTERFACE UNIT
SIGNAL NAME
BGA
LEAD #
RXRES1
RXRES0
R10
V10
REV. 2.0.0
TYPE
DESCRIPTION
I
Receive External Resistor Control Pins
Hardware mode Only
These pins are used in the Receive Internal Impedance mode for unique applications where an accurate resistor can be used to achieve optimal return loss. When
RxRES[1:0] are used, the LIU automatically sets the internal impedance to match
the line build out. For example: if 240 is selected, the LIU chooses an internal
impedance such that the parallel combination equals the impedance chosen by
TERSEL[1:0].
"00" = No External Fixed Resistor
"01" = 320
"10" = 280
"11" = 190
NOTE: These pins are internally pulled “Low” with a 50k resistor. This feature is
available in Host mode by programming the appropriate channel register.
RCLKE/
µPTS1
J16
I
Receive Clock Edge
Hardware Mode
This pin is used to select which edge of the recovered clock is used to update data to
the receiver on the RPOS/RNEG outputs. By default, data is updated on the risinge
edge. To udpdate data on the falling edge, this pin must be pulled "High".
Host Mode
PTS[2:1] pins are used to select the type of microprocessor to be used for Host
communication.
"00" = 8051 Intel Asynchronous
"01" = 68K Motorola Asynchronous
"10" = Power PC 403
"11" = MPC8xx Power PC Synchronous
NOTE: This pin is internally pulled “Low” with a 50k resistor.
7
XRT83VSH28
8-CHANNEL E1 SHORT-HAUL LINE INTERFACE UNIT
REV. 2.0.0
TRANSMIT SECTION
SIGNAL NAME
BGA
LEAD #
TYPE
DESCRIPTION
TCLKE/µPTS2
L15
I
Transmit Clock Edge
Hardware Mode
This pin is used to select which edge of the transmit clock is used to sample data
on the transmitter on the TPOS/TNEG inputs. By default, data is sampled on the
falling edge. To sample data on the rising edge, this pin must be pulled "High".
Host Mode
PTS[2:1] pins are used to select the type of microprocessor to be used for Host
communication.
"00" = 8051 Intel Asynchronous
"01" = 68K Motorola Asynchronous
"10" = Power PC 403
"11" = MPC8xx Power PC Synchronous
NOTE: This pin is internally pulled “Low” with a 50k resistor.
TTIP0
TTIP1
TTIP2
TTIP3
TTIP4
TTIP5
TTIP6
TTIP7
E3
G4
F17
C16
R2
N2
N16
P16
O
Transmit Differential Tip Output
TTIP is the positive differential output to the line interface. Along with the TRING
signal, these pins should be coupled to a 1:2 step up transformer for proper operation.
TRING0
TRING1
TRING2
TRING3
TRING4
TRING5
TRING6
TRING7
E2
F3
F15
E16
P2
N4
R15
P17
O
Transmit Differential Ring Output
TRING is the negative differential output to the line interface. Along with the TTIP
signal, these pins should be coupled to a 1:2 step up transformer for proper operation.
TPOS0
TPOS1
TPOS2
TPOS3
TPOS4
TPOS5
TPOS6
TPOS7
C5
A4
B14
D14
V4
U5
V15
T14
I
TPOS/TDATA Input
Transmit digital input pin. In dual rail mode, this pin is the transmit positive data
input. In single rail mode, this pin is the transmit non-return to zero (NRZ) data
input.
TNEG0
TNEG1
TNEG2
TNEG3
TNEG4
TNEG5
TNEG6
TNEG7
C4
B5
D13
B15
U4
V5
U14
R14
I
NOTE: Internally pulled "Low" with a 50K resistor.
Transmitter Negative NRZ Data Input
In dual rail mode, this signal is the negative-rail input data for the transmitter. In
single rail mode, this pin can be left unconnected while in Host mode. However, in
Hardware mode, this pin is used to select the type of encoding/decoding for the E1
data format. Connecting this pin “Low” enables HDB3. Connecting this pin “High”
selects AMI data format.
NOTE: Internally pulled “Low” with a 50k resistor.
8
XRT83VSH28
8-CHANNEL E1 SHORT-HAUL LINE INTERFACE UNIT
SIGNAL NAME
BGA
LEAD #
TCLK0
TCLK1
TCLK2
TCLK3
TCLK4
TCLK5
TCLK6
TCLK7
REV. 2.0.0
TYPE
DESCRIPTION
B4
A3
A15
C14
T3
T5
V16
U15
I
Transmit Clock Input
TCLK is the input facility clock used to sample the incoming TPOS/TNEG data. If
TCLK is absent, pulled "Low", or pulled "High", the transmitter outputs at TTIP/
TRING sends an all zero signal to the line. TPOS/TNEG data can be sampled on
either edge of TCLK selected by TCLKE.
TAOS0
TAOS1
TAOS2
TAOS3
TAOS4
TAOS5
TAOS6
TAOS7
D6
B6
A5
C6
T6
U6
V6
R6
I
TXON0
TXON1
TXON2
TXON3
TXON4
TXON5
TXON6
TXON7
A13
D12
C12
B12
V13
U13
R12
R13
I
NOTE: TCLKE is a global setting that applies to all 8 channels. These pins are
Internally pulled “Low” with 50k resistors.
Transmit All Ones for Channel
Hardware Mode Only
Setting this pin “High” enables the transmission of an all ones pattern to the line
from TTIP/TRING. If this pin is pulled “Low”, the transmitters operate in normal
throughput mode.
NOTE: Internally pulled “Low” with a 50k resistor for all channels. This feature is
available in Host mode by programming the appropriate channel register.
Transmit On/Off Input
Upon power up, the transmitters are powered off. Turning the transmitters On or
Off is selected through the microprocessor interface by programming the appropriate channel register while in Host mode. However, if TxONCNTL is set "High" in
the appropriate global register or if in Hardware mode, the activity of the transmitter
outputs is controlled by the TxON pins.
NOTE:
TxON is ideal for redundancy applications. See the Redundancy
Applications Section of this datasheet for more details. Internally pulled
"Low" with a 50K resistor.
9
XRT83VSH28
8-CHANNEL E1 SHORT-HAUL LINE INTERFACE UNIT
REV. 2.0.0
PARALLEL MICROPROCESSOR INTERFACE
SIGNAL NAME
BGA
LEAD
#
TYPE
DESCRIPTION
HW/HOST
T10
I
Mode Control Input
This pin is used to select Host mode or Hardware mode. By default, the LIU is set in
Hardware mode. To use Host mode, this pin must be pulled "Low".
NOTE: Internally pulled “High” with a 50k resistor.
WR_R/W/EQC0
D7
I
Write Input(R/W)/Equalizer Control Signal 0
Host Mode
This pin is used to communicate a Read or Write operation according to the which
microprocessor is chosen. See the Microprocessor Section of this datasheet for
details.
Hardware Mode
EQC[4:0] are used to set the Receiver Gain, Receiver Impedance and the Transmit
Line Build Out. See Table 23 for more details.
NOTE: Internally pulled “Low” with a 50k resistor.
RD_DS/EQC1
C7
I
Read Input (Data Strobe)/Equalizer Control Signal 1
Host Mode
This pin is used to communicate a Read or Write operation according to the which
microprocessor is chosen. See the Microprocessor Section of this datasheet for
details.
Hardware Mode
EQC[4:0] are used to set the Receiver Gain, Receiver Impedance and the Transmit
Line Build Out. See Table 23 for more details.
NOTE: Internally pulled “Low” with a 50k resistor.
ALE/EQC2
A7
I
Address Latch Input (Address Strobe)
Host Mode
This pin is used to latch the address contents into the internal registers within the LIU
device. See the Microprocessor Section of this datasheet for details.
Hardware Mode
EQC[4:0] are used to set the Receiver Gain, Receiver Impedance and the Transmit
Line Build Out. See Table 23 for more details.
NOTE: Internally pulled “Low” with a 50k resistor.
CS/EQC3
B7
I
Chip Select Input - Host mode:
Host Mode
This pin is used to initiate communication with the microprocessor interface. See the
Microprocessor Section of this datasheet for details.
Hardware Mode
EQC[4:0] are used to set the Receiver Gain, Receiver Impedance and the Transmit
Line Build Out. See Table 23 for more details.
NOTE: Internally pulled “Low” with a 50k resistor.
10
XRT83VSH28
8-CHANNEL E1 SHORT-HAUL LINE INTERFACE UNIT
REV. 2.0.0
SIGNAL NAME
BGA
LEAD
#
TYPE
DESCRIPTION
RDY/EQC4
A6
I/O
Ready Output (Data Transfer Acknowledge)
Host Mode (Parallel Microprocessor)
If Pin SER_PAR is pulled "Low", this output pin from the microprocessor block is used
to inform the local P that the Read or Write operation has been completed and is
waiting for the next command. See the Microprocessor Section of this datasheet for
details.
Host Mode (Serial Interface)
If Pin SER_PAR is pulled "High", this output pin from the serial interface is used to
read back the regsiter contents. See the Microprocessor Section of this datasheet for
details.
Hardware Mode
EQC[4:0] are used to set the Receiver Gain, Receiver Impedance and the Transmit
Line Build Out. See Table 23 for more details.
NOTE: Internally pulled “Low” with a 50k resistor.
D[7]/Loop14
D[6]/Loop04
D[5]/Loop15
D[4]/Loop05
D[3]/Loop16
D[2]/Loop06
D[1]/Loop17
D[0]/Loop07
T7
U7
V7
V8
V9
U8
U9
R7
I/O
Bi-Directional Data Bust/Loopback Mode Select
Host Mode
These pins are used for the 8-bit bi-directional data bus to allow data transfer to and
from the microprocessor interface.
Hardware Mode (Channels 4 through 7)
These pins are used to select the loopback mode. Each channel has two loopback
pins Loop[1:0].
"00" = No Loopback
"01" = Analog Local Loopback
"10" = Remote Loopback
"11" = Digital Loopback
NOTE: Internally pulled “Low” with a 50k resistor.
A[7]/Loop13
A[6]/Loop03
A[5]/Loop12
A[4]/Loop02
A[3]/Loop11
A[2]/Loop01
A[1]/Loop10
A[0]/Loop00
A12
B11
C11
D11
A11
B10
A10
C10
I
Direct Address Bus/Loopback Mode Select
Host Mode
These pins are used for the 8-bit direct address bus to allow access to the internal
registers within the microprocessor interface.
Hardware Mode (Channels 0 through 3)
These pins are used to select the loopback mode. Each channel has two loopback
pins Loop[1:0].
"00" = No Loopback
"01" = Analog Local Loopback
"10" = Remote Loopback
"11" = Digital Loopback
NOTE: Internally pulled “Low” with a 50k resistor.
11
XRT83VSH28
8-CHANNEL E1 SHORT-HAUL LINE INTERFACE UNIT
REV. 2.0.0
SIGNAL NAME
BGA
LEAD
#
TYPE
DESCRIPTION
µPCLK/ATAOS
T13
I
Synchronous Microprocessor Clock/Automatic Transmit All Ones
Host Mode
This synchronous input clock is used as the internal master clock to the microprocessor interface when configured for in a synchronous mode.
Hardware Mode
This pin is used select an all ones signal to the line interface through TTIP/TRING any
time that a loss of signal occurs. This feature is avaiable in Host mode by programming the appropriate global register.
NOTE: Internally pulled “Low” with a 50k resistor.
INT
L16
O
Interrupt Output
Host Mode
This signal is asserted "Low" when a change in alarm status occurs. Once the status
registers have been read, the interrupt pin will return "High". GIE (Global Interrupt
Enable) must be set "High" in the appropriate global register to enable interrupt generation.
NOTE:
This pin is an open-drain output that requires an external 10K pull-up
resistor.
JITTER ATTENUATOR
SIGNAL
NAME
BGA
LEAD #
JASEL0
JASEL1
A14
B13
TYPE
DESCRIPTION
I
Jitter Attenuator Select Pins Hardware Mode
JASEL[1:0] pins are used to place the jitter attenuator in the transmit path, the receive
path or to disable it.
JA BW Hz
E1
JASEL1
JASEL0
JA Path
FIFO Size
0
0
Disabled
-----
--------
0
1
Transmit
10
32/32
1
0
Receive
10
32/32
1
1
Receive
1.5
64/64
NOTE: These pins are internally pulled “Low” with 50k resistors.
12
XRT83VSH28
8-CHANNEL E1 SHORT-HAUL LINE INTERFACE UNIT
REV. 2.0.0
CLOCK SYNTHESIZER
SIGNAL NAME
BGA
LEAD #
TYPE
MCLKOUT
H1
O
Synthesized Master Clock Output
This signal is the output of the Master Clock Synthesizer PLL which is at E1 rate.
MCLKE1
J1
I
E1 Master Clock Input
A 2.048MHz clock for with an accuracy of better than ±50ppm and a duty cycle of
40% to 60% can be provided at this pin.
DESCRIPTION
NOTE: This pin is internally pulled “Low” with a 50k resistor.
13
XRT83VSH28
8-CHANNEL E1 SHORT-HAUL LINE INTERFACE UNIT
REV. 2.0.0
ALARM FUNCTIONS/REDUNDANCY SUPPORT
SIGNAL NAME
BGA
LEAD #
TYPE
DESCRIPTION
GAUGE
J18
I
Twisted Pair Cable Wire Gauge Select
Hardware Mode Only
This pin is used to match the frequency characteristics according to the gauge of
wire used in Telecom circuits. By default, the LIU is matched to 22 gauge or 24
gauge wire. To select 26 gauge, this pin must be pulled "High".
NOTE: Internally pulled “Low” with a 50k resistor.
DMO0
DMO1
DMO2
DMO3
DMO4
DMO5
DMO6
DMO7
D5
D4
C15
C13
R5
P4
U17
V14
O
RESET
T8
I
Digital Monitor Output
When no transmit output pulse is detected for more than 128 TCLK cycles within the
transmit output buffer, the DMO pin will go "High" for a minimum of one TCLK cycle.
DMO will remain "High" until the transmitter sends a valid pulse.
NOTE: This pin can be used for redundancy applications to initiate an automatic
switch to a backup card.
Hardware Reset Input
Active low signal. When this pin is pulled "Low" for more than 10µS, the internal registers are set to their default state. See the register description for the default values.
NOTE: Internally pulled "High" with a 50K resistor.
SR/DR
K4
I
Single-Rail/Dual-Rail Data Format
Hardware Mode Only
This pin is used to control the data format on the facility side of the LIU to interface to
a Framer or Mapper/ASIC device. By default, dual rail mode is selected which relies
upon the Framer to handle the encoding/decoding functions. To select single rail
mode, this pin must be pulled "High". If single rail mode is selected, the LIU can
encode/decode AMI or HDB3 data formats.
NOTE: Internally pulled “Low” with a 50k resistor.
RXTSEL
U11
I
Receiver Termination Select
Hardware Mode
This pin is used to select between the internal and external impedance modes for
the receive path. By default, the receivers are configured for external impedance
mode, which is ideal for redundancy applications without relays. To select internal
impedance, this pin must be pulled "HIgh".
Host Mode
Internal/External impedance can be selected by programming the appropriate channel registers. However, to assist in redundancy applications, this pin can be used for
a hard switch if the RxTCNTL bit is set "High" in the appropriate global register. If
RxTCNTL is set "High", the individual RxTSEL register bits are ignored.
NOTE: This pin is internally pulled “Low” with a 50k resistor.
TXTSEL
V11
I
Transmitter Termination Select
Hardware Mode
This pin is used to select between the internal and external impedance modes for
the transmit path. By default, the receivers are configured for external impedance
mode, which is ideal for redundancy applications without relays. To select internal
impedance, this pin must be pulled "HIgh".
NOTE: This pin is internally pulled "Low".
14
XRT83VSH28
8-CHANNEL E1 SHORT-HAUL LINE INTERFACE UNIT
REV. 2.0.0
SIGNAL NAME
BGA
LEAD #
TYPE
DESCRIPTION
TERSEL
R11
I
Termination Impedance Select
Hardware Mode Only
The TERSEL pin is used to select the transmitter and receiver impedance. By
default, the impedance is set to 75.
"Low" = 75
"High" = 120
NOTE: This pin is internally pulled "Low" with a 50k resistor.
TEST
U12
I
Factory Test Mode
For normal operation, the TEST pin should be tied to ground.
NOTE: Internally pulled "Low" with a 50k resistor.
ICT
V12
I
In Circuit Testing
When this pin is tied "Low", all output pins are forced to "High" impedance for in circuit testing.
NOTE: Internally pulled "High" with a 50K resistor.
15
XRT83VSH28
8-CHANNEL E1 SHORT-HAUL LINE INTERFACE UNIT
REV. 2.0.0
SERIAL MICROPROCESSOR INTERFACE
SIGNAL NAME
BGA
LEAD #
TYPE
DESCRIPTION
SER_PAR
P18
I
Serial/Parallel Select Input (Host Mode Only)
This pin is used in the Host mode to select between the parallel microprocessor
or serial interface. By default, the Host mode operates in the parallel microprocessor mode. To configure the device for a serial interface, this pin must be
pulled "HIgh".
NOTE: Internally pulled “Low” with a 50k resistor.
SCLK
T13
I
Serial Clock Input (Host Mode Only)
If Pin SER_PAR is pulled "High", this input pin is used as the timing reference
for the serial microprocessor interface. See the Microprocessor Section of this
datasheet for details.
SDI
C10
I
Serial Data Input (Host Mode Only)
If Pin SER_PAR is pulled "High", this input pin from the serial interface is used
to input the serial data for Read and Write operations. See the Microprocessor
Section of this datasheet for details.
SDO
R7
O
Serial Data Output (Host Mode Only)
If Pin SER_PAR is pulled "High", this output pin from the serial interface is used
to read back the regsiter contents. See the Microprocessor Section of this
datasheet for details.
JTAGtip
JTAGring
E18
B18
Analog JTAG Positive Pin
Analog JTAG Negative Pin
TDO
B1
Test Data Out
This pin is used as the output data pin for the boundary scan chain.
TDI
R1
Test Data In
This pin is used as the input data pin for the boundary scan chain.
TCK
N1
Test Clock Input
This pin is used as the input clock source for the boundary scan chain.
TMS
E1
Test Mode Select
This pin is used as the input mode select for the boundary scan chain.
SENSE
N18
****
Factory Test Pin
POWER AND GROUND
SIGNAL NAME
TGND
BGA
LEAD #
D3
F2
E15
C17
R3
P3
T16
R16
TYPE
****
DESCRIPTION
Transmitter Analog Ground
It’s recommended that all ground pins of this device be tied together.
16
XRT83VSH28
8-CHANNEL E1 SHORT-HAUL LINE INTERFACE UNIT
SIGNAL NAME
BGA
LEAD #
REV. 2.0.0
TYPE
DESCRIPTION
TVDD
E4
F4
F16
E17
R4
P1
N15
P15
****
Transmit Analog Power Supply (3.3V ±5%)
TVDD can be shared with DVDD. However, it is recommended that TVDD be
isolated from the analog power supply RVDD. For best results, use an internal
power plane for isolation. If an internal power plane is not available, a ferrite
bead can be used. Each power supply pin should be bypassed to ground
through an external 0.1F capacitor.
RVDD
C2
E5
G16
D16
V2
N3
N17
U18
****
Receive Analog Power Supply (3.3V ±5%)
RVDD should not be shared with other power supplies. It is recommended that
RVDD be isolated from the digital power supply DVDD and the analog power
supply TVDD. For best results, use an internal power plane for isolation. If an
internal power plane is not available, a ferrite bead can be used. Each power
supply pin should be bypassed to ground through an external 0.1F capacitor.
RGND
D2
G3
G17
D17
T2
M2
M17
R17
****
Receiver Analog Ground
It’s recommended that all ground pins of this device be tied together.
AVDD-Bias
K17
J3
J2
****
Analog Power Supply (1.8V ±5%)
AVDD should be isolated from the digital power supplies. For best results, use
an internal power plane for isolation. If an internal power plane is not available,
a ferrite bead can be used. Each power supply pin should be bypassed to
ground through at least one 0.1F capacitor.
AGND
J17
K3
L4
****
Analog Ground
It’s recommended that all ground pins of this device be tied together.
DVDD3v3
A18
R9
D9
K15
J4
****
Digital Power Supply (3.3V ±5%)
DVDD should be isolated from the analog power supplies. For best results, use
an internal power plane for isolation. If an internal power plane is not available,
a ferrite bead can be used. Every two DVDD power supply pins should be
bypassed to ground through at least one 0.1F capacitor.
DVDD1v8
V1
U10
K18
D10
A9
****
Digital Power Supply (1.8V ±5%)
DVDD should be isolated from the analog power supplies. For best results, use
an internal power plane for isolation. If an internal power plane is not available,
a ferrite bead can be used. Every two DVDD power supply pins should be
bypassed to ground through at least one 0.1F capacitor.
NOTE: For proper operation, the power-up sequence is: bring up 1.8V power
befor the 3.3V.
17
XRT83VSH28
8-CHANNEL E1 SHORT-HAUL LINE INTERFACE UNIT
REV. 2.0.0
SIGNAL NAME
BGA
LEAD #
TYPE
DGND
A1
R8
T9
H17
B9
D8
C9
G15
K2
V18
****
NC
A8, B8,
C8, K1,
T11
I
DESCRIPTION
Digital Ground
It’s recommended that all ground pins of this device be tied together.
No Connect PIns
18
XRT83VSH28
8-CHANNEL E1 SHORT-HAUL LINE INTERFACE UNIT
REV. 2.0.0
FUNCTIONAL DESCRIPTION
The XRT83VSH28 is a fully integrated 8-channel short-haul line interface unit (LIU) that operates from a 1.8V
and a 3.3V power supply. The LIU features are programmed through a standard microprocessor interface or
controlled through Hardware mode. EXAR’s LIU has patented high impedance circuits that allow the
transmitter outputs and receiver inputs to be high impedance when experiencing a power failure or when the
LIU is powered off. Key design features within the LIU optimize 1:1 or 1+1 redundancy and non-intrusive
monitoring applications to ensure reliability without using relays. Additional features include RLOS, a 16-bit
LCV counter for each channel, AIS, QRSS generation/detection, Network Loop Code generation/detection,
TAOS, DMO, and diagnostic loopback modes.
1.0 HARDWARE MODE VS HOST MODE
The LIU supports a parallel or serial microprocessor interface (Host mode) for programming the internal
features, or a Hardware mode that can be used to configure the device.
1.1
Feature Differences in Hardware Mode
Some features within the Hardware mode are not supported on a per channel basis. The differences between
Hardware mode and Host mode are descibed below in Table 1.
TABLE 1: DIFFERENCES BETWEEN HARDWARE MODE AND HOST MODE
FEATURE
HOST MODE
HARDWARE MODE
Tx Test Patterns
Fully Supported
RxRES[1:0]
Per Channel
In Hardware mode, RxRES[1:0] is a global setting that applies to
all channels.
TERSEL
Per Channel
In Hardware mode, TERSEL is a global setting that applies to all
channels.
EQC[4:0]
Per Channel
In Hardware mode, the EQC[4:0] is a global setting that applies to
all channels.
Dual Loopback
Fully Supported
JASEL[1:0]
Per Channel
In Hardware mode, the jitter attenuator selection is a global setting
that applies to all channels.
RxTSEL
Per Channel
In Hardware mode, the receive termination select is a global setting that applies to all channels.
TxTSEL
Per Channel
In Hardware mode, the transmit termination select is a global setting that applies to all channels.
QRSS diagnostic patterns are not available in Hardware mode.
The TAOS feature is available.
In Hardware mode, dual loopback mode is not supported.
Remote, Analog local, and digital loopback modes are available.
19
XRT83VSH28
8-CHANNEL E1 SHORT-HAUL LINE INTERFACE UNIT
REV. 2.0.0
2.0 RECEIVE PATH LINE INTERFACE
The receive path of the XRT83VSH28 LIU consists of 8 independent E1 receivers. The following section
describes the complete receive path from RTIP/RRING inputs to RCLK/RPOS/RNEG outputs. A simplified
block diagram of the receive path is shown in Figure 3.
FIGURE 3. SIMPLIFIED BLOCK DIAGRAM OF THE RECEIVE PATH
RCLK
RPOS
RNEG
2.1
2.1.1
HDB3 Decoder
Rx Jitter
Attenuator
Clock & Data
Recovery
Peak Detector
& Slicer
RTIP
RRING
Line Termination (RTIP/RRING)
CASE 1: Internal Termination
The input stage of the receive path accepts standard E1 twisted pair or E1 coaxial cable inputs through RTIP
and RRING. The physical interface is optimized by placing the terminating impedance inside the LIU. This
allows one bill of materials for all modes of operation reducing the number of external components necessary
in system design. The receive termination impedance is selected by programming TERSEL to match the line
impedance. Selecting the internal impedance is shown in Table 2.
TABLE 2: SELECTING THE INTERNAL IMPEDANCE
TERSEL
RECEIVE TERMINATION
0h
75
1h
120
The XRT83VSH28 has the ability to switch the internal termination to "High" impedance by programming
RxTSEL in the appropriate channel register. For internal termination, set RxTSEL to "1". By default, RxTSEL
is set to "0" ("High" impedance). For redundancy applications, a dedicated hardware pin (RxTSEL) is also
available to control the receive termination for all channels simultaneously. This hardware pin takes priority
over the register setting if RxTCNTL is set to "1" in the appropriate global register. If RxTCNTL is set to "0", the
state of this pin is ignored. See Figure 4 for a typical connection diagram using the internal termination.
FIGURE 4. TYPICAL CONNECTION DIAGRAM USING INTERNAL TERMINATION
XRT83VSH28 LIU
Receiver
Input
RTIP
1:1
Line Interface E1
RRING
One Bill of Materials
Internal Impedance
20
XRT83VSH28
8-CHANNEL E1 SHORT-HAUL LINE INTERFACE UNIT
2.1.2
REV. 2.0.0
CASE 2: Internal Termination With One External Fixed Resistor for All Modes
Along with the internal termination, a high precision external fixed resistor can be used to optimize the return
loss. This external resistor can be used for all modes of operation ensuring one bill of materials. There are
three resistor values that can be used by setting the RxRES[1:0] bits in the appropriate channel register.
Selecting the value for the external fixed resistor is shown in Table 3.
TABLE 3: SELECTING THE VALUE OF THE EXTERNAL FIXED RESISTOR
RXRES[1:0]
EXTERNAL FIXED RESISTOR
0h (00)
None
1h (01)
320
2h (10)
280
3h (11)
190
By default, RxRES[1:0] is set to "None" for no external fixed resistor. If an external fixed resistor is used, the
XRT83VSH28 uses the parallel combination of the external fixed resistor and the internal termination as the
input impedance. See Figure 5 for a typical connection diagram using the external fixed resistor.
NOTE: Without the external resistor, the XRT83VSH28 meets all return loss specifications. This mode was created to add
flexibility for optimizing return loss by using a high precision external resistor.
FIGURE 5. TYPICAL CONNECTION DIAGRAM USING ONE EXTERNAL FIXED RESISTOR
XRT83VSH28 LIU
Receiver
Input
RTIP
RRING
1:1
R
R=320, 280, or 190
Internal Impedance
21
Line Interface E1
XRT83VSH28
8-CHANNEL E1 SHORT-HAUL LINE INTERFACE UNIT
REV. 2.0.0
2.2
Clock and Data Recovery
The receive clock (RCLK) is recovered by the clock and data recovery circuitry. An internal PLL locks on the
incoming data stream and outputs a clock that’s in phase with the incoming signal. This allows for multichannels to arrive from different timing sources and remain independent. In the absence of an incoming
signal, RCLK maintains its timing by using the internal master clock as its reference. The recovered data can
be updated on either edge of RCLK. By default, data is updated on the rising edge of RCLK. To update data
on the falling edge of RCLK, set RCLKE to "1" in the appropriate global register. Figure 6 is a timing diagram
of the receive data updated on the rising edge of RCLK. Figure 7 is a timing diagram of the receive data
updated on the falling edge of RCLK. The timing specifications are shown in Table 4.
FIGURE 6. RECEIVE DATA UPDATED ON THE RISING EDGE OF RCLK
RC LKR
R DY
RC LKF
RC LK
RPOS
or
RNEG
R OH
FIGURE 7. RECEIVE DATA UPDATED ON THE FALLING EDGE OF RCLK
RCLKF
RDY
RCLKR
RCLK
RPOS
or
RNEG
ROH
TABLE 4: TIMING SPECIFICATIONS FOR RCLK/RPOS/RNEG
PARAMETER
SYMBOL
MIN
TYP
MAX
UNITS
RCLK Duty Cycle
RCDU
45
50
55
%
Receive Data Setup Time
RSU
150
-
-
ns
Receive Data Hold Time
RHO
150
-
-
ns
RCLK to Data Delay
RDY
-
-
40
ns
RCLK Rise Time (10% to 90%)
with 25pF Loading
RCLKR
-
-
40
ns
RCLK Fall Time (90% to 10%)
with 25pF Loading
RCLKF
-
-
40
ns
NOTE: VDD=3.3V ±5%, TA=25°C, Unless Otherwise Specified
22
XRT83VSH28
8-CHANNEL E1 SHORT-HAUL LINE INTERFACE UNIT
2.2.1
REV. 2.0.0
Receive Sensitivity
To meet short haul requirements, the XRT83VSH28 can accept E1 signals that have been attenuated by 12dB
of flat loss. However, the XRT83VSH28 can tolerate cable loss and flat loss beyond the industry specifications.
The receive sensitivity in the short haul mode is approximately 1,800 feet without experiencing bit errors, LOF,
pattern synchronization, etc. Although data integrity is maintained, the RLOS function (if enabled) will report an
RLOS condition according to the receiver loss of signal section in this datasheet. The test configuration for
measuring the receive sensitivity is shown in Figure 8.
FIGURE 8. TEST CONFIGURATION FOR MEASURING RECEIVE SENSITIVITY
W&G ANT20
Tx
Cable Loss
Network
Analyzer
Flat Loss
Rx
Rx
Tx
External Loopback
XRT83VSH28
8-Channel
Short Haul LIU
E1 = PRBS 215 - 1
2.2.2
Interference Margin
The interference margin for the XRT83VSH28 is -15db. The test configuration for measuring the interference
margin is shown in Figure 9.
FIGURE 9. TEST CONFIGURATION FOR MEASURING INTERFERENCE MARGIN
E1 = 1,024kHz
Sinewave
Generator
Flat Loss
E1 = PRBS 215 - 1
W&G ANT20
Network
Analyzer
Rx
Tx
Rx
2.2.3
External Loopback
Cable Loss
Tx
XRT83VSH28
8-Channel LIU
General Alarm Detection and Interrupt Generation
The receive path detects RLOS, AIS, QRPD and FLS. These alarms can be individually masked to prevent the
alarm from triggering an interrupt. To enable interrupt generation, the Global Interrupt Enable (GIE) bit must be
set "High" in the appropriate global register. Any time a change in status occurs (it the alarms are enabled), the
interrupt pin will pull "Low" to indicate an alarm has occurred. Once the status registers have been read, the
INT pin will return "High". The status registers are Reset Upon Read (RUR). The interrupts are categorized in
a hierarchical process block. Figure is a simplified block diagram of the interrupt generation process.
NOTE: The interrupt pin is an open-drain output that requires a 10k external pull-up resistor.
23
XRT83VSH28
8-CHANNEL E1 SHORT-HAUL LINE INTERFACE UNIT
REV. 2.0.0
2.2.3.1
RLOS (Receiver Loss of Signal)
The XRT83VSH28 supports both G.775 or ETSI-300-233 RLOS detection scheme.
In G.775 mode, RLOS is declared when the received signal is less than 375mV for 32 consecutive pulse
periods (typical). The device clears RLOS when the receive signal achieves 12.5% ones density with no more
than 15 consecutive zeros in a 32 bit sliding window and the signal level exceeds 425mV (typical).
In ETSI-300-233 mode the device declares RLOS when the input level drops below 375mV (typical) for more
than 2048 pulse periods (1msec).
The device exits RLOS when the input signal exceeds 425mV (typical) and has transitions for more than 32
pulse periods with 12.5% ones density with no more than 15 consecutive zero’s in a 32 bit sliding window.
ETSI-300-233 RLOS detection method is only available in Host mode.
2.2.3.2
EXLOS (Extended Loss of Signal)
By enabling the extended loss of signal by programming the appropriate channel register, the digital RLOS is
extended to count 4,096 consecutive zeros before declaring RLOS. By default, EXLOS is disabled and RLOS
operates in normal mode.
2.2.3.3
AIS (Alarm Indication Signal)
The XRT83VSH28 adheres to the ITU-T G.775 specification for an all ones pattern. The AIS is set to "1" if the
incoming signal has 2 or less zeros in a 512-bit window. AIS will clear when the incoming signal has 3 or more
zeros in the 512-bit window.
2.2.3.4
FLSD (FIFO Limit Status Detection)
The purpose of the FIFO limit status is to indicate when the Read and Write FIFO pointers are within a predetermined range (over-flow or under-flow indication). The FLSD is set to "1" if the FIFO Read and Write
Pointers are within ±3-Bits.
2.2.3.5
LCVD (Line Code Violation Detection)
The LIU contains 8 independent, 16-bit LCV counters. When the counters reach full-scale, they remain
saturated at FFFFh until they are reset globally or on a per channel basis. For performance monitoring, the
counters can be updated globally or on a per channel basis to place the contents of the counters into holding
registers. The LIU uses an indirect address bus to access a counter for a given channel. Once the contents of
the counters have been placed in holding registers, they can be individually read out 8-bits at a time according
to the BYTEsel bit in the appropriate global register. By default, the LSB is placed in the holding register until
the BYTEsel is pulled "High" where upon the MSB will be placed in the holding register for read back. Once
both bytes have been read, the next channel may be selected for read back.
By default, the LVC/OFD will be set to a "1" if the receiver is currently detecting line code violations or
excessive zeros for HDB3. In AMI mode, the LCVD will be set to a "1" if the receiver is currently detecting
bipolar violations or excessive zeros. However, if the LIU is configured to monitor the 16-bit LCV counter by
programming the appropriate global register, the LCV/OFD will be set to a "1" if the counter saturates.
2.3
Receive Jitter Attenuator
The receive path has a dedicated jitter attenuator that reduces phase and frequency jitter in the recovered
clock. The jitter attenuator uses a data FIFO (First In First Out) with a programmable depth of 32-bit or 64-bit.
If the LIU is used for line synchronization (loop timing systems), the JA should be enabled. When the Read and
Write pointers of the FIFO are within 2-Bits of over-flowing or under-flowing, the bandwidth of the jitter
attenuator is widened to track the short term input jitter, thereby avoiding data corruption. When this condition
occurs, the jitter attenuator will not attenuate input jitter until the Read/Write pointer’s position is outside the 2Bit window. The bandwidth is programmable to either 10Hz or 1.5Hz (1.5Hz automatically selects the 64-Bit
FIFO depth). The JA has a clock delay equal to ½ of the FIFO bit depth.
NOTE: If the LIU is used in a multiplexer/mapper application where stuffing bits are typically removed, the transmit path has
a dedicated jitter attenuator to smooth out the gapped clock. See the Transmit Section of this datasheet.
24
XRT83VSH28
8-CHANNEL E1 SHORT-HAUL LINE INTERFACE UNIT
2.4
REV. 2.0.0
HDB3 Decoder
In single rail mode, RPOS can decode AMI or HDB3 signals. HDB3 is defined as any block of 4 successive
zeros replaced with 000V or B00V, so that two successive V pulses are of opposite polarity to prevent a DC
component. If the HDB3 decoder is selected, the receive path removes the V and B pulses so that the original
data is output to RPOS.
2.5
RPOS/RNEG/RCLK
The digital output data can be programmed to either single rail or dual rail formats. Figure 10 is a timing
diagram of a repeating "0011" pattern in single-rail mode. Figure 11 is a timing diagram of the same fixed
pattern in dual rail mode.
FIGURE 10. SINGLE RAIL MODE WITH A FIXED REPEATING "0011" PATTERN
0
0
1
1
0
RCLK
RPOS
FIGURE 11. DUAL RAIL MODE WITH A FIXED REPEATING "0011" PATTERN
0
0
1
RCLK
RPOS
RNEG
25
1
0
XRT83VSH28
8-CHANNEL E1 SHORT-HAUL LINE INTERFACE UNIT
REV. 2.0.0
2.6
RxMUTE (Receiver LOS with Data Muting)
The receive muting function can be selected by setting RxMUTE to "1" in the appropriate global register. If
selected, any channel that experiences an RLOS condition will automatically pull RPOS and RNEG "Low" to
prevent data chattering. If RLOS does not occur, the RxMUTE will remain inactive until an RLOS on a given
channel occurs. The default setting for RxMUTE is "0" which is disabled. A simplified block diagram of the
RxMUTE function is shown in Figure 12.
FIGURE 12. SIMPLIFIED BLOCK DIAGRAM OF THE RXMUTE FUNCTION
RPOS
RNEG
RxMUTE
RLOS
26
XRT83VSH28
8-CHANNEL E1 SHORT-HAUL LINE INTERFACE UNIT
REV. 2.0.0
3.0 TRANSMIT PATH LINE INTERFACE
The transmit path of the XRT83VSH28 LIU consists of 8 independent E1 transmitters. The following section
describes the complete transmit path from TCLK/TPOS/TNEG inputs to TTIP/TRING outputs. A simplified
block diagram of the transmit path is shown in Figure 13.
FIGURE 13. SIMPLIFIED BLOCK DIAGRAM OF THE TRANSMIT PATH
TCLK
TPOS
TNEG
3.1
HDB3 Encoder
Tx Jitter
Attenuator
Timing
Control
Tx Pulse Shaper
& Pattern Gen
TTIP
Line Driver
TRING
TCLK/TPOS/TNEG Digital Inputs
In dual rail mode, TPOS and TNEG are the digital inputs for the transmit path. In single rail mode, TNEG has
no function and can be left unconnected. The XRT83VSH28 can be programmed to sample the inputs on
either edge of TCLK. By default, data is sampled on the falling edge of TCLK. To sample data on the rising
edge of TCLK, set TCLKE to "1" in the appropriate global register. Figure 14 is a timing diagram of the
transmit input data sampled on the falling edge of TCLK. Figure 15 is a timing diagram of the transmit input
data sampled on the rising edge of TCLK. The timing specifications are shown in Table 5.
FIGURE 14. TRANSMIT DATA SAMPLED ON FALLING EDGE OF TCLK
TCLKR
TCLKF
TCLK
TPOS
or
TNEG
TSU
THO
FIGURE 15. TRANSMIT DATA SAMPLED ON RISING EDGE OF TCLK
TCLKF
TCLK
TPOS
or
TNEG
TSU
THO
27
TCLKR
XRT83VSH28
8-CHANNEL E1 SHORT-HAUL LINE INTERFACE UNIT
REV. 2.0.0
TABLE 5: TIMING SPECIFICATIONS FOR TCLK/TPOS/TNEG
PARAMETER
SYMBOL
MIN
TYP
MAX
UNITS
TCLK Duty Cycle
TCDU
30
50
70
%
Transmit Data Setup Time
TSU
50
-
-
ns
Transmit Data Hold Time
THO
30
-
-
ns
TCLK Rise Time (10% to 90%)
TCLKR
-
-
40
ns
TCLK Fall Time (90% to 10%)
TCLKF
-
-
40
ns
NOTE: VDD=3.3V ±5%, TA=25°C, Unless Otherwise Specified
3.2
HDB3 Encoder
In single rail mode, the LIU can encode the TPOS input signal to AMI or HDB3 data. With HDB3 encoding
selected, any sequence with four or more consecutive zeros in the input will be replaced with 000V or B00V,
where "B" indicates a pulse conforming to the bipolar rule and "V" representing a pulse violating the rule. An
example of HDB3 encoding is shown in Table 6.
TABLE 6: EXAMPLES OF HDB3 ENCODING
NUMBER OF PULSES BEFORE
NEXT 4 ZEROS
Input
0000
HDB3 (Case 1)
Odd
000V
HDB3 (Case 2)
Even
B00V
28
XRT83VSH28
8-CHANNEL E1 SHORT-HAUL LINE INTERFACE UNIT
3.3
REV. 2.0.0
Transmit Jitter Attenuator
The XRT83VSH28 LIU is ideal for multiplexer or mapper applications where the network data crosses multiple
timing domains. As the higher data rates are de-multiplexed down to E1 data, stuffing bits are typically
removed which can leave gaps in the incoming data stream. The transmit path has a dedicated jitter attenuator
with a 32-Bit or 64-Bit FIFO that is used to smooth the gapped clock into a steady E1 output. The maximum
gap width of the 8-channel LIU is shown in Table 7.
TABLE 7: MAXIMUM GAP WIDTH FOR MULTIPLEXER/MAPPER APPLICATIONS
FIFO DEPTH
MAXIMUM GAP WIDTH
32-Bit
20 UI
64-Bit
50 UI
NOTE: If the LIU is used in a loop timing system, the receive path has a dedicated jitter attenuator. See the Receive
Section of this datasheet.
3.4
TAOS (Transmit All Ones)
The XRT83VSH28 has the ability to transmit all ones on a per channel basis by programming the appropriate
channel register. This function takes priority over the digital data present on the TPOS/TNEG inputs. For
example: If a fixed "0011" pattern is present on TPOS in single rail mode and TAOS is enabled, the transmitter
will output all ones. In addition, if digital or dual loopback is selected, the data on the RPOS output will be
equal to the data on the TPOS input. Figure 16 is a diagram showing the all ones signal at TTIP and TRING.
FIGURE 16. TAOS (TRANSMIT ALL ONES)
1
1
1
TAOS
3.5
Transmit Diagnostic Features
In addition to TAOS, the XRT83VSH28 offers diagnostic features for analyzing network integrity such as
ATAOS and QRSS on a per channel basis by programming the appropriate registers. These diagnostic
features take priority over the digital data present on TPOS/TNEG inputs. The transmitters will send the
diagnostic code to the line and will be maintained in the digital loopback if selected. When the LIU is
responsible for sending diagnostic patterns, the LIU is automatically placed in the single rail mode.
3.5.1
ATAOS (Automatic Transmit All Ones)
If ATAOS is selected by programming the appropriate global register, an AMI all ones signal will be transmitted
for each channel that experiences an RLOS condition. If RLOS does not occur, the ATAOS will remain inactive
until an RLOS on a given channel occurs. A simplified block diagram of the ATAOS function is shown in
Figure 17.
29
XRT83VSH28
8-CHANNEL E1 SHORT-HAUL LINE INTERFACE UNIT
REV. 2.0.0
FIGURE 17. SIMPLIFIED BLOCK DIAGRAM OF THE ATAOS FUNCTION
TTIP
Tx
TRING
TAOS
ATAOS
RLOS
3.5.2
QRSS Generation
The XRT83VSH28 can transmit a QRSS random sequence to a remote location from TTIP/TRING. The
polynomial is shown in Table 8.
TABLE 8: RANDOM BIT SEQUENCE POLYNOMIALS
RANDOM PATTERN
E1
QRSS
215 - 1
30
XRT83VSH28
8-CHANNEL E1 SHORT-HAUL LINE INTERFACE UNIT
3.6
REV. 2.0.0
DMO (Digital Monitor Output)
The driver monitor circuit is used to detect transmit driver failures by monitoring the activities at TTIP/TRING
outputs. Driver failure may be caused by a short circuit in the primary transformer or system problems at the
transmit inputs. If the transmitter of a channel has no output for more than 128 clock cycles, DMO goes "High"
until a valid transmit pulse is detected. If the DMO interrupt is enabled, the change in status of DMO will cause
the interrupt pin to go "Low". Once the status register is read, the interrupt pin will return "High" and the status
register will be reset (RUR).
3.7
Line Termination (TTIP/TRING)
The output stage of the transmit path generates standard return-to-zero (RZ) signals to the line interface for E1
twisted pair or E1 coaxial cable. The physical interface is optimized by placing the terminating impedance
inside the LIU. This allows one bill of materials for all modes of operation reducing the number of external
components necessary in system design. The transmitter outputs only require one DC blocking capacitor of
0.68F. For redundancy applications (or simply to tri-state the transmitters), set TxTSEL to a "1" in the
appropriate channel register. A typical transmit interface is shown in Figure 18.
FIGURE 18. TYPICAL CONNECTION DIAGRAM USING INTERNAL TERMINATION
XRT83VSH28 LIU
TTIP
Transmitter
Output
1:2
C=0.68uF
Line Interface E1
TRING
One Bill of Materials
Internal Impedance
31
XRT83VSH28
8-CHANNEL E1 SHORT-HAUL LINE INTERFACE UNIT
REV. 2.0.0
4.0 E1 APPLICATIONS
This applications section describes common E1 system considerations along with references to application
notes available for reference where applicable.
4.1
Loopback Diagnostics
The XRT83VSH28 supports several loopback modes for diagnostic testing. The following section describes
the local analog loopback, remote loopback, digital loopback, and dual loopback modes.
4.1.1
Local Analog Loopback
With local analog loopback activated, the transmit output data at TTIP/TRING is internally looped back to the
analog inputs at RTIP/RRING. External inputs at RTIP/RRING are ignored while valid transmit output data
continues to be sent to the line. A simplified block diagram of local analog loopback is shown in Figure 19.
FIGURE 19. SIMPLIFIED BLOCK DIAGRAM OF LOCAL ANALOG LOOPBACK
QRSS
TAOS
TCLK
TPOS
TNEG
Encoder
JA
Timing
Control
RCLK
RPOS
RNEG
Decoder
JA
Data and
Clock
Recovery
TTIP
TRING
Tx
RTIP
RRING
Rx
NOTE: The transmit diagnostic features such as TAOS and QRSS take priority over the transmit input data at TCLK/TPOS/
TNEG.
4.1.2
Remote Loopback
With remote loopback activated, the receive input data at RTIP/RRING is internally looped back to the transmit
output data at TTIP/TRING. The remote loopback includes the Receive JA (if enabled). The transmit input
data at TCLK/TPOS/TNEG are ignored while valid receive output data continues to be sent to the system. A
simplified block diagram of remote loopback is shown in Figure 20.
FIGURE 20. SIMPLIFIED BLOCK DIAGRAM OF REMOTE LOOPBACK
QRSS
TAOS
TCLK
TPOS
TNEG
Encoder
JA
Timing
Control
RCLK
RPOS
RNEG
Decoder
JA
Data and
Clock
Recovery
32
TTIP
TRING
Tx
Rx
RTIP
RRING
XRT83VSH28
8-CHANNEL E1 SHORT-HAUL LINE INTERFACE UNIT
4.1.3
REV. 2.0.0
Digital Loopback
With digital loopback activated, the transmit input data at TCLK/TPOS/TNEG is looped back to the receive
output data at RCLK/RPOS/RNEG. The digital loopback mode includes the Transmit JA (if enabled). The
receive input data at RTIP/RRING is ignored while valid transmit output data continues to be sent to the line. A
simplified block diagram of digital loopback is shown in Figure 21.
FIGURE 21. SIMPLIFIED BLOCK DIAGRAM OF DIGITAL LOOPBACK
QRSS
4.1.4
TAOS
TCLK
TPOS
TNEG
Encoder
JA
Timing
Control
RCLK
RPOS
RNEG
Decoder
JA
Data and
Clock
Recovery
TTIP
TRING
Tx
Rx
RTIP
RRING
Dual Loopback
With dual loopback activated, the remote loopback is combined with the digital loopback. A simplified block
diagram of dual loopback is shown in Figure 22.
FIGURE 22. SIMPLIFIED BLOCK DIAGRAM OF DUAL LOOPBACK
QRSS
TAOS
TCLK
TPOS
TNEG
Encoder
JA
Timing
Control
RCLK
RPOS
RNEG
Decoder
JA
Data and
Clock
Recovery
33
Tx
Rx
TTIP
TRING
RTIP
RRING
XRT83VSH28
8-CHANNEL E1 SHORT-HAUL LINE INTERFACE UNIT
REV. 2.0.0
4.2
Line Card Redundancy
Telecommunication system design requires signal integrity and reliability. When an E1 primary line card has a
failure, it must be swapped with a backup line card while maintaining connectivity to a backplane without losing
data. System designers can achieve this by implementing common redundancy schemes with the
XRT83VSH28 LIU. EXAR offers features that are tailored to redundancy applications while reducing the
number of components and providing system designers with solid reference designs.
RLOS and DMO
If an RLOS or DMO condition occurs, the XRT83VSH28 reports the alarm to the individual status registers on a
per channel basis. However, for redundancy applications, an RLOS or DMO alarm can be used to initiate an
automatic switch to the back up card. For this application, two global pins RLOS and DMO are used to indicate
that one of the 8-channels has an RLOS or DMO condition.
Typical Redundancy Schemes
1:1 One backup card for every primary card (Facility Protection)
1+1 One backup card for every primary card (Line Protection)
·N+1 One backup card for N primary cards
4.2.1
1:1 and 1+1 Redundancy Without Relays
The 1:1 facility protection and 1+1 line protection have one backup card for every primary card. When using
1:1 or 1+1 redundancy, the backup card has its transmitters tri-stated and its receivers in high impedance. This
eliminates the need for external relays and provides one bill of materials for all interface modes of operation.
For 1+1 line protection, the receiver inputs on the backup card have the ability to monitor the line for bit errors
while in high impedance. The transmit and receive sections of the LIU device are described separately.
4.2.2
Transmit Interface with 1:1 and 1+1 Redundancy
The transmitters on the backup card should be tri-stated. Select the appropriate impedance for the desired
mode of operation. A 0.68uF capacitor is used in series with TTIP for blocking DC bias. See Figure 23. for a
simplified block diagram of the transmit section for a 1:1 and 1+1 redundancy.
FIGURE 23. SIMPLIFIED BLOCK DIAGRAM OF THE TRANSMIT INTERFACE FOR 1:1 AND 1+1 REDUNDANCY
Backplane Interface
Primary Card
XRT83VSH28
1:2
Tx
0.68uF
E1 Line
Internal Impedence
Backup Card
XRT83VSH28
1:2
Tx
0.68uF
Internal Impedence
34
XRT83VSH28
8-CHANNEL E1 SHORT-HAUL LINE INTERFACE UNIT
4.2.3
REV. 2.0.0
Receive Interface with 1:1 and 1+1 Redundancy
The receivers on the backup card should be programmed for "High" impedance. Since there is no external
resistor in the circuit, the receivers on the backup card will not load down the line interface. This key design
feature eliminates the need for relays and provides one bill of materials for all interface modes of operation.
Select the impedance for the desired mode of operation. To swap the primary card, set the backup card to
internal impedance, then the primary card to "High" impedance. See Figure 24. for a simplified block diagram
of the receive section for a 1:1 redundancy scheme.
FIGURE 24. SIMPLIFIED BLOCK DIAGRAM OF THE RECEIVE INTERFACE FOR 1:1 AND 1+1 REDUNDANCY
Backplane Interface
Primary Card
XRT83VSH28
1:1
E1 Line
Rx
Internal Impedence
XRT83VSH28
Backup Card
1:1
Rx
"High" Impedence
35
XRT83VSH28
8-CHANNEL E1 SHORT-HAUL LINE INTERFACE UNIT
REV. 2.0.0
4.2.4
N+1 Redundancy Using External Relays
N+1 redundancy has one backup card for N primary cards. Due to impedance mismatch and signal contention,
external relays are necessary when using this redundancy scheme. The relays create complete isolation
between the primary cards and the backup card. This allows all transmitters and receivers on the primary cards
to be configured in internal impedance, providing one bill of materials for all interface modes of operation. The
transmit and receive sections of the LIU device are described separately.
4.2.5
Transmit Interface with N+1 Redundancy
For N+1 redundancy, the transmitters on all cards should be programmed for internal impedance. The
transmitters on the backup card do not have to be tri-stated. To swap the primary card, close the desired
relays, and tri-state the transmitters on the failed primary card. A 0.68uF capacitor is used in series with TTIP
for blocking DC bias. See Figure 25 for a simplified block diagram of the transmit section for an N+1
redundancy scheme.
FIGURE 25. SIMPLIFIED BLOCK DIAGRAM OF THE TRANSMIT INTERFACE FOR N+1 REDUNDANCY
Backplane Interface
Line Interface Card
Primary Card
XRT83VSH28
1:2
Tx
0.68uF
E1 Line
Internal
Impedence
XRT83VSH28
Primary Card
1:2
Tx
0.68uF
E1 Line
Internal
Impedence
Primary Card
XRT83VSH28
1:2
Tx
0.68uF
E1 Line
Internal
Impedence
Backup Card
XRT83VSH28
Tx
0.68uF
Internal
Impedence
36
XRT83VSH28
8-CHANNEL E1 SHORT-HAUL LINE INTERFACE UNIT
4.2.6
REV. 2.0.0
Receive Interface with N+1 Redundancy
For N+1 redundancy, the receivers on the primary cards should be programmed for internal impedance. The
receivers on the backup card should be programmed for "High" impedance mode. To swap the primary card,
set the backup card to internal impedance, then the primary card to "High" impedance. See Figure 26 for a
simplified block diagram of the receive section for a N+1 redundancy scheme.
FIGURE 26. SIMPLIFIED BLOCK DIAGRAM OF THE RECEIVE INTERFACE FOR N+1 REDUNDANCY
Backplane Interface
Line Interface Card
Primary Card
XRT83VSH28
1:1
Rx
E1 Line
Internal
Impedence
Primary Card
XRT83VSH28
1:1
E1 Line
Rx
Internal
Impedence
Primary Card
XRT83VSH28
1:1
Rx
E1 Line
Internal
Impedence
Backup Card
XRT83VSH28
Rx
"High"
Impedence
37
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8-CHANNEL E1 SHORT-HAUL LINE INTERFACE UNIT
REV. 2.0.0
4.3
Power Failure Protection
For 1:1 or 1+1 line card redundancy in E1 applications, power failure could cause a line card to change the
characteristics of the line impedance, causing a degradation in system performance. The XRT83VSH28 was
designed to ensure reliability during power failures. The LIU has patented high impedance circuits that allow
the receiver inputs and the transmitter outputs to be in "High" impedance when the LIU experiences a power
failure or when the LIU is powered off.
NOTE: For power failure protection, a transformer must be used to couple to the line interface. See the TAN-56 application
note for more details.
4.4
Overvoltage and Overcurrent Protection
Physical layer devices such as LIUs that interface to telecommunications lines are exposed to overvoltage
transients posed by environmental threats. An Overvoltage transient is a pulse of energy concentrated over a
small period of time, usually under a few milliseconds. These pulses are random and exceed the operating
conditions of CMOS transceiver ICs. Electronic equipment connecting to data lines are susceptible to many
forms of overvoltage transients such as lightning, AC power faults and electrostatic discharge (ESD). There are
three important standards when designing a telecommunications system to withstand overvoltage transients.
UL1950 and FCC Part 68
Telcordia (Bellcore) GR-1089
ITU-T K.20, K.21 and K.41
4.5
Non-Intrusive Monitoring
In non-intrusive monitoring applications, the transmitters are shut off by setting TxON "Low". The receivers
must be actively receiving data without interfering with the line impedance. The XRT83VSH28’s internal
termination ensures that the line termination meets E1 specifications for 75 or 120 while monitoring the
data stream. System integrity is maintained by placing the non-intrusive receiver in "High" impedance,
equivalent to that of a 1+1 redundancy application. A simplified block diagram of non-intrusive monitoring is
shown in Figure 27.
FIGURE 27. SIMPLIFIED BLOCK DIAGRAM OF A NON-INTRUSIVE MONITORING APPLICATION
XRT83VSH28
Data Traffic
Line Card Transceiver
Node
XRT83VSH28
Non-Intrusive Receiver
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8-CHANNEL E1 SHORT-HAUL LINE INTERFACE UNIT
REV. 2.0.0
5.0 MICROPROCESSOR INTERFACE
The microprocessor interface can be accessed through a standard serial interface (BGA Package Only) or a
standard parallel microprocessor interface. The SER_PAR pin is used to select between the two. By default,
the chip is configured in the Parallel Microprocessor interace. For Serial communication, this pin must be
pulled “High”.
5.1
Serial Microprocessor Interface Block (BGA Package Only)
The serial microprocessor uses a standard 3-pin serial port with CS, SCLK, and SDI for programming the LIU.
Optional pins such as SDO, INT, and RESET allow the ability to read back contents of the registers, monitor
the LIU via an interrupt pin, and reset the LIU to its default configuration by pulling reset "Low" for more than
10S. A simplified block diagram of the Serial Microprocessor is shown in Figure 28.
FIGURE 28. SIMPLIFIED BLOCK DIAGRAM OF THE SERIAL MICROPROCESSOR INTERFACE
SDO
CS
SCLK
INT
SDI
Serial
Microprocessor
Interface
SER_PAR
HW/Host
RESET
5.1.1
Serial Timing Information
The serial port requires 24 bits of data applied to the SDI (Serial Data Input) pin. The Serial Microprocessor
samples SDI on the rising edge of SCLK (Serial Clock Input). The data is not latched into the device until all 24
bits of serial data have been sampled. A timing diagram of the Serial Microprocessor is shown in Figure 29.
FIGURE 29. TIMING DIAGRAM FOR THE SERIAL MICROPROCESSOR INTERFACE
CS
8-Bit Address
R/W
ADDR[0] - ADDR[7]
SDI
7-Bit Don't Care
8-Bit Data
Don't Care
DATA[0] - DATA[7]
1=Read
0=Write
Readback
DATA[0] - DATA[7]
SDO
SCLK
NOTE: For applications without a free running SCLK, a minimum of 1 SCLK pulse must be applied when CS is “High”,
befrore pulling CS “Low”.
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XRT83VSH28
8-CHANNEL E1 SHORT-HAUL LINE INTERFACE UNIT
REV. 2.0.0
5.1.2
24-Bit Serial Data Input Descritption
The serial data input is sampled on the rising edge of SCLK. In readback mode, the serial data output is
updated on the falling edge of SCLK. The serial data must be applied to the LIU LSB first. The 24 bits of serial
data are described below.
5.1.3
ADDR[7:0] (SCLK1 - SCLK8)
The first 8 SCLK cycles are used to provide the address to which a Read or Write operation will occur.
ADDR[0] (LSB) must be sent to the LIU first followed by ADDR[1] and so forth until all 8 address bits have been
sampled by SCLK.
5.1.4
R/W (SCLK9)
The next serial bit applied to the LIU informs the microprocessor that a Read or Write operation is desired. If
the R/W bit is set to “0”, the microprocessor is configured for a Write operation. If the R/W bit is set to “1”, the
microprocessor is configured for a Read operation.
5.1.5
Dummy Bits (SCLK10 - SCLK16)
The next 7 SCLK cycles are used as dummy bits. Seven bits were chosen so that the serial interface can easily
be divided into three 8-bit words to be compliant with standard serial interface devices. The state of these bits
are ignored and can hold either “0” or “1” during both Read and Write operations.
5.1.6
DATA[7:0] (SCLK17 - SCLK24)
The next 8 SCLK cycles are used to provide the data to be written into the internal register chosen by the
address bits. DATA[0] (LSB) must be sent to the LIU first followed by DATA[1] and so forth until all 8 data bits
have been sampled by SCLK. Once 24 SCLK cycles have been completed, the LIU holds the data until CS is
pulled “High” whereby, the serial microprocessor latches the data into the selected internal register.
5.1.7
8-Bit Serial Data Output Description
The serial data output is updated on the falling edge of SCLK17 - SCLK24 if R/W is set to “1”. DATA[0] (LSB) is
provided on SCLK17 to the SDO pin first followed by DATA[1] and so forth until all 8 data bits have been
updated. The SDO pin allows the user to read the contents stored in individual registers by providing the
desired address on the SDI pin during the Read cycle.
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8-CHANNEL E1 SHORT-HAUL LINE INTERFACE UNIT
REV. 2.0.0
FIGURE 30. TIMING DIAGRAM FOR THE MICROPROCESSOR SERIAL INTERFACE
t28
t21
CS
t26
t24
SCLK
t22
SDI
t25
t23
ADDR 6
ADDR 7
R/w
D1
D2
CS
SCLK
t29
SDO
Hi-Z
t31
D0
D7
Don’t Care (Read mode)
SDI
TABLE 9: MICROPROCESSOR SERIAL INTERFACE TIMINGS ( TA = 250C, VDD=3.3V± 5% AND LOAD = 10PF)
SYMBOL
PARAMETER
MIN.
TYP.
MAX
UNITS
t21
CS Low to Rising Edge of SClk
5
ns
t22
SDI to Rising Edge of SClk
5
ns
t23
SDI to Rising Edge of SClk Hold Time
5
ns
t24
SClk "Low" Time
20
ns
t25
SClk "High" Time
20
ns
t26
SClk Period
40
ns
t28
CS Inactive Time
40
ns
t29
Falling Edge of SClk to SDO Valid Time
5
ns
t31
Rising edge of CS to High Z
5
ns
41
XRT83VSH28
8-CHANNEL E1 SHORT-HAUL LINE INTERFACE UNIT
REV. 2.0.0
5.2
Parallel Microprocessor Interface Block
The Parallel Microprocessor Interface section supports communication between the local microprocessor (µP)
and the LIU. The XRT83VSH28 supports an Intel asynchronous interface, Motorola 68K asynchronous, and an
Intel/Motorola interface. The microprocessor interface is selected by the state of the µPTS[1:0] input pins.
Selecting the microprocessor interface is shown in Table 10.
TABLE 10: SELECTING THE MICROPROCESSOR INTERFACE MODE
µPTS[1:0]
MICROPROCESSOR MODE
0h (00)
Intel 68HC11, 8051, 80C188
(Asynchronous)
1h (01)
Motorola 68K (Asynchronous)
2h (10)
Power PC 403 (Synchronous)
3h (11)
MPC8xx (Synchronous)
The XRT83VSH28 uses multipurpose pins to configure the device appropriately. The local µP configures the
LIU by writing data into specific addressable, on-chip Read/Write registers. The microprocessor interface
provides the signals which are required for a general purpose microprocessor to read or write data into these
registers. The microprocessor interface also supports polled and interrupt driven environments. A simplified
block diagram of the microprocessor is shown in Figure 31.
FIGURE 31. SIMPLIFIED BLOCK DIAGRAM OF THE MICROPROCESSOR INTERFACE BLOCK
CS
WR_R/W
RD_DS
ALE
ADDR[7:0]
DATA[7:0]
µPclk
Microprocessor
Interface
µPTS [1:0]
Reset
RDY
INT
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XRT83VSH28
8-CHANNEL E1 SHORT-HAUL LINE INTERFACE UNIT
5.3
REV. 2.0.0
The Microprocessor Interface Block Signals
The LIU may be configured into different operating modes and have its performance monitored by software
through a standard microprocessor using data, address and control signals. These interface signals are
described below in Table 11, Table 12, and Table 13. The microprocessor interface can be configured to
operate in Intel mode or Motorola mode. When the microprocessor interface is operating in Intel mode, some
of the control signals function in a manner required by the Intel 80xx family of microprocessors. Likewise, when
the microprocessor interface is operating in Motorola mode, then these control signals function in a manner as
required by the Motorola microprocessors. (For using a Motorola 68K asynchronous processor, see
Figure 33 and Table 15) Table 11 lists and describes those microprocessor interface signals whose role is
constant across the two modes. Table 12 describes the role of some of these signals when the microprocessor
interface is operating in the Intel mode. Likewise, Table 13 describes the role of these signals when the
microprocessor interface is operating in the Motorola Power PC mode.
TABLE 11: XRT83VSH28 MICROPROCESSOR INTERFACE SIGNALS THAT EXHIBIT CONSTANT ROLES IN BOTH INTEL
AND MOTOROLA MODES
PIN NAME
TYPE
DESCRIPTION
µPTS[1:0]
I
Microprocessor Interface Mode Select Input pins
These three pins are used to specify the microprocessor interface mode. The relationship
between the state of these three input pins, and the corresponding microprocessor mode is
presented in Table 10.
DATA[7:0]
I/O
ADDR[7:0]
I
Eight-Bit Address Bus Inputs
The XRT83VSH28 LIU microprocessor interface uses a direct address bus. This address bus
is provided to permit the user to select an on-chip register for Read/Write access.
CS
I
Chip Select Input
This active low signal selects the microprocessor interface of the XRT83VSH28 LIU and
enables Read/Write operations with the on-chip register locations.
Bi-Directional Data Bus for register "Read" or "Write" Operations.
TABLE 12: INTEL MODE: MICROPROCESSOR INTERFACE SIGNALS
XRT83VSH28
INTEL
PIN NAME EQUIVALENT PIN
TYPE
DESCRIPTION
ALE
ALE
I
Address-Latch Enable: This active high signal is used to latch the contents on
the address bus ADDR[7:0]. The contents of the address bus are latched into the
ADDR[7:0] inputs on the falling edge of ALE.
RD_DS
RD
I
Read Signal: This active low input functions as the read signal from the local µP.
When this pin is pulled “Low” (if CS is “Low”) the LIU is informed that a read operation has been requested and begins the process of the read cycle.
WR_R/W
WR
I
Write Signal: This active low input functions as the write signal from the local µP.
When this pin is pulled “Low” (if CS is “Low”) the LIU is informed that a write
operation has been requested and begins the process of the write cycle.
RDY
RDY
O
Ready Output: This active low signal is provided by the LIU device. It indicates
that the current read or write cycle is complete, and the LIU is waiting for the next
command.
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8-CHANNEL E1 SHORT-HAUL LINE INTERFACE UNIT
REV. 2.0.0
TABLE 13: MOTOROLA MODE: MICROPROCESSOR INTERFACE SIGNALS
XRT83VSH28 MOTOROLA
PIN NAME EQUIVALENT PIN
TYPE
DESCRIPTION
ALE
AS
I
Address Strobe: This active high signal is used to latch the contents on the
address bus ADDR[7:0]. The contents of the address bus are latched into the
ADDR[7:0] inputs on the falling edge of TS.
WR_R/W
R/W
I
Read/Write: This input pin from the local µP is used to inform the LIU
whether a Read or Write operation has been requested. When this pin is
pulled “High”, DS will initiate a read operation. When this pin is pulled
“Low”, DS will initiate a write operation.
RD_DS
DS
I
Data Strobe: This active low input functions as the read or write signal from the
local µP dependent on the state of R/W. When DS is pulled “Low” (If CS
is “Low”) the LIU begins the read or write operation.
RDY
DTACK
O
Data Transfer Acknowledge: This active low signal is provided by the LIU
device. It indicates that the current read or write cycle is complete, and the LIU is
waiting for the next command.
44
XRT83VSH28
8-CHANNEL E1 SHORT-HAUL LINE INTERFACE UNIT
5.4
REV. 2.0.0
Intel Mode Programmed I/O Access (Asynchronous)
If the LIU is interfaced to an Intel type µP, then it should be configured to operate in the Intel mode. Intel type
Read and Write operations are described below.
Intel Mode Read Cycle
Whenever an Intel-type µP wishes to read the contents of a register, it should do the following.
1. Place the address of the target register on the address bus input pins ADDR[7:0].
2. While the µP is placing this address value on the address bus, the address decoding circuitry should
assert the CS pin of the LIU, by toggling it "Low". This action enables further communication between the
µP and the LIU microprocessor interface block.
3. Toggle the ALE input pin "High". This step enables the address bus input drivers, within the microprocessor interface block of the LIU.
4. The µP should then toggle the ALE pin "Low". This step causes the LIU to latch the contents of the address
bus into its internal circuitry. At this point, the address of the register has now been selected.
5. Next, the µP should indicate that this current bus cycle is a Read operation by toggling the RD input pin
"Low". This action also enables the bi-directional data bus output drivers of the LIU.
6. After the µP toggles the Read signal "Low", the LIU will toggle the RDY output pin "Low". The LIU does this
in order to inform the µP that the data is available to be read by the µP, and that it is ready for the next command.
7. After the µP detects the RDY signal and has read the data, it can terminate the Read Cycle by toggling the
RD input pin "High".
NOTE: ALE can be tied “High” if this signal is not available.
The Intel Mode Write Cycle
Whenever an Intel type µP wishes to write a byte or word of data into a register within the LIU, it should do the
following.
1. Place the address of the target register on the address bus input pins ADDR[7:0].
2. While the µP is placing this address value on the address bus, the address decoding circuitry should
assert the CS pin of the LIU, by toggling it "Low". This action enables further communication between the
µP and the LIU microprocessor interface block.
3. Toggle the ALE input pin "High". This step enables the address bus input drivers, within the microprocessor interface block of the LIU.
4. The µP should then toggle the ALE pin "Low". This step causes the LIU to latch the contents of the address
bus into its internal circuitry. At this point, the address of the register has now been selected.
5. The µP should then place the byte or word that it intends to write into the target register, on the bi-directional data bus DATA[7:0].
6. Next, the µP should indicate that this current bus cycle is a Write operation by toggling the WR input pin
"Low". This action also enables the bi-directional data bus input drivers of the LIU.
7. After the µP toggles the Write signal "Low", the LIU will toggle the RDY output pin "Low". The LIU does this
in order to inform the µP that the data has been written into the internal register location, and that it is ready
for the next command.
NOTE: ALE can be tied “High” if this signal is not available.
The Intel Read and Write timing diagram is shown in Figure 32. The timing specifications are shown in
Table 14.
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XRT83VSH28
8-CHANNEL E1 SHORT-HAUL LINE INTERFACE UNIT
REV. 2.0.0
FIGURE 32. INTEL µP INTERFACE SIGNALS DURING PROGRAMMED I/O READ AND WRITE OPERATIONS
READ OPERATION
ALE = 1
WRITE OPERATION
t0
t0
ADDR[7:0]
Valid Address
Valid Address
CS
Valid Data for Readback
DATA[7:0]
Data Available to Write Into the LIU
t1
RD
t3
WR
t2
t4
RDY
TABLE 14: INTEL MICROPROCESSOR INTERFACE TIMING SPECIFICATIONS
SYMBOL
PARAMETER
MIN
MAX
UNITS
t0
Valid Address to CS Falling Edge
0
-
ns
t1
CS Falling Edge to RD Assert
65
-
ns
t2
RD Assert to RDY Assert
-
90
ns
RD Pulse Width (t2)
90
-
ns
t3
CS Falling Edge to WR Assert
65
-
ns
t4
WR Assert to RDY Assert
-
90
ns
90
-
ns
NA
NA
WR Pulse Width (t4)
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XRT83VSH28
8-CHANNEL E1 SHORT-HAUL LINE INTERFACE UNIT
5.5
REV. 2.0.0
Motorola Mode Programmed I/O Access (Asynchronous)
If the LIU is interfaced to a Motorola type µP, it should be configured to operate in the Motorola mode. Motorola
type programmed I/O Read and Write operations are described below.
Motorola Mode Read Cycle
Whenever a Motorola type µP wishes to read the contents of a register, it should do the following.
1. Place the address of the target register on the address bus input pins ADDR[7:0].
2. While the µP is placing this address value on the address bus, the address decoding circuitry should
assert the CS pin of the LIU, by toggling it "Low". This action enables further communication between the
µP and the LIU microprocessor interface block.
3. The µP should then toggle the AS pin "Low". This step causes the LIU to latch the contents of the address
bus into its internal circuitry. At this point, the address of the register has now been selected.
4. Next, the µP should indicate that this current bus cycle is a Read operation by pulling the R/W input pin
"High".
5. Toggle the DS input pin "Low". This action enables the bi-directional data bus output drivers of the LIU.
6. After the µP toggles the DS signal "Low", the LIU will toggle the DTACK output pin "Low". The LIU does
this in order to inform the µP that the data is available to be read by the µP, and that it is ready for the next
command.
7. After the µP detects the DTACK signal and has read the data, it can terminate the Read Cycle by toggling
the DS input pin "High".
Motorola Mode Write Cycle
Whenever a motorola type µP wishes to write a byte or word of data into a register within the LIU, it should do
the following.
1. Place the address of the target register on the address bus input pins ADDR[7:0].
2. While the µP is placing this address value on the address bus, the address decoding circuitry should
assert the CS pin of the LIU, by toggling it "Low". This action enables further communication between the
µP and the LIU microprocessor interface block.
3. The µP should then toggle the AS pin "Low". This step causes the LIU to latch the contents of the address
bus into its internal circuitry. At this point, the address of the register has now been selected.
4. Next, the µP should indicate that this current bus cycle is a Write operation by pulling the R/W input pin
"Low".
5. Toggle the DS input pin "Low". This action enables the bi-directional data bus output drivers of the LIU.
6. After the µP toggles the DS signal "Low", the LIU will toggle the DTACK output pin "Low". The LIU does
this in order to inform the µP that the data has been written into the internal register location, and that it is
ready for the next command.
7. After the µP detects the DTACK signal and has read the data, it can terminate the Read Cycle by toggling
the DS input pin "High".
The Motorola Read and Write timing diagram is shown in Figure 33. The timing specifications are shown in
Table 15.
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8-CHANNEL E1 SHORT-HAUL LINE INTERFACE UNIT
REV. 2.0.0
FIGURE 33. MOTOROLA 68K µP INTERFACE SIGNALS DURING PROGRAMMED I/O READ AND WRITE OPERATIONS
MOTOROLA ASYCHRONOUS MODE
READ OPERATION
AS
WRITE OPERATION
t0
t0
Valid Address
ADDR[7:0]
Valid Address
t3
t3
CS
Valid Data for Readback
DATA[7:0]
t1
Data Available to Write Into the LIU
t1
RD_DS
WR_R/W
t2
RDY_DTACK
t2
TABLE 15: MOTOROLA 68K MICROPROCESSOR INTERFACE TIMING SPECIFICATIONS
SYMBOL
PARAMETER
MIN
MAX
UNITS
t0
Valid Address to CS Falling Edge
0
-
ns
t1
CS Falling Edge to DS (Pin RD_DS) Assert
65
-
ns
t2
DS Assert to DTACK Assert
-
90
ns
DS Pulse Width (t2)
90
-
ns
CS Falling Edge to AS (Pin ALE) Falling Edge
0
-
ns
NA
t3
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XRT83VSH28
8-CHANNEL E1 SHORT-HAUL LINE INTERFACE UNIT
5.6
REV. 2.0.0
PowerPC 403 Synchronous Mode:
In PowerPC mode the active signals are ADDR[7:0], DATA[7:0], CS, R/W (Intel WR), WE (Intel RD), RDY and
PCLK. In this mode all input signals are sampled by the PCLK. For all inputs minimum setup time is 4ns and
minimum hold time is 3ns. Maximum PCLK frequency is 50 MHz.
A READ cycle starts with R/W being 'HIGH' and assertion of CS, address is assumed to be stable at this time
since CS is usually derived from the decoding the address bus.
Operation with wait-states is possible, provided the wait is longer than the minimum cycle time. Use of RDY is
recommended for timing efficiency since the read cycle time can vary depending on the internal address location
being accessed.
WRITE operation is identical to the READ operation except that the cycle starts with R/W being 'LOW', followed
by CS assertion further followed by assertion of WE. Data to be written at the addressed location should be valid
on the data bus at the time WE is asserted. WE should remain asserted until RDY is asserted by the device.
Following RDY assertion WE and CS may be de-asserted.
FIGURE 34. POWERPC 403 MODE TIMING - WRITE OPERATION
1
2
3
4
5
6
7
8
9
10
PClk
ADDR[7:0]
CS
R/W
WE
D[7:0]
t23
RDY
t25
t24
8 PClk Cycles
Note: The value for t25 through t38 can be found in Table 16.
Table 16
Power PC403 Mode Timing - Write Operation
Test Conditions: TA = 25°C, VCC = 3.3V±5% and 1.8V±5%, unless otherwise specified
Timing
Description
Min.
Typ.
Max.
Units
t23
R/W "Low" to rising edge of PCLK set-up time (Write Operation)
5
-
-
ns
t24
CS "Low" to rising edge of PCLK set-up time
5
-
-
ns
t25
Rising edge of PCLK to RDY "Low" delay
4
-
-
ns
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8-CHANNEL E1 SHORT-HAUL LINE INTERFACE UNIT
REV. 2.0.0
FIGURE 35. POWERPC 403 MODE TIMING - READ OPERATION
1
2
3
4
5
6
7
8
9
10
PClk
A[17:0]
R/W
WE
t26
OE
After 1 PClk of CS going "Low"
CS
t27
7 PClk Cycles
NOT Valid
D[7:0]
Valid
RDY
t24
8 PClk Cycles
t25
Note: The value for t25 through t38 can be found in Table 17.
Table 17
Power PC403 Mode Timing - Read Operation
Test Conditions: TA = 25°C, VCC = 3.3V±5% and 1.8V±5%, unless otherwise specified
Timing
Description
Min.
Typ.
Max.
Units
t24
CS "Low" to rising edge of PCLK set-up time
5
-
-
ns
t25
Rising edge of PCLK to RDY “Low” delay
4
-
-
ns
t26
OE “Low” to rising edge of PCLK
5
-
-
ns
t27
R/W “High” to rising edge of PCLK set-up time
5
-
-
ns
50
XRT83VSH28
8-CHANNEL E1 SHORT-HAUL LINE INTERFACE UNIT
5.7
REV. 2.0.0
MICROPROCESSOR INTERFACE TIMING - MCP860 SYNCHRONOUS MODE
In MPC86x mode the active signals are ADDR[17:0], DATA[7:0], CS, RW, WE, DBEN, TA and PCLK. In this
mode all input signals are sampled by the PCLK. For all inputs minimum setup time is 4ns and minimum hold
time is 3ns. Maximum PCLK frequency is 70 MHz.
A READ cycle starts with RW being 'HIGH' and assertion of CS, address is assumed to be stable at this time
since CS is usually derived from the decoding the address bus.
Following falling edge of CS, DBEN is asserted for the READ operation. DBEN must remain asserted until TA
is asserted by the XRT86SH221 device, which indicates DATA from the addressed location is available on the
data bus. DBEN and CS can be de-asserted when the data has been read by the processor. WE should be high
during the entire read cycle.
Operation with wait-states is also possible, provided the wait is longer than the minimum cycle time. Use of TA
is recommended for timing efficiency since the read cycle time can vary depending on the internal address
location being accessed.
WRITE operation is identical to read operation except that the cycle starts with RW being 'LOW', followed by
CS assertion further followed by assertion of WE. Data to be written at the addressed location should be valid
on the data bus at the time WE is asserted. WE should remain asserted until TA is asserted by the
XRT86SH221 device. Following assertion of TA WE and CS may be de-asserted. DBEN should be high during
the entire write cycle.
FIGURE 36. MPC86X MODE TIMING - WRITE OPERATION
1
2
3
4
5
6
7
8
9
10
PClk
A[17:0]
CS
R/W
After 1 PClk Cycle
WE
D[7:0]
OE
RDY
t23
t25
t24
8 PClk Cycles
NOTE: PClk = 33Mhz
Table 18
MPC86X Mode Timing - Write Operation
Test Conditions: TA = 25°C, VCC = 3.3V±5% and 1.8V±5%, unless otherwise specified
Timing
Description
Min.
Typ.
Max.
Units
t23
R/W "Low" to rising edge of PCLK set-up time (Write
Operation)
5
-
-
ns
t24
CS "Low" to rising edge of PCLK set-up time
4
-
-
ns
t25
Rising edge of PCLK to RDY “High”delay
4
-
-
ns
51
XRT83VSH28
8-CHANNEL E1 SHORT-HAUL LINE INTERFACE UNIT
REV. 2.0.0
FIGURE 37. MPC86X MODE TIMING - READ OPERATION
1
2
3
4
5
6
7
8
9
10
PClk
A[17:0]
R/W
WE
t26
OE
After 1 PClk of CS going "Low"
CS
t27
7 PClk Cycles
NOT Valid
D[7:0]
Valid
RDY
t24
8 PClk Cycles
t25
Table 19
MPC86X Timing Information - Read Operation
Test Conditions: TA = 25°C, VCC = 3.3V±5% and 1.8V±5%, unless otherwise specified
Timing
Description
Min.
Typ.
Max.
Units
t24
CS "Low" to rising edge of PCLK set-up time
5
-
-
ns
t25
Rising edge of PCLK to RDY “High” delay
4
-
-
ns
t26
OE “Low” to rising edge of PCLK
5
-
-
ns
t27
R/W “High” to rising edge of PCLK set-up time
5
-
-
ns
52
XRT83VSH28
8-CHANNEL E1 SHORT-HAUL LINE INTERFACE UNIT
REV. 2.0.0
TABLE 20: MICROPROCESSOR REGISTER ADDRESS (ADDR[7:0])
REGISTER
NUMBER
ADDRESS (HEX)
0 - 15
0x00 - 0x0F
Channel 0 Control Registers
16 - 31
0x10 - 0x1F
Channel 1 Control Registers
32 - 47
0x20 - 0x2F
Channel 2 Control Registers
48 - 63
0x30 - 0x3F
Channel 3 Control Registers
64 - 79
0x40 - 0x4F
Channel 4 Control Registers
80 - 95
0x50 - 0x5F
Channel 5 Control Registers
96 - 111
0x60 - 0x6F
Channel 6 Control Registers
112 - 127
0x70 - 0x7F
Channel 7 Control Registers
128 - 142
0x80 - 0x8E
Global Control Registers Applied to All 8 Channels
143 - 253
0x8F - 0xFD
R/W Registers Reserved for Testing (Except 0xC0h)
254
0xFE
Device "ID"
255
0xFF
Device "Revision ID"
FUNCTION
TABLE 21: MICROPROCESSOR REGISTER CHANNEL DESCRIPTION
REG
ADDR TYPE
D7
D6
D5
D4
D3
D2
D1
D0
Channel 0 Control Registers (0x00 - 0x0F)
0
0x00
R/W
QRSS/PRBS
PRBS_Rx/Tx
RxON
EQC4
EQC3
EQC2
EQC1
EQC0
1
0x01
R/W
RxTSEL
TxTSEL
Reserved
TERSEL
JASEL1
JASEL0
JABW
FIFOS
2
0x02
R/W
INVQRSS
TxTEST2
TxTEST1
TxTEST0
TxON
LOOP2
LOOP1
LOOP0
3
0x03
R/W
Reserved
Reserved
CODES
RxRES1
RxRES0
INSBPV
INSBER
Reserved
4
0x04
R/W
Reserved
DMOIE
FLSIE
LCV/OFIE
Reserved
AISIE
RLOSIE
QRPDIE
5
0x05
RO
Reserved
DMO
FLS
LCV/OF
Reserved
AIS
RLOS
QRPD
6
0x06
RUR
Reserved
DMOIS
FLSIS
LCV/OFIS
Reserved
AISIS
RLOSIS
QRPDIS
7
0x07
RO
Reserved
Reserved
Reserved
Reserved
Reserved
Reserved
Reserved
Reserved
8
0x08
R/W
Reserved
Reserved
Reserved
Reserved
Reserved
Reserved
Reserved
Reserved
9
0x09
R/W
Reserved
Reserved
Reserved
Reserved
Reserved
Reserved
Reserved
Reserved
10
0x0A
R/W
Reserved
Reserved
Reserved
Reserved
Reserved
Reserved
Reserved
Reserved
11
0x0B
R/W
Reserved
Reserved
Reserved
Reserved
Reserved
Reserved
Reserved
Reserved
12
0x0C
R/W
Reserved
Reserved
Reserved
Reserved
Reserved
Reserved
Reserved
Reserved
13
0x0D
R/W
Reserved
Reserved
Reserved
Reserved
Reserved
Reserved
Reserved
Reserved
14
0x0E
R/W
Reserved
Reserved
Reserved
Reserved
Reserved
Reserved
Reserved
Reserved
15
0x0F
R/W
Reserved
Reserved
Reserved
Reserved
Reserved
Reserved
Reserved
Reserved
Channel (1 -7) Control Registers (0x10 - 0x7F) See Channel 0
53
XRT83VSH28
8-CHANNEL E1 SHORT-HAUL LINE INTERFACE UNIT
REV. 2.0.0
TABLE 21: MICROPROCESSOR REGISTER CHANNEL DESCRIPTION
REG
ADDR TYPE
D7
D6
D5
D4
D3
D2
D1
D0
Global Control Registers for All 8 Channels
128
0x80
R/W
SR/DR
ATAOS
RCLKE
TCLKE
DATAP
Reserved
GIE
SRESET
129
0x81
R/W
OVFLO/LCV
Reserved
Reserved
Reserved
Reserved
RxMUTE
EXLOS
ICT
130
0x82
R/W
TxONCNTL
TERCNTL
Reserved
Reserved
Reserved
Reserved
Reserved
Reserved
131
0x83
R/W
Reserved
Reserved
Reserved
Reserved
Reserved
Reserved
Reserved
Reserved
140
0x8C
R/W
Reserved
Reserved
Reserved
Reserved
LCVCH3
LCVCH2
LCVCH1
LCVCH0
141
0x8D
R/W
Reserved
Reserved
Reserved
allRST
allUPDATE
BYTEsel
chUPDATE
chRST
142
0x8E
RO
LCVCNT7
LCVCNT6
LCVCNT5
LCVCNT4
LCVCNT3
LCVCNT2
LCVCNT1
LCVCNT0
R/W Registers Reserved for Testing (0x8F - 0xFD)
254
0xFE
RO
Device "ID"
255
0xFF
RO
Device "Revision ID"
54
XRT83VSH28
8-CHANNEL E1 SHORT-HAUL LINE INTERFACE UNIT
5.8
REV. 2.0.0
Channel Control Registers
TABLE 22: MICROPROCESSOR REGISTER 0X00H BIT DESCRIPTION
CHANNEL 0-7 (0X00H-0X70H)
BIT
NAME
D7
QRSS/
PRBS
D6
FUNCTION
QRSS/PRBS Select Bits
These bits are used to select between QRSS and PRBS.
1 = QRSS
0 = PRBS
PRBS_Rx/ PRBS Receive/Transmit Select:
Tx
This bit is used to select where the output of the PRBS Generator
is directed if PRBS generation is enabled.
0 = Normal Operation - PRBS generator is output on TTIP and
TRING if PRBS generation is enabled.
1 = PRBS Generator is output on RPOS (based on TCLK); RNEG
is internally grounded, if PRBS generation is enabled.
Register
Type
Default
Value
(HW reset)
R/W
0
R/W
0
Bit 6 = "0"
+
PBRS
Generator
TTIP
-
Tx
TRING
Bit 6 = "1"
+
PBRS
Generator
-
RPOS
Rx
RNEG
NOTE: If PRBS generation is disabled, user should set this bit to ’0’
for normal operation.
D5
RxON
Receiver ON/OFF
Upon power up, the receiver is powered OFF. RxON is used to
turn the receiver ON or OFF if the hardware pin RxON is pulled
"High". If the hardware pin is pulled "Low", all receivers are turned
off.
0 = Receiver is Powered Off
1 = Receiver is Powered On
R/W
0
D4
D3
D2
D1
D0
EQC4
EQC3
EQC2
EQC1
EQC0
Cable Length Setting
R/W
0
0
0
0
0
The equalizer control bits are shown in Table 23 below.
55
XRT83VSH28
8-CHANNEL E1 SHORT-HAUL LINE INTERFACE UNIT
REV. 2.0.0
TABLE 23: CABLE LENGTH SETTING
EQC[4:0]
E1 MODE/RECEIVE SENSITIVITY
TRANSMIT LBO
CABLE
CODING
0x1Ch
E1 Short Haul/15dB
ITU G.703
75 Coax
HDB3
0x1Dh
E1 Short Haul/15dB
ITU G.703
120 TP
HDB3
TABLE 24: MICROPROCESSOR REGISTER 0X01H BIT DESCRIPTION
CHANNEL 0-7 (0X01H-0X71H)
Register
Type
Default
Value
(HW reset)
Receive Termination Select
Upon power up, the receiver is in "High" impedance. RxTSEL is
used to switch between the internal termination and "High" impedance.
0 = "High" Impedance
1 = Internal Termination
R/W
0
Transmit Termination Select
Upon power up, the transmitter is in "High" impedance. TxTSEL is
used to switch between the internal termination and "High" impedance.
0 = "High" Impedance
1 = Internal Termination
R/W
0
Reserved
Reserved
R/W
0
D4
TERSEL
Receive Line Impedance Select
TERSEL is used to select the line impedance for E1.
"0" = 75
"1" = 120
R/W
0
D3
D2
JASEL1
JASEL0
Jitter Attenuator Select
JASEL[1:0] are used to select the jitter attenuator in the transmit or
receive path. By default, the jitter attenuator is disabled.
R/W
0
BIT
NAME
FUNCTION
D7
RxTSEL
D6
TxTSEL
D5
JASEL1
JASEL0
JA PATH
0
0
Disabled
0
1
Transmit Path
1
0
Receive Path
1
1
Receive Path
56
XRT83VSH28
8-CHANNEL E1 SHORT-HAUL LINE INTERFACE UNIT
REV. 2.0.0
TABLE 24: MICROPROCESSOR REGISTER 0X01H BIT DESCRIPTION
CHANNEL 0-7 (0X01H-0X71H)
Register
Type
Default
Value
(HW reset)
Jitter Bandwidth
The jitter bandwidth is a global setting that is applied to both the
receiver and transmitter jitter attenuator.
0 = 10Hz
1 = 1.5Hz
R/W
0
FIFO Depth Select
The FIFO depth select is used to configure the part for a 32-bit or
64-bit FIFO (within the jitter attenuator blocks). The delay of the
FIFO is equal to ½ the FIFO depth. This is a global setting that is
applied to both the receiver and transmitter FIFO.
0 = 32-Bit
1 = 64-Bit
R/W
0
Register
Type
Default
Value
(HW reset)
BIT
NAME
FUNCTION
D1
JABW
D0
FIFOS
TABLE 25: MICROPROCESSOR REGISTER 0X02H BIT DESCRIPTION
CHANNEL 0-7 (0X02H-0X72H)
BIT
NAME
FUNCTION
D7
INVQRSS
QRSS inversion
INVQRSS is used to invert the transmit QRSS pattern set by the
TxTEST[2:0] bits. By default, INVQRSS is disabled and the QRSS
will be transmitted with normal polarity.
0 = Disabled
1 = Enabled
R/W
0
D6
D5
D4
TxTEST2
TxTEST1
TxTEST0
Test Code Pattern
TxTEST[2:0] are used to select a diagnostic test pattern to the line
(transmit outputs).
0XX = No Pattern
100 = Tx QRSS
101 = Tx TAOS
110 = Reserved
111 = Reserved
R/W
0
0
0
57
XRT83VSH28
8-CHANNEL E1 SHORT-HAUL LINE INTERFACE UNIT
REV. 2.0.0
TABLE 25: MICROPROCESSOR REGISTER 0X02H BIT DESCRIPTION
CHANNEL 0-7 (0X02H-0X72H)
Register
Type
Default
Value
(HW reset)
Transmit ON/OFF
Upon power up, the transmitters are powered off. This bit is used
to turn the transmitter for this channel On or Off.
0 = Transmitter is Powered OFF
1 = Transmitter is Powered ON
R/W
0
Loopback Diagnostic Select
LOOP[2:0] are used to select the loopback mode.
0XX = No Loopback
100 = Dual Loopback
101 = Analog Loopback
110 = Remote Loopback
111 = Digital Loopback
R/W
0
0
0
Register
Type
Default
Value
(HW reset)
BIT
NAME
FUNCTION
D3
TxOn
D2
D1
D0
LOOP2
LOOP1
LOOP0
TABLE 26: MICROPROCESSOR REGISTER 0X03H BIT DESCRIPTION
CHANNEL 0-7 (0X03H-0X73H)
BIT
NAME
FUNCTION
D[7:6]
Reserved
D5
CODES
Encoding/Decoding Select (Single Rail Mode Only)
0 = HDB3
1 = AMI Coding
R/W
0
D4
D3
RxRES1
RxRES0
Receive External Fixed Resistor
RxRES[1:0] are used to select the value for a high precision external resistor to improve return loss.
00 = None
01 = 320
10 = 280
11 = 190
R/W
0
0
D2
INSBPV
Insert Bipolar Violation
When this bit transitions from a "0" to a "1", a bipolar violation will
be inserted in the transmitted QRSS/PRBS pattern. The state of
this bit will be sampled on the rising edge of TCLK. To ensure
proper operation, it is recommended to write a "0" to this bit before
writing a "1".
R/W
0
This Register Bit is Not Used.
58
XRT83VSH28
8-CHANNEL E1 SHORT-HAUL LINE INTERFACE UNIT
REV. 2.0.0
TABLE 26: MICROPROCESSOR REGISTER 0X03H BIT DESCRIPTION
CHANNEL 0-7 (0X03H-0X73H)
BIT
NAME
FUNCTION
D1
INSBER
Insert Bit Error
When this bit transitions from a "0" to a "1", a bit error will be
inserted in the transmitted QRSS/PRBS pattern. The state of this
bit will be sampled on the rising edge of TCLK. To ensure proper
operation, it is recommended to write a "0" to this bit before writing
a "1".
D0
Reserved
Register
Type
Default
Value
(HW reset)
R/W
0
Register
Type
Default
Value
(HW reset)
TABLE 27: MICROPROCESSOR REGISTER 0X04H BIT DESCRIPTION
CHANNEL 0-7(0X04H-0X74H)
BIT
NAME
FUNCTION
D7
Reserved
D6
DMOIE
Digital Monitor Output Interrupt Enable
0 = Masks the DMO function
1 = Enables Interrupt Generation
R/W
0
D5
FLSIE
FIFO Limit Status Interrupt Enable
0 = Masks the FLS function
1 = Enables Interrupt Generation
R/W
0
D4
LCV/OFIE
Line Code Violation / Counter Overflow Interrupt Enable
0 = Masks the LCV/OF function
1 = Enables Interrupt Generation
R/W
0
D3
Reserved
This Register Bit is Not Used.
D2
AISIE
Alarm Indication Signal Interrupt Enable
0 = Masks the AIS function
1 = Enables Interrupt Generation
R/W
0
D1
RLOSIE
Receiver Loss of Signal Interrupt Enable
0 = Masks the RLOS function
1 = Enables Interrupt Generation
R/W
0
D0
QRPDIE
Quasi Random Signal Source Interrupt Enable
0 = Masks the QRPD function
1 = Enables Interrupt Generation
R/W
0
This Register Bit is Not Used.
59
XRT83VSH28
8-CHANNEL E1 SHORT-HAUL LINE INTERFACE UNIT
REV. 2.0.0
NOTE: The GIE bit in the global register 0xE0h must be set to "1" in addition to the individual register bits to enable the
interrupt pin.
TABLE 28: MICROPROCESSOR REGISTER 0X05H BIT DESCRIPTION
CHANNEL 0-7 (0X05H-0X75H)
FUNCTION
Register
Type
Default
Value
(HW reset)
BIT
NAME
D7
Reserved
D6
DMO
Digital Monitor Output
The digital monitor output is always active regardless if the interrupt generation is disabled. This bit indicates the DMO activity. An
interrupt will not occur unless the DMOIE is set to "1" in the channel register 0x04h and GIE is set to "1" in the global register
0xE0h.
0 = No Alarm
1 = Transmit output driver has failures
RO
0
D5
FLS
FIFO Limit Status
The FIFO limit status is always active regardless if the interrupt
generation is disabled. This bit indicates whether the RD/WR
pointers are within 3-Bits. An interrupt will not occur unless the
FLSIE is set to "1" in the channel register 0x04h and GIE is set to
"1" in the global register 0xE0h.
0 = No Alarm
1 = RD/WR FIFO pointers are within ±3-Bits
RO
0
D4
LCV/OF
Line Code Violation / Counter Overflow
This bit serves a dual purpose. By default, this bit monitors the line
code violation activity. However, if bit 7 in register 0x81h is set to a
"1", this bit monitors the overflow status of the internal LCV
counter. An interrupt will not occur unless the LCV/OFIE is set to
"1" in the channel register 0x04h and GIE is set to "1" in the global
register 0x80h.
0 = No Alarm
1 = A line code violation, bipolar violation, or excessive zeros has
occurred
RO
0
D3
Reserved
D2
AIS
RO
0
This Register Bit is Not Used.
This Register Bit is Not Used.
Alarm Indication Signal
The alarm indication signal detection is always active regardless if
the interrupt generation is disabled. This bit indicates the AIS
activity. An interrupt will not occur unless the AISIE is set to "1" in
the channel register 0x04h and GIE is set to "1" in the global register 0xE0h.
0 = No Alarm
1 = An all ones signal is detected
60
XRT83VSH28
8-CHANNEL E1 SHORT-HAUL LINE INTERFACE UNIT
REV. 2.0.0
NOTE: The GIE bit in the global register 0xE0h must be set to "1" in addition to the individual register bits to enable the
interrupt pin.
TABLE 28: MICROPROCESSOR REGISTER 0X05H BIT DESCRIPTION
CHANNEL 0-7 (0X05H-0X75H)
Register
Type
Default
Value
(HW reset)
BIT
NAME
FUNCTION
D1
RLOS
Receiver Loss of Signal
The receiver loss of signal detection is always active regardless if
the interrupt generation is disabled. This bit indicates the RLOS
activity. An interrupt will not occur unless the RLOSIE is set to "1"
in the channel register 0x04h and GIE is set to "1" in the global
register 0xE0h.
0 = No Alarm
1 = An RLOS condition is present
RO
0
D0
QRPD
Quasi Random Pattern Detection
The quasi random pattern detection is always active regardless if
the interrupt generation is disabled. This bit indicates that a QRPD
has been detected. An interrupt will not occur unless the QRPDIE
is set to "1" in the channel register 0x04h and GIE is set to "1" in
the global register 0xE0h.
0 = No Alarm
1 = A QRP is detected
RO
0
Register
Type
Default
Value
(HW reset)
TABLE 29: MICROPROCESSOR REGISTER 0X06H BIT DESCRIPTION
CHANNEL 0-7 (0X06H-0X76H)
BIT
NAME
FUNCTION
D7
Reserved
D6
DMOIS
Digital Monitor Output Status
0 = No change
1 = Change in status occurred
RUR
0
D5
FLSIS
FIFO Limit Status
0 = No change
1 = Change in status occurred
RUR
0
D4
LCV/OFIS
Line Code Violation / Overflow Status
0 = No change
1 = Change in status occurred
RUR
0
D3
Reserved
This Register Bit is Not Used.
D2
AISIS
RUR
0
This Register Bit is Not Used.
Alarm Indication Signal Status
0 = No change
1 = Change in status occurred
61
XRT83VSH28
8-CHANNEL E1 SHORT-HAUL LINE INTERFACE UNIT
REV. 2.0.0
TABLE 29: MICROPROCESSOR REGISTER 0X06H BIT DESCRIPTION
CHANNEL 0-7 (0X06H-0X76H)
BIT
NAME
D1
RLOSIS
D0
QRPDIS
Register
Type
Default
Value
(HW reset)
Receiver Loss of Signal Status
0 = No change
1 = Change in status occurred
RUR
0
Quasi Random Pattern Detection Status
0 = No change
1 = Change in status occurred
RUR
0
FUNCTION
NOTE: Any change in status will generate an interrupt (if enabled in channel register 0x04h and GIE is set to "1" in the
global register 0x80h). The status registers are reset upon read (RUR).
62
XRT83VSH28
8-CHANNEL E1 SHORT-HAUL LINE INTERFACE UNIT
5.9
REV. 2.0.0
Global Control Registers
TABLE 30: MICROPROCESSOR REGISTER 0X80H, BIT DESCRIPTION
REGISTER ADDRESS
0X80H
REGISTER
TYPE
RESET
VALUE
Single-rail/Dual-rail Select: Writing a “1” to this bit configures
all 4channels in the XRT83VSH28 to operate in the Single-rail
mode.
Writing a “0” configures the XRT83VSH28 to operate in Dualrail mode.
R/W
0
ATAOS
Automatic Transmit All Ones Upon RLOS: Writing a “1” to
this bit enables the automatic transmission of All "Ones" data
to the line for the channel that detects an RLOS condition.
Writing a “0” disables this feature.
R/W
0
D5
RCLKE
Receive Clock Edge: Writing a “1” to this bit selects receive
output data of all channels to be updated on the negative edge
of RCLK.
Wring a “0” selects data to be updated on the positive edge of
RCLK.
R/W
0
D4
TCLKE
Transmit Clock Edge: Writing a “0” to this bit selects transmit
data at TPOS_n/TDATA_n and TNEG_n/CODES_n of all
channels to be sampled on the falling edge of TCLK_n.
Writing a “1” selects the rising edge of the TCLK_n for sampling.
R/W
0
D3
DATAP
DATA Polarity: Writing a “0” to this bit selects transmit input
and receive output data of all channels to be active “High”.
Writing a “1” selects an active “Low” state.
R/W
0
D2
Reserved
D1
GIE
D0
SRESET
NAME
FUNCTION
D7
SR/DR
D6
BIT #
0
Global Interrupt Enable: Writing a “1” to this bit globally
enables interrupt generation for all channels.
Writing a “0” disables interrupt generation.
R/W
0
Software Reset P Registers: Writing a “1” to this bit longer
than 10µs initiates a device reset through the microprocessor
interface. All internal circuits are placed in the reset state with
this bit set to a “1” except the microprocessor register bits.
R/W
0
63
XRT83VSH28
8-CHANNEL E1 SHORT-HAUL LINE INTERFACE UNIT
REV. 2.0.0
TABLE 31: MICROPROCESSOR REGISTER 0X81H, BIT DESCRIPTION
REGISTER ADDRESS
0X81H
NAME
FUNCTION
REGISTER
TYPE
RESET
VALUE
BIT #
D7
Reserved
R/W
0
D6
Reserved
R/W
0
D5
Reserved
R/W
0
D4
Reserved
R/W
0
D3
Reserved
R/W
0
D2
RXMUTE
R/W
0
Receive Output Mute: Writing a “1” to this bit, mutes receive
outputs at RPOS/RDATA and RNEG/LCV pins to a “0” state for
any channel that detects an RLOS condition.
NOTE: RCLK is not muted.
D1
EXLOS
Extended LOS: Writing a “1” to this bit extends the number of
zeros at the receive input of each channel before RLOS is
declared to 4096 bits. Writing a “0” reverts to the normal mode
(32 bits for E1).
R/W
0
D0
ICT
In-Circuit-Testing: Writing a “1” to this bit configures all the
output pins of the chip in high impedance mode for In-CircuitTesting. Setting the ICT bit to “1” is equivalent to connecting
the Hardware ICT pin 88 to ground.
R/W
0
TABLE 32: MICROPROCESSOR REGISTER 0X82H BIT DESCRIPTION
GLOBAL REGISTER (0X82H)
BIT
D7
NAME
FUNCTION
TxONCNTL Transmit On Control
This register bit grants access to controlling the state of the transmitter outputs.
0 = Control comes from the TxON Register Bits
1 = Control comes from the TxON Hardware Pins
Register
Type
Default
Value
(HW reset)
R/W
0
D6
TERCNTL
Receive Termination Select Control
This bit sets the LIU to control the RxTSEL function with either the
individual channel register bit or the global hardware pin.
0 = Control of the receive termination is set to the register bits
1 = Control of the receive termination is set to the RxTSEL hardware pin
R/W
0
D[5:0]
Reserved
These Register Bits are Not Used
R/W
0
64
XRT83VSH28
8-CHANNEL E1 SHORT-HAUL LINE INTERFACE UNIT
REV. 2.0.0
TABLE 33: MICROPROCESSOR REGISTER 0X8CH BIT DESCRIPTION
GLOBAL REGISTER (0X8CH)
Register
Type
Default
Value
(HW reset)
This Register Bit is Not Used
R/W
0
Reserved
This Register Bit is Not Used
R/W
0
D5
Reserved
This Register Bit is Not Used
R/W
0
D4
Reserved
This Register Bit is Not Used
R/W
0
D3
D2
D1
D0
LCVCH3
LCVCH2
LCVCH1
LCVCH0
Line Code Violation Counter Select
These bits are used to select which channel is to be addressed for
reading the contents in register 0x8Eh. It is also used to address
the counter for a given channel when performing an update or
reset on a per channel basis. By default, Channel 0 is selected.
0000 = None
0001 = Channel 0
0010 = Channel 1
0011 = Channel 2
0100 = Channel 3
0100 = Channel 4
0100 = Channel 5
0100 = Channel 6
0100 = Channel 7
R/W
0
0
0
0
Register
Type
Default
Value
(HW reset)
BIT
NAME
D7
Reserved
D6
FUNCTION
TABLE 34: MICROPROCESSOR REGISTER 0X8DH BIT DESCRIPTION
GLOBAL REGISTER (0X8DH)
BIT
NAME
D7
Reserved
This Register Bit is Not Used
R/W
0
D6
Reserved
This Register Bit is Not Used
R/W
0
D5
Reserved
This Register Bit is Not Used
R/W
0
D4
allRST
LCV Counter Reset for All Channels
This bit is used to reset all internal LCV counters to their default
state 0000h. This bit must be set to "1" for 1S.
0 = Normal Operation
1 = Resets all Counters
R/W
0
allUPDATE LCV Counter Update for All Channels
This bit is used to latch the contents of all counters into holding
registers so that the value of each counter can be read. The channel is addressed by using bits D[3:0] in register 0x8Ch.
0 = Normal Operation
1 = Updates all Counters
R/W
0
D3
FUNCTION
65
XRT83VSH28
8-CHANNEL E1 SHORT-HAUL LINE INTERFACE UNIT
REV. 2.0.0
TABLE 34: MICROPROCESSOR REGISTER 0X8DH BIT DESCRIPTION
GLOBAL REGISTER (0X8DH)
Register
Type
Default
Value
(HW reset)
LCV Counter Byte Select
This bit is used to select the MSB or LSB for Reading the contents
of the LCV counter for a given channel. The channel is addressed
by using bits D[3:0] in register 0x8Ch. By default, the LSB byte is
selected.
0 = Low Byte
1 = High Byte
R/W
0
chUPDATE LCV Counter Update Per Channel
This bit is used to latch the contents of the counter for a given
channel into a holding register so that the value of the counter can
be read. The channel is addressed by using bits D[3:0] in register
0x8Ch.
0 = Normal Operation
1 = Updates the Selected Channel
R/W
0
R/W
0
Register
Type
Default
Value
(HW reset)
R/W
0
0
0
0
0
0
0
0
BIT
NAME
FUNCTION
D2
BYTEsel
D1
D0
chRESET
LCV Counter Reset Per Channel
This bit is used to reset the LCV counter of a given channel to its
default state 0000h. The channel is addressed by using bits D[3:0]
in register 0x8Ch. This bit must be set to "1" for 1S.
0 = Normal Operation
1 = Resets the Selected Channel
TABLE 35: MICROPROCESSOR REGISTER 0X8EH BIT DESCRIPTION
GLOBAL REGISTER (0X8EH)
BIT
NAME
FUNCTION
D7
D6
D5
D4
D3
D2
D1
D0
LCVCNT7
LCVCNT6
LCVCNT5
LCVCNT4
LCVCNT3
LCVCNT2
LCVCNT1
LCVCNT0
Line Code Violation Byte Contents
These bits contain the LCV counter contents of the Byte selected
by bit D2 in register 0x8Dh for a given channel. The channel is
addressed by using bits D[3:0] in register 0x8Ch. By default, the
contents contain the LSB, however no channel is selected..
66
XRT83VSH28
8-CHANNEL E1 SHORT-HAUL LINE INTERFACE UNIT
REV. 2.0.0
TABLE 36: MICROPROCESSOR REGISTER 0XFEH BIT DESCRIPTION
DEVICE "ID" REGISTER (0XFEH)
BIT
D7
D6
D5
D4
D3
D2
D1
D0
NAME
FUNCTION
Device "ID" The device "ID" of the XRT83VSH28 short haul LIU is 0xF1h.
Along with the revision "ID", the device "ID" is used to enable software to identify the silicon adding flexibility for system control and
debug.
Register
Type
Default
Value
(HW reset)
RO
1
1
1
1
0
0
0
1
Register
Type
Default
Value
(HW reset)
RO
0
0
0
0
0
0
1
1
TABLE 37: MICROPROCESSOR REGISTER 0XFFH BIT DESCRIPTION
REVISION "ID" REGISTER (0XFFH)
BIT
NAME
D7
D6
D5
D4
D3
D2
D1
D0
Revision
"ID"
FUNCTION
The revision "ID" of the XRT83VSH28 LIU is used to enable software to identify which revision of silicon is currently being tested.
The revision "ID" for the first revision of silicon will be 0x01h.
67
XRT83VSH28
8-CHANNEL E1 SHORT-HAUL LINE INTERFACE UNIT
REV. 2.0.0
6.0 ELECTRICAL CHARACTERISTICS
TABLE 38: ABSOLUTE MAXIMUM RATINGS
Storage Temperature
-65°C to +150°C
Operating Temperature
-40°C to +85°C
Supply Voltage
-0.5V to +3.8V
Vin
-0.5V to +5.5V
Maximum Junction Temperature
125°C
Theta JA
24°C/W
Theta JC
10°C/W
TABLE 39: DC DIGITAL INPUT AND OUTPUT ELECTRICAL CHARACTERISTICS
VDD=3.3V ±5%, TA=25°C, UNLESS OTHERWISE SPECIFIED
PARAMETER
SYMBOL
MIN
TYP
MAX
UNITS
VDD
3.13
3.3
3.46
V
Input High Voltage
VIH
2.0
-
5.0
V
Input Low Voltage
VIL
-0.5
-
0.8
V
Output High Voltage IOH=2.0mA
VOH
2.4
-
Output Low Voltage IOL=2.0mA
VOL
-
-
0.4
V
Input Leakage Current
IL
-
-
±10
µA
Input Capacitance
CI
-
5.0
Output Lead Capacitance
CL
-
-
Power Supply Voltage
V
pF
25
pF
NOTE: Input leakage current excludes pins that are internally pulled "Low" or "High"
TABLE 40: AC ELECTRICAL CHARACTERISTICS
VDD=3.3V ±5%, TA=25°C, UNLESS OTHERWISE SPECIFIED
PARAMETER
SYMBOL
MIN
TYP
MAX
UNITS
MCLKin Clock Duty Cycle
40
-
60
%
MCLKin Clock Tolerance
-
±50
-
ppm
68
XRT83VSH28
8-CHANNEL E1 SHORT-HAUL LINE INTERFACE UNIT
REV. 2.0.0
TABLE 41: POWER CONSUMPTION
VDD=3.3V ±5%, TA=25°C, UNLESS OTHERWISE SPECIFIED
MODE
SUPPLY
VOLTAGE
IMPEDANCE
RECEIVER
TRANSMITTER
TYP
MAX
UNIT
TEST
CONDITION
E1
3.3V
75
1:1
1:2
1.401
1.037
-
W
100% ones
50% ones
E1
3.3V
120
1:1
1:2
1.293
0.977
-
W
100% ones
50% ones
NOTE: The typical power consumption of the 1.8V supply represents ~ 36mW of the above listed.
TABLE 42: E1 RECEIVER ELECTRICAL CHARACTERISTICS
(VDD=3.3V±5%, TA=25°C UNLESS OTHERWISE SPECIFIED)
MIN
TYP.
MAX
UNIT
Number of consecutive
zeros before LOS is set
-
32
-
bit
Input signal level at LOS
13
16
-
dB
12.5
-
-
% ones
Receiver Sensitivity
9
-
-
dB
With nominal pulse amplitude of 3.0V for
120 and 2.37V for 75 application.
Interference Margin
-18
-14
-
dB
With 6dB cable loss
Input Impedance
15
-
K
Jitter Tolerance:
1 Hz
10KHz---100KHz
37
0.3
-
-
UIpp
UIpp
-
20
36
0.5
KHz
dB
-
10
1.5
-
Hz
Hz
12
8
8
-
-
dB
dB
dB
PARAMETER
TEST CONDITIONS
Receiver loss of signal:
RLOS Clear
Recovered Clock Jitter
Transfer Corner Frequency
Peaking Amplitude
Jitter Attenuator Corner
Frequency(-3dB curve)
JABW=0
JSBW=1
Return Loss:
51KHz --- 102KHz
102KHz --- 2048KHz
2048KHz --- 3072KHz
Cable attenuation @1024KHz
ITU-G.775, ETS1 300 233
ITU G.823
ITU G.736
ITU G.736
69
ITU G.703
XRT83VSH28
8-CHANNEL E1 SHORT-HAUL LINE INTERFACE UNIT
REV. 2.0.0
TABLE 43: E1 TRANSMITTER ELECTRICAL CHARACTERISTICS
VDD=3.3V ±5%, TA=25°C, UNLESS OTHERWISE SPECIFIED
PARAMETER
MIN
TYP
MAX
UNIT
AMI Output Pulse Amplitude
75
120
2.13
2.70
2.37
3.00
2.60
3.30
V
V
Output Pulse Width
224
244
264
ns
Output Pulse Width Ratio
0.95
-
1.05
ITU-G.703
Output Pulse Amplitude Ratio
0.95
-
1.05
ITU-G.703
-
0.025
0.05
UIp-p
15
9
8
-
-
dB
dB
dB
Jitter Added by the Transmitter
Output
Output Return Loss
51kHz - 102kHz
102kHz - 2048kHz
2048kHz - 3072kHz
70
TEST CONDITION
1:2 Transformer
Broad Band with jitter free TCLK
applied to the input.
ETSI 300 166
XRT83VSH28
8-CHANNEL E1 SHORT-HAUL LINE INTERFACE UNIT
REV. 2.0.0
PACKAGE DIMENSIONS
225 BALL PLASTIC BALL GRID ARRAY (BOTTOM VIEW)
(19.0 X 19.0 X 1.0mm)
18
16
17
14
15
12
13
10
11
8
9
6
7
4
5
2
3
A1
Feature / Mark
1
A
B
C
D
E
F
G
H
D
J
D1
K
L
M
N
P
R
T
U
V
D1
D
(A1 corner feature is mfger option)
D2
A2
Seating Plane
b
A
e
A1
Note: The control dimension is in millimeter.
INCHES
MILLIMETERS
SYMBOL
A
A1
A2
A3
D
D1
D2
b
e
MIN
MAX
0.049
0.096
0.016
0.024
0.013
0.024
0.020
0.048
0.740
0.756
0.669 BSC
0.665
0.669
0.020
0.028
0.039 BSC
71
MIN
MAX
1.24
2.45
0.40
0.60
0.32
0.60
0.52
1.22
18.80
19.20
17.00 BSC
16.90
17.00
0.50
0.70
1.00 BSC
A3
XRT83VSH28
8-CHANNEL E1 SHORT-HAUL LINE INTERFACE UNIT
REV. 2.0.0
ORDERING INFORMATION
PART NUMBER
PACKAGE
OPERATING TEMPERATURE RANGE
XRT83VSH28IB
225 Ball BGA
-40°C to +85°C
REVISIONS
REVISION #
DATE
DESCRIPTION
1.0.0
09/17/07
First release of the 8-channel E1 LIU Final Datasheet
2.0.0
03/01/10
Changed Device and Revision ID’s
NOTICE
EXAR Corporation reserves the right to make changes to the products contained in this publication in order to
improve design, performance or reliability. EXAR Corporation assumes no responsibility for the use of any
circuits described herein, conveys no license under any patent or other right, and makes no representation that
the circuits are free of patent infringement. Charts and schedules contained here in are only for illustration
purposes and may vary depending upon a user’s specific application. While the information in this publication
has been carefully checked; no responsibility, however, is assumed for inaccuracies.
EXAR Corporation does not recommend the use of any of its products in life support applications where the
failure or malfunction of the product can reasonably be expected to cause failure of the life support system or
to significantly affect its safety or effectiveness. Products are not authorized for use in such applications unless
EXAR Corporation receives, in writing, assurances to its satisfaction that: (a) the risk of injury or damage has
been minimized; (b) the user assumes all such risks; (c) potential liability of EXAR Corporation is adequately
protected under the circumstances.
Copyright 2010 EXAR Corporation
Datasheet March 2010.
Reproduction, in part or whole, without the prior written consent of EXAR Corporation is prohibited.
72