A product Line of
Diodes Incorporated
PI7C9X762
I2C-bus/SPI to UART Bridge Controller w/ 64 bytes of TX/RX FIFOs
Features
ÎÎDual channel full-duplex UART
SPI interface
ÎÎSupport I2C-bus or SPI interface
ÎÎPI7C9X762 supports 33 Mbit/s maximum SPI clock speed
ÎÎ64 bytes FIFO (transmitter and receiver)
ÎÎSupport SPI mode 0 (slave mode only)
ÎÎFully compatible with industrial standard 16C450 and
equivalent
Description
ÎÎBaud Rates up to 16Mbit/s in 4X sampling clock rate
The PI7C9X762 is a I2C-bus/SPI to a dual-channel high performance UART bridge controller. It offers data rates up to
33 Mbps and guarantees low operating and sleeping current.
The PI7C9X762 also has up to 8 additional programmable general purpose I/O [GPIO] pins. The device comes in very small
TSSOP28 packages, which makes it ideally suitable for cost efficient, handheld, battery operated applications. These UARTs
provide a bridge for protocol conversion from I2C -bus or SPI to
and RS-232/RS-485 and are fully bidirectional.
ÎÎProgrammable character formatting
àà 5-bit, 6-bit, 7-bit or 8-bit character
àà Even, odd, or no parity
àà 1, 1.5, or 2 stop bits
ÎÎProgrammable Receive and Transmit FIFO trigger levels
ÎÎSpecial character detection
ÎÎInternal Loopback mode
ÎÎLine break generation and detection
The PI7C9X762 supports SPI clock speeds up to 33 Mbps and
IrDA SIR up to 1.152 Mbit/s.
Flow control
ÎÎSupport hardware flow control using RTS/CTS
PI7C9X762’s internal register set is backward-compatible with the
widely used and widely popular 16C450 UART. The PI7C9X762
also provides additional advanced features such as auto hardware
and software flow control, automatic RS-485 support, support for
fractional baud rates and software reset. This allows the software
to reset the UART at any moment, independent of the hardware
reset signal.
ÎÎSupport software flow control with programmable Xon/Xoff
characters
ÎÎProgrammable single or double Xon/Xoff characters
Interface control
ÎÎAutomatic RS-485 slave address detection
ÎÎRS-485 driver direction control via RTS signal
ÎÎRS-485 driver direction control inversion
ÎÎBuilt-in IrDA encoder and decoder interface
Application
ÎÎSupports IrDA SIR with speeds up to 115.2 kbit/s ( optional
ÎÎIndustrial computing
1.152Mbps)
ÎÎAutomation
ÎÎUp to eight user programmable GPIO pins
ÎÎFactory process control
ÎÎSoftware reset
ÎÎMobile computing
Others
ÎÎEmbedded applications
ÎÎLow standby current at 3.3 V
ÎÎBattery operated devices
ÎÎWide operation voltage (1.8V, 2.5V or 3.3V)
ÎÎNetworking
ÎÎIndustrial temperature ranges -40 ˚C to 85 ˚C
ÎÎAvailable in TSSOP28 and TQFN32 Packages
I2C interface
ÎÎCompliant with I2C-bus fast speed
ÎÎSupport slave mode only
ÎÎCrystal oscillator (up to 24MHz) or external clock (up to
64MHz) input
PI7C9X762
Document Number DS40306 Rev 4-2
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PI7C9X762
Block Diagram
I2C-bus interface
I2C-bus interface
VDD
VDD
SC16IS750/760
SC16IS750/760
TX
RX
RTS
CTS
16C450
COMPATIBLE
REGISTER
SETS
RESET
SCL
SDL
A0
A1
IRQ
SCL
SDL
A0
A1
IRQ
I2C-bus
GPIO[3:0]
VDD
I2C/SPI
XTAL1 XTAL2
SPI interface
VDD
GPIO4/DSR
GPIO5/DTR
GPIO6/CD
GPIO7/RI
GPIO
REGISTER
VDD
I2C-bus
1KΩ(3.3 v)
1.5KΩ(2.5 v)
4
1KΩ(3.3 v)
1.5KΩ(2.5 v)
16C450
COMPATIBLE
REGISTER
SETS
RESET
VDD
I2C/SPI
XTAL1
VSS
TX
RX
RTS
CTS
XTAL2
VSS
002aab971
002aab014
SPI interface
VDD
VDD
SC16IS750/760
16C450
COMPATIBLE
REGISTER
SETS
RESET
SCLK
CS
SO
SI
IRQ
SCLK
CS
SO
SI
IRQ
4
GPIO[3:0]
GPIO
REGISTER
VDD
I2C/SPI
XTAL1
Document Number DS40306 Rev 4-2
XTAL2
VSS
16C450
COMPATIBLE
REGISTER
SETS
RESET
SPI
1KΩ(3.3 v)
1.5KΩ(2.5 v)
PI7C9X762
SC16IS740
TX
RX
RTS
CTS
TX
RX
RTS
CTS
SPI
1KΩ(3.3 v)
1.5KΩ(2.5 v)
GPIO4/DSR
GPIO5/DTR
GPIO6/CD
GPIO7/RI
VDD
I2C/SPI
XTAL1
002aab396
2
XTAL2
VSS
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Pin Configuration
GPIO6/CDA
GPIO5/DTRA
GPIO7/RIA
VDD
VSS
CTSA
RTSA
terminal 1
index area
TXA
32-Pin TQFN (SPI Interface)
GPIO6/CDA
GPIO5/DTRA
GPIO7/RIA
VDD
VSS
RTSA
CTSA
terminal 1
index area
TXA
32-Pin TQFN (I2C-Bus Interface)
32 31 30 29 28 27 26 25
RXA 1
24 GPIO4/DSRA
23 RXB
RESET 2
32 31 30 29 28 27 26 25
RXA 1
24 GPIO4/DSRA
RESET 2
23 RXB
XTAL1 3
22 TXB
XTAL1 3
22 TXB
XTAL2 4
21 VSS
XTAL2 4
21 VSS
19 GPIO2/CDB
18 GPIO1/DTRB
CS 7
SI 8
17 GPIO0/DSRB
9 10 11 12 13 14 15 16
RTSB
CTSB
IRQ
VDD
VSS
SO
SCLK
RTSB
CTSB
IRQ
VDD
VSS
SDA
NC
VSS
SPI 6
19 GPIO2/CDB
18
GPIO1/DTRB
A0 7
A1 8
17 GPIO0/DSRB
9 10 11 12 13 14 15 16
I2C 6
SCL
20 GPIO3/RIB
VDD 5
20 GPIO3/RIB
VDD 5
28-Pin TSSOP
RTSA
CTSA
TXA
RXA
1
2
3
4
RESET
XTAL1
XTAL2
VDD
2
I C/SPI
CS/A0
SI/A1
SO
SCL/SCLK
SDA
PI7C9X762
28
GPIO7/RIA
27
GPIO6/CDA
26
25
GPIO5/DTRA
GPIO4/DSRA
5
6
7
24
RXB
TXB
VSS
8
9
10
11
12
13
14
21
20
19
GPIO3/RIB
18
GPIO0/DSRB
RTSB
CTSB
IRQ
Document Number DS40306 Rev 4-2
23
22
17
16
15
GPIO2/CDB
GPIO1/DTRB
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Pin Description
Pin Name
28-TSSOP 32-TQFN
Pin#
Pin#
Type Description
I2C (SPI) INTERFACE
CS/A0
CTSA
10
2
7
31
I
SPI chip select or I2C-bus device address select A0. If SPI confguration is selected
by I2C/SPI Chip select pin (Schmitt-trigger active LOW). If I2C-BUS configuration is selected by I2C/SPI pin, this pin along with A1 pin allows user to change
the device's base address. To select the device address, please refer to table 9.
I
UART clear to send (active LOW), channel A. Alogic 0 (LOW) on the CTSA
pin indicates the modem or data set is ready to accept transmit data from the
PI7C9X762. Status can be tested by reading MSR(4). This pim only affects the
transmit and receive operations when Auto-CTS function is enabled via the
Enhanced Features Register EFR(7) for hardware flow control operation.
CTSB
16
15
I
UART clear to send (active LOW), channel B. Alogic 0 on the CTSB pin
indicates the modem or data set is ready to accept transmit data from the
PI7C9X762. Status can be tested by reading MSR(4). This pim only affects the
transmit and receive operations when Auto-CTS function is enabled via the
Enhanced Features Register EFR(7) for hardware flow control operation.
I2C/SPI
9
6
I
I2C-bus or SPI interface select. I2C-Bus interface is selected if this pin is at logic
HIGH. SPI interface is selected if this pin is at logic LOW.
O
Interrupt (open-drain, active LOW). Interrupt is enabled when interrupt sources
are enabled in the Interrupt Enable Register (IER). Interrupt conditions include:
change of state of the input pins, receiver errors, available receiver buffer data,
availble transmit buffer space, or when a modem status flag is detected. An extemal resistor (1 k-ohm for 3.3 V, 1.5 k-ohm for 2.5 V) must be connected between
this pin and VDD.
I
SPI data input pin or I2C-bus device address select A1. If SPI configuration is
selected by I2C/SPI pin, this is the SPI data input pin. If I2C-bus configuration is
selected by I2C/SPI pin, this pin, this along with the A0 pin allows user to change
the slave base address. To select the device address, p;ease refer to Table 9.
IRQ
SI/A1
15
11
14
8
SO
12
9
O
SPI data output pin. If SPI configuration is selected by I2C/SPI pin, this is a
3-stateable output pin. If I2C-bus sonfiguration is selected by the I2C/SPI pin,
this pin is undefined and must be left as not connected.
SCL/SCLK
13
10
I
I2C-bus or SPI input clock.
14
11
I/O
I2C-bus data input/output, open-drain if I2C-bus configuration is selected by
I2C/SPI pin. If SPI configuration is selected, this is not used and must be connected to VSS.
GPIO0/DSRB 18
17
I/O
Programmable I/O pin or modem DSRB
GPIO1/DTRB 19
18
I/O
Programmable I/O pin or modem DTRB
GPIO2/CDB
20
19
I/O
Programmable I/O pin or modem CDB
GPIO3/RIB
21
20
I/O
Programmable I/O pin or modem RIB
GPIO4/DSRA 25
24
I/O
Programmable I/O pin or modem DSRA
GPIO5/DTRA 26
25
I/O
Programmable I/O pin or modem DTRA
SDA
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Pin Description Cont.
Pin Name
28-TSSOP 32-TQFN
Pin#
Pin#
Type Description
GPIO6/CDA
27
26
I/O
Programmable I/O pin or modem CDA
GPIO7/RIA
28
27
I/O
Programmable I/O pin or modem RIA
RESET
5
2
I
Hardware reset (active LOW)
O
UART request to send (active LOW). A logic 0 on the RTSA pin indicates the
transmitter has data ready and waiting to send. Writing a logic 1 in the Modem
Control Register MCR[1] will set this pin to a logic 0, indicating data is available. After a reset this pin set to a logic 1. This pin only affects the transmit and
receive operations when Auto-RTS function is enabled via the Enhanced Feature
Register (EFR[6]) for hardware flow control operation.
RTSA
1
30
RTSB
17
16
O
UART request to send (active LOW). A logic 0 on the RTSB pin indicates the
transmitter has data ready and waiting to send. Writing a logic 1 in the Modem
Control Register MCR[1] will set this pin to a logic 0, indicating data is available. After a reset this pin set to a logic 1. This pin only affects the transmit and
receive operations when Auto-RTS function is enabled via the Enhanced Feature
Register (EFR[6]) for hardware flow control operation.
RXA
4
1
I
Channel A receiver input. During the local Loopback mode, the RXA input pin
is disabled and TXA data is connected to the UARTA RXA input internally.
RXB
24
23
I
Channel B receiver input. During the local Loopback mode, the RXB input pin is
disabled and TXB data is connected to the UARTA RXB input internally.
TXA
3
32
O
Channel A transmitter output. During the local Loopback mode, the TXA input
pin is disabled and TXA data is connected to the UARTA RXA input internally.
TXB
23
22
O
Channel B transmitter output. During the local Loopback mode, the TXB input
pin is disabled and TXB data is connected to the UARTA RXB input internally.
VDD
8
5, 13, 28
Power supply.
VSS
22
12, 21, 29
Ground
center pad
The certer pad on the back side of the QFN32 package is metallic aand should be
connected to ground on the printed-circuit board.
VSS
XTAL1
6
XTAL2
7
PI7C9X762
Document Number DS40306 Rev 4-2
3
I
Crystal input or external clock input. A crystal can be connected between
XTAL1 and XTAL2 to form an internal oscillator circuit (see Figure 11). Alternatively, an external clock can be connected to this pin.
4
O
Crystal output. (See also XTAL1.) XTAL2 is used as a crystal oscillator output.
5
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Functional Description
The UART will perform serial-to-I2C-bus conversion on data characters received from peripheral devices or modems, and I2C-busto-serial conversion on data characters transmitted by the host. The complete status of the UART can be read at any time during
functional operation by the host.
The UART can be placed in an alternate mode (FIFO mode) relieving the host of excessive software overhead by buffering received/
transmitted characters. Both the receiver and transmitter FIFOs can store up to 64 characters (including three additional bits of error
status per character for the receiver FIFO) and have selectable or programmable trigger levels.
The UART has selectable hardware flow control and software flow control. Hardware flow control significantly reduces software
overhead and increases system efficiency by automatically controlling serial data flow using the RTS output and CTS input signals.
Software flow control automatically controls data flow by using programmable Xon/Xoff characters.
The UART includes a programmable baud rate generator that can divide the timing reference clock input by a divisor between 1 and
(216 - 1).
1. Trigger levels
The UART provides independently selectable and programmable trigger levels for both receiver and transmitter interrupt generation.
After reset, both transmitter and receiver FIFOs are disabled and so, in effect, the trigger level is the default value of one character.
The selectable trigger levels are available via the FIFO Control Register (FCR). The programmable trigger levels are available via the
Trigger Level Register (TLR). If TLR bits are cleared, then selectable trigger level in FCR is used. If TLR bits are not cleared, then
programmable trigger level in TLR is used.
2. Hardware flow control
Hardware flow control is comprised of Auto-CTS and Auto-RTS (see Figure 1). Auto-CTS and Auto-RTS can be enabled/disabled
independently by programming EFR[7:6].
With Auto-CTS, CTS must be active before the UART can transmit data.
Auto-RTS only activates the RTS output when there is enough room in the FIFO to receive data and de-activates the RTS output when
the RX FIFO is sufficiently full. The halt and resume trigger levels in the Transmission Control Register (TCR) determine the levels at
which RTS is activated/deactivated. If TCR bits are cleared, then selectable trigger levels in FCR are used in place of TCR.
If both Auto-CTS and Auto-RTS are enabled, when RTS is connected to CTS, data transmission does not occur unless the receiver
FIFO has empty space. Thus, overrun errors are eliminated during hardware flow control. If not enabled, overrun errors occur if the
transmit data rate exceeds the receive FIFO servicing latency.
UART 1
UART 2
RX
SERIAL TO
PARALLEL
TX
PARALLEL
TO SERIAL
RX
FIFO
TX
FIFO
FLOW
CONTROL
RTS
CTS
PARALLEL
TO SERIAL
TX
RX
FLOW
CONTROL
SERIAL TO
PARALLEL
TX
FIFO
RX
FIFO
FLOW
CONTROL
CTS
RTS
FLOW
CONTROL
Figure 1. Auto flow control (Auto-RTS and Auto-CTS) example
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2.1 Auto-RTS
Figure 2 shows RTS functional timing. The receiver FIFO trigger levels used in Auto-RTS are stored in the TCR. RTS is active if the
RX FIFO level is below the halt trigger level in TCR[3:0]. When the receiver FIFO halt trigger level is reached, RTS is de-asserted.
The sending device (for example, another UART) may send an additional character after the trigger level is reached (assuming the
sending UART has another character to send) because it may not recognize the de-assertion of RTS until it has begun sending the additional character. RTS is automatically reasserted once the receiver FIFO reaches the resume trigger level programmed via TCR[7:4].
This re-assertion allows the sending device to resume transmission.
Start
RX
character
N
Stop
Start
character
N+1
Stop
1
2
Start
IRQ#
Receive
FIFO
Read
N
N+1
002aab040
(1) N = receiver FIFO trigger level.
(2) The two blocks in dashed lines cover the case where an additional character is sent.
Figure 2. RTS functional timing
2.2 Auto-CTS
Figure 3 shows CTS functional timing. The transmitter circuitry checks CTS before sending the next data character. When CTS is active, the transmitter sends the next character. To stop the transmitter from sending the following character, CTS must be de-asserted
before the middle of the last stop bit that is currently being sent. The Auto-CTS function reduces interrupts to the host system. When
flow control is enabled, CTS level changes do not trigger host interrupts because the device automatically controls its own transmitter.
Without Auto-CTS, the transmitter sends any data present in the transmit FIFO and a receiver overrun error may result.
TX
Start
character
N
Stop
Start
bit 0 to bit 7
Stop
CTS
002aab041
(1) When CTS is LOW, the transmitter keeps sending serial data out.
(2) When CTS goes HIGH before the middle of the last stop bit of the current character, the transmitter
finishes sending the current
character, but it does not send the next character.
(3) When CTS goes from HIGH to LOW, the transmitter begins sending data again.
Figure 3. CTS functional timing
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3 Software flow control
Software flow control is enabled through the Enhanced Features Register and the Modem Control Register. Different combinations
of software flow control can be enabled by setting different combinations of EFR[3:0]. Table 1 shows software flow control options.
Table 1. Software flow control options (EFR[3:0])
EFR[3]
EFR[2]
EFR[1]
EFR[0]
TX, RX software flow control
0
0
x
x
no transmit flow control
1
0
x
x
transmit Xon1, Xoff1
0
1
x
x
transmit Xon2, Xoff2
1
1
x
x
transmit Xon1 and Xon2, Xoff1 and Xoff2
x
x
0
0
no receive flow control
x
x
1
0
receiver compares Xon1, Xoff1
x
x
0
1
receiver compares Xon2, Xoff2
1
0
1
1
transmit Xon1, Xoff1
receiver compares Xon1 or Xon2, Xoff1 or Xoff2
0
1
1
1
transmit Xon2, Xoff2
receiver compares Xon1 or Xon2, Xoff1 or Xoff2
1
1
1
1
transmit Xon1 and Xon2, Xoff1 and Xoff2
receiver compares Xon1 and Xon2, Xoff1 and Xoff2
0
0
1
1
no transmit flow control
receiver compares Xon1 and Xon2, Xoff1 and Xoff2
There are two other enhanced features relating to software flow control:
• Xon Any function (MCR[5]): Receiving any character will resume operation after recognizing the Xoff character. It is possible that
an Xon1 character is recognized as an Xon Any character, which could cause an Xon2 character to be written to the RX FIFO.
• Special character (EFR[5]): Incoming data is compared to Xoff2. Detection of the special character sets the Xoff interrupt (IIR[4]) but
does not halt transmission. The Xoff interrupt is cleared by a read of the Interrupt Identification Register (IIR). The special character
is transferred to the RX FIFO.
3.1 Receive flow control
When software flow control operation is enabled, UART will compare incoming data with Xoff1/Xoff2 programmed characters (in
certain cases, Xoff1 and Xoff2 must be received sequentially). When the correct Xoff characters are received, transmission is halted after completing transmission of the current character. Xoff detection also sets IIR[4] (if enabled via IER[5]) and causes IRQ to go LOW.
To resume transmission, an Xon1/Xon2 character must be received (in certain cases Xon1 and Xon2 must be received sequentially).
When the correct Xon characters are received, IIR[4] is cleared, and the Xoff interrupt disappears.
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3.2 Transmit flow control
Xoff1/Xoff2 character is transmitted when the RX FIFO has passed the halt trigger level programmed in TCR[3:0], or the selectable
trigger level in FCR[7:6].
Xon1/Xon2 character is transmitted when the RX FIFO reaches the resume trigger level programmed in TCR[7:4], or falls below the
lower selectable trigger level in FCR[7:6].
The transmission of Xoff/Xon(s) follows the exact same protocol as transmission of an ordinary character from the FIFO. This means
that even if the word length is set to be 5, 6, or 7 bits, then the 5, 6, or 7 least significant bits of Xoff1/Xoff2, Xon1/Xon2 will be transmitted. (Note that the transmission of 5, 6, or 7 bits of a character is seldom done, but this functionality is included to maintain
compatibility with earlier designs.)
It is assumed that software flow control and hardware flow control will never be enabled simultaneously. Figure 4 shows an example
of software flow control.
RECEIVE FIFO
TRANSMIT FIFO
data
SERIAL-TO-PARALLEL
PARALLEL-TO-SERIAL
Xoff–Xon–Xoff
SERIAL-TO-PARALLEL
PARALLEL-TO-SERIAL
Xon1 WORD
Xon1 WORD
Xon2 WORD
Xon2 WORD
Xoff1 WORD
Xoff1 WORD
Xoff2 WORD
compare
programmed
Xon-Xoff
characters
Xoff2 WORD
Figure 4. Example of software flow control
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4. Hardware Reset, Power-On Reset (POR) and Software Reset
These three reset methods are identical and will reset the internal registers as indicated in Table 4.
Table 2 summarizes the state of register after reset.
Table 2. Register reset
Register
Reset state
Interrupt Enable Register
all bits cleared
Interrupt Identification Register
bit 0 is set; all other bits cleared
FIFO Control Register
all bits cleared
Line Control Register
reset to 0001 1101 (0x1D)
Modem Control Register
all bits cleared
Line Status Register
bit 5 and bit 6 set; all other bits cleared
Modem Status Register
bits 3:0 cleared; bits 7:4 input signals
Enhanced Features Register
all bits cleared
Receive Holding Register
pointer logic cleared
Transmit Holding Register
pointer logic cleared
Transmission Control Register
all bits cleared
Trigger Level Register
all bits cleared
Transmit FIFO level
reset to 0100 0000 (0x40)
Receive FIFO level
all bits cleared
I/O direction
all bits cleared
I/O interrupt enable
all bits cleared
I/O control
all bits cleared
Extra Features Control Register
all bits cleared
Remark: Registers DLL, DLH, SPR, XON1, XON2, XOFF1, XOFF2 are not reset by the top-level reset signal RESET, Software Reset, that is, they
hold their initialization values during reset.
Table 3 summarizes the state of output signals after reset.
Table 3. Output signals after reset
Signal
Reset state
TX
HIGH
RTS
HIGH
I/Os
inputs
IRQ
HIGH by external pull-up
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5 Interrupts
The UART has interrupt generation and prioritization (seven prioritized levels of interrupts) capability. The interrupt enable registers
(IER and IOIntEna) enable each of the seven types of interrupts and the IRQ signal in response to an interrupt generation. When an
interrupt is generated, the IIR indicates that an interrupt is pending and provides the type of interrupt through IIR[5:0]. Table 4 summarizes the interrupt control functions.
Table 4. Interrupt Source and Priority Level
IIR[5:0]
Priority level
Interrupt type
Interrupt source
00 0001
none
none
None
00 0110
1
receiver line status
Overrun Error (OE), Framing Error (FE), Parity Error (PE), or
Break Interrupt (BI) errors occur in characters in the RX FIFO
00 1100
2
RX time-out
Stale data in RX FIFO
00 0100
2
RHR interrupt
Receive data ready (FIFO disable) or RX FIFO above trigger
level (FIFO enable)
00 0010
3
THR interrupt
Transmit FIFO empty (FIFO disable) or TX FIFO passes above
trigger level (FIFO enable)
00 0000
4
modem status
Change of state of modem input pins
11 0000
5
I/O pins
Input pins change of state
01 0000
6
Xoff interrupt
Receive Xoff character(s)/special character
10 0000
7
CTS, RTS
RTS pin or CTS pin change state from active (LOW) to inactive
(HIGH)
It is important to note that for the framing error, parity error, and break conditions, Line Status Register bit 7 (LSR[7]) generates the
interrupt. LSR[7] is set when there is an error anywhere in the RX FIFO, and is cleared only when there are no more errors remaining
in the FIFO. LSR[4:2] always represent the error status for the received character at the top of the RX FIFO. Reading the RX FIFO
updates LSR[4:2] to the appropriate status for the new character at the top of the FIFO. If the RX FIFO is empty, then LSR[4:2] are all
zeros.
For the Xoff interrupt, if an Xoff flow character detection caused the interrupt, the interrupt is cleared by an Xon flow character detection. If a special character detection caused the interrupt, the interrupt is cleared by a read of the IIR.
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5.1 Interrupt mode operation
In Interrupt mode (if any bit of IER[3:0] is 1) the host is informed of the status of the receiver and transmitter by an interrupt signal,
IRQ. Therefore, it is not necessary to continuously poll the Line Status Register (LSR) to see if any interrupt needs to be serviced.
Figure 5 shows Interrupt mode operation.
IIR
read IIR
HOST
IRQ
IER
1
1
1
1
RHR
THR
Figure 5. Interrupt mode operation
5.2 Polled mode operation
In Polled mode (IER[3:0] = 0000) the status of the receiver and transmitter can be checked by polling the Line Status Register (LSR).
This mode is an alternative to the FIFO Interrupt mode of operation where the status of the receiver and transmitter is
automatically known by means of interrupts sent to the CPU. Figure 6 shows FIFO Polled mode operation.
LSR
read LSR
HOST
IER
0
THR
0
0
0
RHR
Figure 6. FIFO Polled mode operation
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6 Sleep mode
Sleep mode is an enhanced feature of the UART. It is enabled when EFR[4], the enhanced functions bit, is set and when IER[4] is set.
Sleep mode is entered when:
• The serial data input line, RX, is idle (see Section 7 “Break and time-out conditions”).
• The TX FIFO and TX shift register are empty.
• There are no interrupts pending except THR.
Remark: Sleep mode will not be entered if there is data in the RX FIFO.
In Sleep mode, the clock to the UART is stopped. Since most registers are clocked using these clocks, the power consumption is greatly
reduced. The UART will wake up when any change is detected on the RX line, when there is any change in the state of the
modem input pins, or if data is written to the TX FIFO.
Remark: Writing to the divisor latches DLL and DLH to set the baud clock must not be done during Sleep mode. Therefore, it is advisable to disable Sleep mode using IER[4] before writing to DLL or DLH.
7 Break and time-out conditions
When the UART receives a number of characters and these data are not enough to set off the receive interrupt (because they do not
reach the receive trigger level), the UART will generate a time-out interrupt instead, 4 character times after the last character is received. The time-out counter will be reset at the center of each stop bit received or each time the receive FIFO is read.
A break condition is detected when the RX pin is pulled LOW for a duration longer than the time it takes to send a complete character
plus start, stop and parity bits. A break condition can be sent by setting LCR[6], when this happens the TX pin will be pulled LOW
until LSR[6] is cleared by the software.
8 Programmable baud rate generator
The UART contains a programmable baud rate generator that takes any clock input and divides it by a divisor in the range between 1
and (216 - 1). An additional divide-by-4 prescaler is also available and can be selected by MCR[7], as shown in Figure 7. The formula
for the baud rate is:
XTAL1 crystal input frequency
)
prescaler
Baud rate =
divisor x sample rate
(
where:
prescaler = 1, when MCR[7] is set to logic 0 after reset (divide-by-1 clock selected)
prescaler = 4, when MCR[7] is set to logic 1 after reset (divide-by-4 clock selected).
Divisor = {DLH, DLL}
Sample rate = 16 - SCR + CPRN
Remark: The default value of prescaler after reset is divide-by-1.
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PRESCALER
LOGIC
(DIVIDE-BV-1)
XTAL1
XTAL2
INTERNAL
OSCILLATOR
LOGIC
MCR[7] = 0
BAUD RATE
GENERATOR
LOGIC
input clock
PRESCALER
LOGIC
(DIVIDE-BY-4)
reference
clock
internal
baud rate
clock for
transmitter
and receiver
MCR[7] = 1
Figure 7. Prescaler and baud rate generator block diagram
DLL and DLH must be written to in order to program the baud rate. DLL and DLH are the least significant and most significant byte
of the baud rate divisor. If DLL and DLH are both zero, the UART is effectively disabled, as no baud clock will be generated.
Remark: The programmable baud rate generator is provided to select both the transmit and receive clock rates.
Table 5 to 8 show the baud rate and divisor correlation for crystal with frequency 1.8432 MHz, 3.072 MHz, 14.74926 MHz, and
24MHz respectively.
Figure 8 shows the crystal clock circuit reference.
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Table 5. Baud rates using a 1.8432 MHz crystal
Desired baud rate (bit/s)
Divisor used to generate
16x clock
Sample rate
Percent error difference
between desired and actual
50
2304
16
0
75
1536
16
0
110
1047
16
0.026
134.5
857
16
0.058
150
768
16
0
300
384
16
0
600
192
16
0
1200
96
16
0
1800
64
16
0
2000
46
20
0.617
2400
48
16
0
3600
32
16
0
4800
24
16
0
7200
16
16
0
9600
12
16
0
19200
6
16
0
38400
3
16
0
56000
2
16
2.86
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Table 6. Baud rates using a 3.072 MHz crystal
Desired baud rate (bit/s)
Divisor used to generate
16x clock
Sample rate
Percent error difference
between desired and actual
50
2304
16
0
75
2560
16
0
110
1745
16
0.026
134.5
1428
16
0.034
150
1280
16
0
300
640
16
0
600
320
16
0
1200
160
16
0
1800
90
19
0.195
2000
96
16
0
2400
80
16
0
3600
45
19
0.195
4800
40
16
0
7200
25
17
0.392
9600
20
16
0
19200
10
16
0
38400
5
16
0
XTAL1
XTAL2
X1
1.8432 MHz
C1
22 pF
C2
33 pF
Figure 8. Crystal oscillator circuit reference
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Table 7. Baud rates using a 14.74926 MHz crystal
Desired baud rate (bit/s)
Divisor used to generate
16x clock
Sample rate
Percent error difference
between desired and actual
38400
24
16
0.025
56000
11
24
0.235
57600
16
16
0.025
115200
8
16
0.025
153600
6
16
0.025
921600
1
16
0.025
Table 8. Baud rates using a 24 MHz crystal
Desired baud rate (bit/s)
Divisor used to generate
16x clock
Sample rate
Percent error difference
between desired and actual
4800
250
20
0
7200
159
21
0.17
25000
48
20
0
38400
25
25
0
57600
22
19
0.32
115200
8
26
0.16
225000
6
18
1.2
400000
3
20
0
921600
1
26
0.16
1000000
1
24
0
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9. RS-485 features
9.1 Auto RS-485 RTS control
Normally the RTS pin is controlled by MCR bit 1, or if hardware flow control is enabled, the logic state of the RTS pin is controlled
by the hardware flow control circuitry. EFCR register bit 4 will take the precedence over the other two modes; once this bit is set, the
transmitter will control the state of the RTS pin. The transmitter automatically asserts the RTS pin (logic 0) once the host writes data
to the transmit FIFO, and de-asserts RTS pin (logic 1) once the last bit of the data has been transmitted.
To use the auto RS-485 RTS mode the software would have to disable the hardware flow control function.
9.2 RS-485 RTS output inversion
EFCR bit 5 reverses the polarity of the RTS pin if the UART is in auto RS-485 RTS mode. When the transmitter has data to be sent it
de-asserts the RTS pin (logic 1), and when the last bit of the data has been sent out the transmitter asserts the RTS pin (logic 0).
9.3 Auto RS-485
EFCR bit 0 is used to enable the RS-485 mode (multidrop or 9-bit mode). In this mode of operation, a ‘master’ station transmits an
address character followed by data characters for the addressed ‘slave’ stations. The slave stations examine the received data and interrupt the controller if the received character is an address character (parity bit = 1).
To use the auto RS-485 RTS mode the software would have to disable the hardware flow control function.
9.3.1 Normal multidrop mode
The 9-bit mode in EFCR (bit 0) is enabled, but not Special Character Detect (EFR bit 5). The receiver is set to Force Parity 0 (LCR[5:3]
= 111) in order to detect address bytes.
With the receiver initially disabled, it ignores all the data bytes (parity bit = 0) until an address byte is received (parity bit = 1). This
address byte will cause the UART to set the parity error. The UART will generate a line status interrupt (IER bit 2 must be set to ‘1’ at
this time), and at the same time puts this address byte in the RX FIFO. After the controller examines the byte it must make a decision
whether or not to enable the receiver; it should enable the receiver if the address byte addresses its ID address, and must not enable the
receiver if the address byte does not address its ID address.
If the controller enables the receiver, the receiver will receive the subsequent data until being disabled by the controller after the
controller has received a complete message from the ‘master’ station. If the controller does not disable the receiver after receiving a
message from the ‘master’ station, the receiver will generate a parity error upon receiving another address byte. The controller then
determines if the address byte addresses its ID address, if it is not, the controller then can disable the receiver. If the address byte addresses the ‘slave’ ID address, the controller take no further action; the receiver will receive the subsequent data.
9.3.2 Auto address detection
If Special Character Detect is enabled (EFR[5] is set and XOFF2 contains the address byte) the receiver will try to detect an address
byte that matches the programmed character in XOFF2. If the received byte is a data byte or an address byte that does not match the
programmed character in XOFF2, the receiver will discard these data. Upon receiving an address byte that matches the XOFF2 character, the receiver will be automatically enabled if not already enabled, and the address character is pushed into the RX FIFO along
with the parity bit (in place of the parity error bit). The receiver also generates a line status interrupt (IER bit 2 must be set to 1 at this
time). The receiver will then receive the subsequent data from the ‘master’ station until being disabled by the controller after having
received a message from the ‘master’ station.
If another address byte is received and this address byte does not match XOFF2 character, the receiver will be automatically disabled
and the address byte is ignored. If the address byte matches XOFF2 character, the receiver will put this byte in the RX FIFO along with
the parity bit in the parity error bit (LSR[2]).
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10. I2C-bus Interface
The I2C-bus interface is compliant with the Standard-mode and Fast-mode I2C-bus specifications. The I2C-bus interface consists of
two lines: serial data (SDA) and serial clock (SCL). In the Standard-mode, the serial clock and serial data can go up to 100 kbps and
in the Fast-mode, the serial clock and serial data can go up to 400 kbps. The first byte sent by an I2C-bus master contains a start bit
(SDA transition from HIGH to LOW when SCL is HIGH), 7-bit slave address and whether it is a read or write transaction. The next
byte is the sub-address that contains the address of the register to access. The UART responds to each write with an acknowledge
(SDA driven LOW by UART for one clock cycle when SCL is HIGH). If the TX FIFO is full, the UART will respond with a negative
acknowledge (SDA driven HIGH by UART for one clock cycle when SCL is HIGH) when the CPU tries to write to the TX FIFO.
The last byte sent by an I2C-bus master is a stop bit (SDA transition from LOW to HIGH when SCL is HIGH). See Figures 8 - 10 below.
For complete details, see the I2C-bus specifications.
SDA
SCL
S
P
START condition
STOP condition
Figure 9. I2C Start and Stop Conditions
SLAVE
ADDRESS
S
W
REGISTER
ADRESS
A
A
nDATA
A
P
White block: host to UART
Grey block: UART to host
Figure 10. Master writes to slave (UART)
S
SLAVE
ADDRESS
W
A
REGISTER
ADRESS
A
S
SLAVE
ADDRESS
R
A
nDATA
A
LAST DATA
NA
P
White block: host to UART
Grey block: UART to host
Figure 11. Master reads from slave (UART)
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Data transferred (n bytes + acknowledge)
Master write:
S
SLAVE
ADDRESS
START condition
W
A
DATA
DATA
A
acknowledge
write acknowledge
A
P
acknowledge STOP condition
Data transferred (n bytes + acknowledge)
Master read:
S
SLAVE
ADDRESS
START condition
R
A
DATA
read acknowledge
DATA
A
acknowledge
NA
P
acknowledge STOP condition
Data transferred (n bytes
+ acknowledge)
Combined
formats:
S
SLAVE
ADDRESS
START condition
R/W
A
DATA
Read or acknowledge
write
A
Sr
Data transferred (n bytes
+ acknowledge)
SLAVE
ADDRESS
acknowledge Repeated
START condition
R/W
A
DATA
Read or acknowledge
write
A
P
acknowledge STOP condition
Direction of transfer may
change at this point
Figure 12. I2C data formats
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10.1 I2C-bus Addressing
There could be many devices on the I2C-bus. To distinguish itself from the other devices on the I2C-bus, there are eight possible slave
addresses that can be selected for the UART using the A1 and A0 address lines. Table 9 below shows the different addresses that can
be selected. Note that there are two different ways to select each I2C address.
Table 9: I2C Address Map
I2C ADDRESS
A1
A0
VDD
VDD
0x90 (1001 000X)
VDD
VSS
0x92 (1001 001X)
VDD
SCL
0x94 (1001 010X)
VDD
SDA
0x96 (1001 011X)
VSS
VDD
0x98 (1001 100X)
VSS
VSS
0x9A (1001 101X)
VSS
SCL
0x9C (1001 110X)
VSS
SDA
0x9E (1001 111X)
SCL
VDD
0xA0 (1010 000X)
SCL
VSS
0xA2 (1010 001X)
SCL
SCL
0xA4 (1010 010X)
SCL
SDA
0xA6 (1010 011X)
SDA
VDD
0xA8 (1010 100X)
SDA
VSS
0xAA (1010 101X)
SDA
SCL
0xAC (1010 110X)
SDA
SDA
0xAE (1010 111X)
An I2C sub-address is sent by the I2C master following the slave address. The sub-address contains the UART register address being
accessed. A read or write transaction is determined by bit-0 of the slave address (HIGH = Read, LOW = Write). Table 10 below lists
the functions of the bits in the I2C sub-address.
Table 10: I2C Sub-Address (Register Address)
Bit
Function
7
Reserved
6:3
UART Internal Register Address A3:A0
2:1
UART Channel Select
’00’ = UART Channel A
’01’ = UART Channel B
other values are reserved
0
Reserved
After the last read or write transaction, the I2C-bus master will set the SCL signal back to its idle state (HIGH).
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11. SPI Bus Interface
The SPI interface consists of four lines: serial clock (SCL), chip select (CS#), slave output (SO) and slave input (SI). The serial clock,
slave output and slave input can be as fast as 33 MHz at 3.3V. To access the device in the SPI mode, the CS# signal for the UART is
asserted by the SPI master, then the SPI master starts toggling the SCL signal with the appropriate transaction information. The first
bit sent by the SPI master includes whether it is a read or write transaction and the UART register being accessed. See Table 11 below.
Table 11: SPI First Byte Format
Bit
Function
7
Read/Write#
Logic 1 = Read
Logic 0 = Write
6:3
UART Internal Register Address A3:A0
2:1
UART Channel Select
’00’ = UART Channel A
’01’ = UART Channel B
Other values are reserved
0
Reserved
SCLK
SI
R/W
A3
A2
A1
0
A0
CH
X
D7
D6
D5
D4
D3
D3
D2
D2
D1
D0
Figure 13. SPI write
SCLK
SI
R/W
A3
SO
A2
A1
A0
0
CH
X
D7
D6
D5
D4
D1
D0
Figure 14. SPI read
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The 64 byte TX FIFO can be loaded with data or 64 byte RX FIFO data can be unloaded in one SPI write or read sequence.
SCLK
SO
R/W
A3
A2
A1
A0
0
CH
X
D7
D6
D5
D4
D3
D2
D1
D0
D7
D6
D5
D4
D3
D2
D1
D0
last bit
Figure 15. SPI FIFO write
SCLK
R/W
A3
A2
A1
A0
0
CH
X
D7
D6
D5
D4
D3
D2
D1
D0
D7
D6
D5
D4
D3
D2
D1
D0
last bit
Figure 16. SPI FIFO read
After the last read or write transaction, the SPI master will set the SCL signal back to its idle state (LOW).
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12 Infrared Mode
The UART includes the infrared encoder and decoder compatible to the IrDA (Infrared Data Association) version 1.0 and 1.1.
The IrDA 1.0 standard that stipulates the infrared encoder sends out a 3/16 of a bit wide HIGH-pulse for each “0” bit in the transmit
data stream with a data rate up to 115.2 Kbps. For the IrDA 1.1 standard, the infrared encoder sends out a 1/4 of a bit time wide HIGHpulse for each "0" bit in the transmit data stream with a data rate up to 1.152 Mbps. This signal encoding reduces the on-time of the
infrared LED, hence reduces the power consumption. See Figure 17 below.
The infrared encoder and decoder are enabled by setting MCR register bit-6 to a ‘1’. With this bit enabled, the infrared encoder and
decoder is compatible to the IrDA 1.0 standard. For the infrared encoder and decoder to be compatible to the IrDA 1.1 standard, EFCR
bit-7 will also need to be set to a ’1’. When the infrared feature is enabled, the transmit data output, TX, idles LOW. Likewise, the RX
input also idles LOW, see Figure 17.
The wireless infrared decoder receives the input pulse from the infrared sensing diode on the RX pin. Each time it senses a light
pulse, it returns a logic 1 to the data bit stream.
The UART can be in the infrared mode upon power-up if the ENIR# pin is LOW. After power-up, the infrared mode can be controlled
via MCR bit-6.
Character
Start
0
Data Bits
1
0
1
0
Stop
1
0
1
0
Tx Data
Transmit
IR Pulse
(TX Pin)
1/2 Bit Time
3/16 or 1/4
Bit Time
Bit Time
Receive
IR Pulse
(RX Pin)
IrEncoder-1
Bit Time
1/16 Clock Delay
0
1
0
1
0
0
1
1
0
1
RX Data
Start
Data Bits
Stop
Character
IRdecoder-1
Figure 17. Infrared transmit data receive data deconding
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Configuration Registers
Offset 00H: Receiver Holding Register (RHR). Accessable when LCR[7]=0. Default=00
Bit
Type
Description
[7:0]
RO
Rx Holding - When data are read from the RHR,they are removed from the top of the receiver's FIFO.
Data read from the RHR when FIFO is empty are invalid. The Line Status Register(LSR) indicates the
full or empty status of the FIFOs.
Offset 00H: Transmitter Holding Register (THR). Accessable when LCR[7]=0. Default=00
Bit
Type
Description
[7:0]
WO
Tx Holding - When data are written to the THR,they are written to the bottom of the transmitter's
FIFO. Data written to the THR when FIFO is full are lost. The Line Status Register(LSR) indicates the
full or empty status of the FIFOs.
Offset 00H: Divisor Latch LSB(DLL). Accessable when LCR[7]=1 and LCR!=0xBF. Default=01
Bit
Type
[7:0]
WO
Description
LSB bits of divisor for baud rate generator.
Note: It is reset only when Power-On-Reset.
Offset 01H: Interrupt Enable Register (IER). Accessable when LCR[7]=0. Default=00
Bit
Type
Description
7
RW
CTS interrupt - "1": Enable CTS/DSR interrupt
6
RW
RTS interrupt - "1": Enable RTS/DTR interrupt
5
RW
Xoff/Special charatcter interrupt - "1": Enable the Software Flow Control interrupt
RW
Sleep mode - "1" : Enable sleep mode (It requires EFR[4] = 1). The Uart may enter sleep mode when all
conditions met:
- no interrupts pending
- modem inputs are not toggled
- RX input pin is idling HIGH
- TX/RX FIFO are empty
4
It will exit from sleep mode when any below condition met:
- modem inputs are toggling
- RX input pin changed to LOW
-a data byte is loaded to the TX FIFO
In sleep mode, Crystal is stopped and no Uart clock
3
RW
Modem Status interrupt - "1": Enable Modem Status interrupt
2
RW
Receiver Line Status interrupt - "1": Enable Receiver Line Status interrupt
1
RW
1 = Interrupt is issued whenever the THR becomes empty in non-FIFO mode or when spaces in the
FIFO is above the trigger level in the FIFO mode.
0
RW
Rx Data Ready interrupt - "1": enable Data Ready interrupt
Tx Ready interrupt - "1": Enable THR Ready interrupt
Note: IER[7:4] can only be modified if EFR[4]=1.
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Configuration Registers cont.
Offset 01H: Divisor Latch MSB(DLH). Accessable when LCR[7]=1 and LCR!=0xBF. Default=00
Bit
Type
[7:0]
RW
Description
MSB bits of divisor for baud rate generator.
Note: It is reset only when Power-On-Reset.
Offset 02H: Interrupt Identification Register (IIR). Accessable when LCR[7]=0. Default=01
Bit
Type
Description
[7:6]
RO
Mirror the content of FCR[0]
[5:1]
RO
5-bit encoded interrupt.
0
RO
Interrupt status. "1": No interrupt is pending.
"0": An interrupt is pending.
Priority Level
IIR[5]
IIR[4]
IIR[3]
IIR[2]
IIR[1]
IIR[0]
Source of Interrupt
1
0
0
0
1
1
0
Receive Line Status Error
2
0
0
1
1
0
0
Receiver timeout
2
0
0
0
1
0
0
RHR interrupt
3
0
0
0
0
1
0
THR interrupt
4
0
0
0
0
0
0
Modem interrupt
5
1
1
0
0
0
0
Input pin change of state
6
0
1
0
0
0
0
Rx Xoff signal/special character
7
1
0
0
0
0
0
CTS,RTS change from active to inactiove
Note: IIR[4] is cleared by Xon detection if the interrupt is caused by Xoff detection, or cleared by a read of the IIR if it is caused by special char detection.
Offset 02H: FIFO Control Register (FCR). Accessable when LCR[7]=0. Default=00
Bit
Type
Description
WO
RX trigger. Sets the trigger level for the RX FIFO
00 = 8 characters
01 = 16 characters
10 = 56 characters
11 = 60 characters
[5:4]
WO
TX trigger. Sets the trigger level for the TX FIFO
00 = 8 spaces
01 = 16 spaces
10 = 32 spaces
11 = 56 spaces
3
RO
Reserved
WOS
Reset TX FIFO.
0 = No FIFO transmit reset
1 = Clears the contents of Tx FIFO and resets the FIFO level logic.
TSR is not cleared. This bit will return to logic 0 after clearing the FIFO
WOS
Reset RX FIFO.
0 = No FIFO receive reset
1 = Clears the contents of Rx FIFO and resets the FIFO level logic.
RSR is not cleared. This bit will return to logic 0 after clearing the FIFO
[7:6]
2
1
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Configuration Registers cont.
0
WO
FIFO enable
0 = Disable the transmit and receive FIFO, and TX/RX can only hold one character at a time. Other
FCR bits are not programmable, and the trigger level is set to one character.
1 = enable the transmit and receive FIFO. and TX/RX FIFO can hold 64 characters.
Note: FCR[5:4] can only be modified and enabled if EFR[4]=1.
Offset 02H: Enhanced Feature Register (EFR). Accessable when LCR=0xBF and SFR[2]=0. Default=00
Bit
Type
Description
7
RW
Auto CTS Flow Control Enable
0 = Automatic CTS flow control is disabled.
1 = Automatic CTS flow control is enabled.
6
RW
Auto RTS Flow Control Enable
0 = Automatic RTS flow control is disabled.
1 = Automatic RTS flow control is enabled.
5
RW
Special character detect
0 = Special character detect is disabled.
1 = Special character detect is enabled. If received data matchs Xoff2 data, the received data is transferred to RX FIFO and IIR[4] is set to high to indicate a special character detection.
However,if flow control is set for comparing Xoff2, then flow control works normally and Xoff2 will
not go to the FIFO and will generate an Xoff interrupt and a special character interrupt.
4
RW
Enhanced Function Bits Enable
This bit enables IER[7:4],IIR[5:4],FCR[5:4],MCR[7:5],TCR and TLP to be modified, and enables the
sleep mode.
[3:0]
RW
Software Flow Control Select:
00xx = No TX flow control
10xx = Transmit Xon1,Xoff1
01xx = Transmit Xon2,Xoff2
11xx = Transmit Xon1 and Xon2,Xoff1 and Xoff2
xx00 = No RX flow control
xx10 = Receiver compares Xon1,Xoff1
xx01 = Receiver compares Xon2,Xoff2
1011 = Transmit Xon1,Xoff1;
Receiver compares Xon1 or Xon2,Xoff1 or Xoff2
0111 = Transmit Xon2,Xoff2;
Receiver compares Xon1 or Xon2,Xoff1 or Xoff2
1111 = Transmit Xon1 and Xon2,Xoff1 and Xoff2;
Receiver compares Xon1 and Xon2,Xoff1 and Xoff2
0011 = No transmit flow control;
Receiver compares Xon1 and Xon2,Xoff1 and Xoff2
Offset 03H: Line Control Register (LCR). Default=1D
Bit
Type
Description
7
RW
Divisor latch enabled when set
6
RW
Break control bit.
0 = no TX break condition
1 = forces TX to logic 0 to alert a line break condition
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Configuration Registers cont.
5
RW
Set forced parity format(if LCR[3]=1)
0 = parity is not forced.
1 = parity bit is forced to high if LCR[4]=0,or low if LCR[4]=1.
4
RW
Parity type select.
0 = odd parity is generated(if LCR[3]=1)
1 = even parity is generated(if LCR[3]=1)
3
RW
Parity enable when set
2
RW
Number of Stop bits
0 = 1 stop bit.
1 = 1.5 stop bits for word length=5, or 2 stop bits for word length=6,7,8
RW
Word length bits:
00 = 5 bits. 01 = 6 bits
10 = 7 bits. 11 = 8 bits
1:0
Offset 04H: Modem Control Register (MCR). Accessable when LCR[7]=0. Default=00
Bit
Type
Description
7
RW
Clock pre-scaler select.
0 = divide-by-1 clock input
1 = divide-by-4 clock input
6
RW
IrDA mode enable when set.
5
RW
When set, Xon Any function is enabled and receiving any character will resume transmit operation.
the RX character will be loaded into the RX FIFO. unless the RX character is an Xon/Xoff character
and receiver software flow control is enabled.
4
RW
When set, internal loopback mode is enabled and TX output is looped back to the RX input internally,
and MCR[1:0] signals are looped back into MSR[4:5]
3
RW
OP2. It is not available as an output pin but can be controlled in Internal Loopback Mode(MCR[4]=1)
and is outputed to DCD internally.
2
RW
OP1/TCR and TLR enable. In Internal Loopback Mode(MCR[4]=1), it is outputed to RI internally.
otherwise it is used to select between the MSR and TCR registers at offset 0x6 and the SPR and TLR
registers at offset 0x7.
1
RW
RTS pin control.
0 = force RTS pin High
1 = force RTS pin Low
When IN internal loopback mode, it controls MSR[4].
If Auto-RTS is enabled, the RTS pin is controlled by hardware flow control .
0
RW
DTR pin control if GPIO5 or GPIO1 is selected as DTR modem pin through IOControl register bit 1
or bit 2:
0 = force DTR pin High
1 = force DTR pin Low
When internal loopback mode, it controls MSR[5].
Note: MCR[7:5],MCR[3:2] can only be modified if EFR[4]=1.
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Configuration Registers cont.
Offset 04H: XON1 character Register (XON1). Accessable when LCR=0xBF and SFR[2]=0. Default=00
Bit
Type
[7:0]
RW
Description
XON1 character
Note: It is reset only when Power-On-Reset.
Offset 05H: Line Status Register (LSR). Accessable when LCR[7]=0. Default=60
Bit
Type
Description
7
RO
Receiver FIFO Data Error Flag.
0 = No FIFO Error
1 = a flag for the sum of all error bits (parity error, framing error, or break) in the RX FIFO. this bit
clears when there is no more error in any of the bytes in the RX FIFO.
6
RO
THR and TSR Empty Flag
This bit is set whenever the transmitter goes idle, it clears whenever either the THR or TSR contains a
data character.
5
RO
THR Empty Flag
This bit is set when the last data byte is transferred from THR to TSR.
RO
Receiver Break Error Flag
0 = No Break Error
1 = break condition occurred in data to be read from RX FIFO(RX was LOW for at least one character
frame time).
3
RO
Receiver Data Framing Error Flag
0 = No Data Framing Error
1 = framing error occurred in data to be read from RX FIFO (The receive character did not have a
valid stop bits).
2
RO
Receiver Data Parity Error Flag
0 = No Data Parity Error
1 = parity error in data to be read from RX FIFO
1
RO
Receiver Overrun Error
0 = No verrun Error
1 = additional data received while the RX FIFO is full. This data should not be transferred into FIFO.
0
RO
Receiver Data Ready Indicator
0 = No data in received in RX FIFO
1 = Data has been received and saved in the RX FIFO
4
Offset 05H: XON2 character Register (XON2). Accessable when LCR=0xBF and SFR[2]=0. Default=00
Bit
Type
[7:0]
RW
Description
XON2 character
Note: It is reset only when Power-On-Reset.
Offset 06H: Modem Status Register (MSR). Accessable when LCR[7]=0 and MCR[2]=0 and SFR[2]=0. Default=00
Bit
Type
Description
CD input satus
7
RO
Normally this bit is the complement of the CD# input.
In the loopback mode this bit is equivalent to MCR[3].
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Configuration Registers cont.
RI input satus
6
RO
Normally this bit is the complement of the RI# input.
In the loopback mode this bit is equivalent to MCR[2].
DSR input satus
5
RO
Normally this bit is the complement of the DSR# input.
In the loopback mode this bit is equivalent to MCR[0].
CTS input satus
4
RO
Normally this bit is the complement of the CTS# input.
In the loopback mode this bit is equivalent to MCR[1].
3
2
1
0
RO
Delta CD# input flag
0 = No change on CD# input
1 = The CD# input has changed state. A modem status interrupt will be generated if MSR interrupt is
enabled.
RO
Delta RI# input flag
0 = No change on RI# input
1 = The RI# input has changed from a LOW to HIGH. A modem status interrupt will be generated if
MSR interrupt is enabled.
RO
Delta DSR# input flag
0 = No change on DSR# input
1 = The DSR# input has changed state. A modem status interrupt will be generated if MSR interrupt is
enabled.
RO
Delta CTS# input flag
0 = No change on CTS# input
1 = The CTS# input has changed state. A modem status interrupt will be generated if MSR interrupt is
enabled.
Offset 06H: Transmission Control Register (TCR). Accessable when EFR[4]=1 and MCR[2]=1 and SFR[2]=0. Default=00
Bit
Type
Description
RX FIFO Resume level.
[7:4]
RW
When the RX FIFO is less than or equal to the value (decimal value of TCR[7:4] multiplied by 4), the
RTS# output will be re-asserted if Auto RTS flow is used or XON character will be transmitted if Auto
XON/XOFF flow control is used. It is recommended that this value is less than the RX Trigger Level.
RX FIFO Halt level.
[3:0]
RW
When the RX FIFO is greater than or equal to the value (decimal value of TCR[3:0] multiplied by 4),
the RTS# output will be de-asserted if Auto RTS flow is used or XOFF character will be transmitted if
Auto XON/XOFF flow control is used. It is recommended that this value is greater than the RX Trigger Level.
Offset 06H: XOFF1 character Register (XOFF1). Accessable when LCR=0xBF and SFR[2]=0. Default=00
Bit
Type
[7:0]
RW
PI7C9X762
Document Number DS40306 Rev 4-2
Description
XOFF1 character
Note: It is reset only when Power-On-Reset.
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Configuration Registers cont.
Offset 07H: Scratch Pad Register (SPR). Accessable when LCR[7]=0 and MCR[2]=0. Default=FF
Bit
[7:0]
Type
Description
RW
This is 8-bit general purpose register for the user to store temporary data. the content is preserved
during sleep mode.
Note: It is reset only when Power-On-Reset.
Offset 07H: Trigger Level Register (TLR). Accessable when EFR[4]=1 and MCR[2]=1. Default=00
Bit
Type
Description
RX FIFO Trigger level.
[7:4]
RW
When the number of characters received in RX FIFO is greater than or equal to the value (decimal
value of TLR[7:4] multiplied by 4), a Receive Data Ready interrupt is generated. If TLR[7:4]=0x0, then
the RX FIFO Trigger Level is the value selected by FCR[7:6]
TX FIFO Trigger level.
[3:0]
RW
When the number of available space in TX FIFO is greater than or equal to the value (decimal value
of TLR[3:0] multiplied by 4), a Transmit Ready interrupt is generated. If TLR[3:0]=0x0, then the TX
FIFO Trigger Level is the value selected by FCR[5:4]
Offset 07H: XOFF2 character Register (XOFF2). Accessable when LCR=0xBF and SFREN!=0x5A. Default=00
Bit
Type
[7:0]
RW
Description
XOFF2 character
Note: It is reset only when Power-On-Reset.
Offset 08H: Transmit FIFO Level Register (TXLVL). Accessable when SFR[2]=0. Default=40
Bit
Type
Description
[7:0]
RO
This register reports the number of spaces available in the TX FIFO.
Offset 09H: Receiver FIFO Level Register (RXLVL). Accessable when SFR[2]=0. Default=00
Bit
Type
Description
[7:0]
RO
This register reports the number of character available in the RX FIFO.
Offset 0AH: GPIO Direction Register (IODir). Default=00
Bit
Type
Description
[7:0]
RW
This register program the direction of the GPIO pins.
0 = set GPIO pin as input
1 = set GPIO pin as output
Offset 0BH: GPIO State Register (IOState). Default=FF
Bit
[7:0]
PI7C9X762
Type
Description
RW
This register reports the state of all GPIO pins during read and writes to any GPIO that is an output
0 = set output pin LOW
1 = set output pin HIGH
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Configuration Registers cont.
Offset 0CH: GPIO Interrupt Enable Register (IOIntEna). Default=00
Bit
[7:0]
Type
Description
RW
This register enable the interrupt for GPIO pins. If GPIO[7:4] or GPIO[3:0] are programmed as modem pins, IOIntEna will have no effect on GPIO[7:4] or GPIO[3:0].
0 = disabled
1 = enabled
Offset 0EH: GPIO Control Register (IOControl). Default=00
Bit
Type
Description
[7:4]
RO
Reserved
Uart Software Reset.
3
RW
Writing a logic 1 to this bit will reset the device.
This bit is automatically be reset after device is reset.
2
RW
GPIO[3:0] or Modem IO Select(CH B)
0 = GPIO[3:0] behave as GPIO pins
1 = GPIO[3:0] behave as RIB#,CDB#,DTRB#,DSRB#
1
RW
GPIO[7:4] or Modem IO Select(CH A)
0 = GPIO[7:4] behave as GPIO pins
1 = GPIO[7:4] behave as RIA#,CDA#,DTRA#,DSRA#
RW
This bit enable GPIO inputs latching
0 = GPIO input values are not latched. If the input goes back to its initial logic state before the input
register is read, then the interrupt is cleared.
1 = GPIO input values are latched. If the input goes back to its initial logic state before the input register is read, then the interrupt is not cleared and the corresponding bit of IOState register keeps the
logic value that generated the interrupt.
0
Offset 0FH: Extra Features Control Register (EFCR). Accessable when SFR[2]=0, Default=00
Bit
Type
Description
7
RW
IrDA mode.
0 = IrDA version 1.0, 3/16 pulse ratio,data rate up to 115.2 Kbps
1 = IrDA version 1.1, 1/4 pulse ratio,data rate up to 1.152 Mbps
6
RO
Reserved
Auto RS-485 Polarity Inversion
5
RW
This bit changes the polarity of the Auto RS-485 Direction Control output(RTS#). it will only affect
the behavior of RTS# if EFCR[4]=1
0 = RTS# output is LOW when transmitting and HIGH when receiving
1 = RTS# output is HIGH when transmitting and LOW when receiving
Auto RS-485 direction control
4
RW
This bit enables the transmitter to control RTS# pin
0 = transmitter does not control RTS# pin
1 = transmitter controls RTS# pin
3
RO
Reserved
Notes: GPIO registers(0AH-0EH) are channel independent. For example, setting software reset will reset all channels.
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Configuration Registers cont.
2
RW
Transmitter Disable
0 = transmitter is enabled
1 = transmitter is disabled,Uart does not send serial data out on the TX output pin after current data
in the TSR is send.
1
RW
Receiver Disable
0 = Receiver is enabled
1 = Receiver is disabled
0
RW
9-bit or Multidrop Mode Enable
0 = Normal 8-bit mode
1 = Enable 9-bit mode (addition bit defines data or address byte)
Offset 0DH: Special Features Enable Control Register (SFREN). Accessable when LCR==8'hBF. Default=00
Bit
Type
Description
[7:0]
RW
Set 8'h5A to enable SFR register access
Offset 02H: Advance Status Register (ASR). Accessable when LCR=0xBF and SFR[2]=1. Default=00
Bit
Type
Description
[7:6]
RO
Reserved
[5:4]
RO
Xon/Xoff flow state
00 = idle state
01 = Xoff received
10 = TX off
11 = Xon received
[3:2]
RO
Reserved
1
RO
Remote TX disabled
1 = TX has sent XOFF message or RTS message
0
RO
Transmitter terminate condition
1 = This TX has disabled by remote termiate.
Offset 04H: Clock Prescale Register (CPR). Accessable when LCR=0xBF and SFR[2]=1. Default=10
Bit
Type
Description
[7:4]
RW
CPRM - M number in calculating the prescaler,which is used to generate Baud Rate,it is recommended to be set to "01h" or "02h"
[3:0]
RW
CPRN - N number in calculating the prescaler,which is used to generate Baud Rate.
Offset 05H: Received FIFO Data counter Register (RFD). Accessable when LCR=0xBF and SFR[2]=1, SFR[6]=0.
Default=00
Bit
Type
Description
[7:0]
RO
Indicated the amount of data in RX FIFO
Offset 05H: Received Line Error Status counter Register (RLS). Accessable when LCR=0xBF and SFR[2]=1,
SFR[6]=1. Default=00
Bit
Type
Description
[7:0]
RO
Indicated the amount of data byte with error in RX FIFO
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Configuration Registers cont.
Offset 06H: Transmitter FIFO Data counter Register (TFD). Accessable when LCR=0xBF and SFR[2]=1. Default=00
Bit
Type
Description
[7:0]
RO
Indicated the amount of data in TX FIFO
Offset 07H: Special Function Register(SFR). Accessable when LCR=0xBF and SFREN==0x5A. Default=00
Bit
Type
Description
7
RW
If set, Crystal feedback resistor disable
6
RW
RFD/LSR counter select
0 = Receive FIFO Data Counter is selected
1 = Line Status Error Counter is selected
5
RW
Reserved
4
RW
Registers burst R/W enable if set
3
RW
enable the loopback from RX to TX internally
2
RW
Special Register Access Enable when set, registers(CPR,ISCR,TIDLE,TRCTL) are accessable.
1
RW
Auto DSR and DTR Flow Control enable
0 = Auto DSR and DTR Flow Control is disabled
1 = Auto DSR and DTR Flow Control is enabled
0
RW
If set, forces transmitter to always to transmit data
Offset 08H: Transmit Idle Time Count Register (TIDLE). Accessable when LCR=0xBF and SFR[2]=1. Default=00
Bit
Type
Description
[7:0]
RW
Transmit Idle Time control.
Offset 09H: TX/RX Control Register (SCR/TRCTL). Accessable when LCR=0xBF and SFR[2]=1. Default=06
Bit
Type
Description
[7:4]
RW
SCR - Sample Clock value used in the Baud Rate Generator.
Baud Rate = XIN / (DL * 2 ** (M+2*MCR[7]-1) * (16-SCR+N))
3
RW
Transmit In-band Xon enable
2
RW
TX Empty Interrupt enable
1
RW
RX Timeout enable
0
RW
TX Idle insertion enable
Note: When IrDA mode is enabled, the setting in register SCR(bit 7-3 of 09H) and N(bit 3-0 of CPR should meet: SCR=N or (16-SCR+N) > 1.
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Configuration Registers cont.
Offset 0FH: Interrupt Status and Clear Register (ISCR). Accessable when LCR=0xBF and SFR[2]=1. Default=00
Bit
Type
Description
7
RW
1 = CTS/RTS change Interrupt is active
6
RW
1 = Rx Xoff signal/special character Interrupt is active
5
RW
1 = Modem Interrupt is active
4
RW
1 = THR Interrupt is active
3
RW
1 = Receiver Timeout Interrupt is active
2
RW
1 = RHR Interrupt is active
1
RW
1 = Receive Line Error Interrupt is active
0
RW
CLSTATUS, when set, the Interrupt Status registers are cleared. This bit returns to zero after write.
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Maximum Ratings
(Above which useful life may be impaired. For user guidelines, not tested.)
Power Supply Range..........................................................................3.8V
Voltage at IO Pins....................................................... GND-0.3V to 5.5V
Storage Temperature .....................................................–65°C to +150°C
Package Dissipation.....................................................................500 mW
Junction Temperature (Tj)............................................................... 125oC
Note: Stresses greater than those listed under MAXIMUM
RATINGS may cause permanent damage to the device. This
is a stress rating only and functional operation of the device at
these or any other conditions above those indicated in the operational sections of this specification is not implied. Exposure
to absolute maximum rating conditions for extended periods
may affect reliability.
DC Electrical Characteristics
(TA = -40o to + 85oC, VDD = 1.62V - 3.63V)
VDD = 1.8V
± 10%
Symbol
Parameter
VDD = 2.5V
± 10%
VDD = 3.3V
± 10%
Min.
Max.
Min.
Max.
Min.
Max.
Unit
VILCK
Clock input low level
-0.3
0.3
-0.3
0.6
-0.3
0.6
V
VIHCK
Clock input high level
1.4
VDD
1.8
VDD
2.4
VDD
V
VIL
Input low voltage
-0.3
0.2
-0.3
0.5
-0.3
0.8
V
VIH
Input high voltage
1.4
5.5
1.8
5.5
2.0
5.5
V
VOL
VOH
Output low voltage
Output high voltage
0.4
0.4
1.4
1.8
0.4
2.0
Conditions
V
IOL = 4 mA
V
IOL = 2 mA
V
IOL = 1.5 mA
V
IOH = -1 mA
V
IOH = -400 uA
V
IOH = -200 uA
IIL
Input low leakage current
10
10
10
uA
IIH
Input high leakage current
10
10
10
uA
CIN
Input pin capacitance
5
5
5
pF
ICC
Power supply current
3
3
6
mA
ISLEEP
Sleep current
15
20
30
uA
XTAL1 = 14.75
MHz
Note: 5.5V steady voltage tolerance on inputs and outputs is valid only when the supply voltage is present.
AC Electrical Characteristics - UART Clock
(TA = -40o to + 85oC, VDD = 1.62V - 3.63V)
Symbol
Parameter
VDD = 1.8V
± 5%
VDD = 1.8V ±
10%
VDD = 2.5V ±
10%
VDD = 3.3V ±
10%
Min.
Min.
Min.
Min.
Max.
Max.
Max.
Max.
Unit
XTAL1
UART Crystal Oscillator
24
24
24
24
MHz
ECLK
UART External Clock
32
24
250
64
MHz
TECLK
External Clock Time Period
PI7C9X762
Document Number DS40306 Rev 4-2
1/ECLK
1/ECLK
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AC Electrical Characteristic - I2C-Bus Timing Specifications
(Unless otherwise noted: TA = -40o to +85oC, VDD = 1.62 - 3.63V)
Standard Mode
Symbol
Parameter
Fast Mode
Min.
Max.
Min.
Max.
Unit
0
100
0
400
kHz
f SCL
Operating frequency
TBUF
Bus free time between STOP and START
4.7
1.3
μs
THD;STA
START condition hold time
4.0
0.6
μs
TSU;STA
START condition setup time
4.7
0.6
μs
THD;DAT
Data hold time
0
0
ns
TVD;ACK
Data valid acknowledge
0.6
0.6
μs
TVD;DAT
SCL LOW to data out valid
0.6
0.6
μs
TSU;DAT
Data setup time
250
150
ns
TLOW
Clock LOW period
4.7
1.3
μs
THIGH
Clock HIGH period
4.0
0.6
μs
TF
Clock/data fall time
300
300
ns
TR
Clock/data rise time
1000
300
ns
TSP
Pulse width of spikes tolerance
100
100
ns
TD1
I2C-bus GPIO output valid
0.2
0.2
μs
TD2
I2C-bus modem input interrupt valid
0.2
0.2
μs
TD3
I2C-bus modem input interrupt clear
0.2
0.2
μs
TD4
I2C input pin interrupt valid
0.2
0.2
μs
TD5
I2C input pin interrupt clear
0.2
0.2
μs
TD6
I2C-bus receive interrupt valid
0.2
0.2
μs
TD7
I2C-bus receive interrupt clear
0.2
0.2
μs
TD8
I2C-bus transmit interrupt clear
1.0
0.5
μs
TD15
SCL delay after reset
3
3
μs
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RESET#
TD15
SCL
Figure 1. SCL Delay After Reset
START
condition
(S)
Protocol
Bit 7
MSB
(A7)
TLOW
TSU;STA
Bit 0
LSB
(R/W)
Bit 6
(A6)
Acknowledge
(A)
STOP
condition
(P)
TD15
THIGH
1/FSCL
SCL
TF
TBUF
TSP
TR
SDA
THD;STA
TSU;DAT
THD;DAT
TVD;DAT
TVD;ACK
TSU;STO
Figure 2. I2C-Bus Timing Diagram
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SDA
SLAVE
ADDRESS
W
A
IOSTATE REG.
A
DATA
A
TD1
GPIOn
Figure 3. Write To Output
SDA
SLAVE
ADDRESS
W
A
MSR REGISTER
A S
SLAVE
ADDRESS
R A
DATA
A
IRQ#
TD2
TD3
MODEM pin
Figure 4. Modem Input Pin Interrupt
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ACK from slave
SDA
SLAVE
ADDRESS
W
A
MSR REGISTER
A S
ACK from slave
SLAVE
ADDRESS
R A
ACK from master
DATA
A P
IRQ#
TD4
TD5
GPIOn
Figure 5. GPIO Pin Interrupt
Stop bit
Start bit
Next start bit
RX
TD6
IRQ#
Figure 6. Receive Interrupt
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SDA
SLAVE
ADDRESS
W
A
A S
RHR
SLAVE
ADDRESS
R A
DATA
A P
IRQ#
TD7
Figure 7. Receive Interrupt Clear
SDA
SLAVE
ADDRESS
W
A
THR REGISTER
A
DATA
A
DATA
A
IRQ#
TD8
Figure 8. Transmit Interrupt Clear
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AC Electrical Characteristic - SPI-Bus Timing Specifications
(Unless otherwise noted: TA = -40o to +85oC, VDD = 1.62 - 3.63V)
VDD =
1.8V±10%
Symbol
Parameter
Min. Max.
VDD =
2.5V±10%
Min.
Max.
VDD =
3.3V±10%
Min.
Max.
Unit
f SCL
SPI clock frequency
18
27
33
MHz
TTR
CS# HIGH to SO three-state time
100
100
100
ns
TCSS
CS# to SCL setup time
100
100
100
ns
TCSH
CS# to SCL hold time
20
20
20
ns
TDO
SCL fall to SO valid time
TDS
SI to SCL setup time
6.0
5.0
4.0
ns
TDH
SI to SCL hold time
0
0
0
ns
TCP
SCL period time
56
36
30
ns
TCH
SCL HIGH time
28
18
15
ns
TCL
SCL LOW time
28
18
15
ns
TCSW
CS# HIGH pulse width
200
200
200
ns
TD9
SPI output data valid
200
200
200
ns
TD10
SPI modem output data valid
200
200
200
ns
TD11
SPI transmit interrupt clear
200
200
200
ns
TD12
SPI modem input interrupt clear
200
200
200
ns
TD13
SPI input pin interrupt clear
200
200
200
ns
TD14
SPI receive interrupt clear
200
200
200
ns
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Document Number DS40306 Rev 4-2
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42
13
11
ns
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Condition
CL = 70 pF
CL = 70 pF
TCH + TCL
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CS#
TCSH
TCSS
TCL
TCH
TCSH
TCSW
SCLK
TDS
TDH
SI
TTR
TDO
SO
Figure 9. SPI-bus Timing
CS#
SCLK
SI
R/W
A3
A2
A1
A0
0
CH
X
D7
D6
D5
D4
D3
D2
D1
D0
TD9
GPIOx
Figure 10. SPI Write MCR To DTR Output Switch
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CS#
SCLK
SI
R/W
A3
A2
A1
A0
0
CH
X
D7
D6
D5
D4
D3
D2
D1
D0
TD10
DTR#
(GPIO5)
Figure 11. SPI Write MCR To DTR Output Switch
CS#
SCLK
SI
R/W
A3
A2
A1
A0
0
CH
X
D7
D6
D5
D4
D3
D2
D1
D0
GPIOx
td11
IRQ#
Figure 12. SPI Write THR To Clear TX INT
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CS#
SCLK
SI
R/W
A3
A2
A1
A0
0
CH
X
SO
D7
D6
D5
D4
D3
D2
D1
D0
TD12
IRQ#
Figure 13. Read MSR To Clear Modem INT
CS#
SCLK
SI
R/W
A3
A2
A1
A0
0
CH
X
SO
D7
D6
D5
D4
D3
D2
D1
D0
TD13
IRQ#
Figure 14. Read IOState To Clear GPIO INT
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CS#
SCLK
SI
R/W
A3
A2
A1
A0
0
CH
X
SO
D7
D6
D5
D4
D3
D2
D1
D0
TD14
IRQ#
Figure 15. Read RHR To Clear RX INT
Part Marking
L Package ZH Package
PI7C9X762CLE PI7C9X762CZHE
PI7C9X
762CLE
YYWWXX
YYWW: Year & Workweek
1st X: Assembly Site Code
2nd X: Fab Site Code
PI7C9X762
Document Number DS40306 Rev 4-2
PI7C9X
762CZHE
YYWWXX
YYWW: Year & Workweek
1st X: Assembly Site Code
2nd X: Fab Site Code
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Packaging Mechanical: 28-TSSOP (L)
16-0076
PI7C9X762
Document Number DS40306 Rev 4-2
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Packaging Mechanical: 32-TQFN (ZH)
17-0570
For latest package info.
please check: http://www.diodes.com/design/support/packaging/pericom-packaging/packaging-mechanicals-and-thermal-characteristics/
Ordering Information
Ordering Number
PI7C9X762CLEX
PI7C9X762CZHEX
Package Code
L
ZH
Package Description
28-Contact, 173mil wide (TSSOP)
32-Contact, Thin Quad Flat No-Lead (TQFN)
Notes:
1. EU Directive 2002/95/EC (RoHS), 2011/65/EU (RoHS 2) & 2015/863/EU (RoHS 3) compliant. All applicable RoHS exemptions applied.
2. See http://www.diodes.com/quality/lead-free/ for more information about Diodes Incorporated’s definitions of Halogen- and Antimony-free, “Green” and Lead-free.
Thermal characteristics can be found on the company web site at www.diodes.com/design/support/packaging/
3. E = Pb-free and Green
4. X suffix = Tape/Reel
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IMPORTANT NOTICE
DIODES INCORPORATED MAKES NO WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, WITH REGARDS TO THIS DOCUMENT, INCLUDING, BUT NOT
LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE (AND THEIR EQUIVALENTS UNDER
THE LAWS OF ANY JURISDICTION).
Diodes Incorporated and its subsidiaries reserve the right to make modifications, enhancements, improvements, corrections or other changes without further notice to this document and any product described herein. Diodes Incorporated does not assume any liability arising out of the application or use of this document or
any product described herein; neither does Diodes Incorporated convey any license under its patent or trademark rights, nor the rights of others. Any Customer
or user of this document or products described herein in such applications shall assume all risks of such use and will agree to hold Diodes Incorporated and all
the companies whose products are represented on Diodes Incorporated website, harmless against all damages.
Diodes Incorporated does not warrant or accept any liability whatsoever in respect of any products purchased through unauthorized sales channel.
Should Customers purchase or use Diodes Incorporated products for any unintended or unauthorized application, Customers shall indemnify and hold Diodes
Incorporated and its representatives harmless against all claims, damages, expenses, and attorney fees arising out of, directly or indirectly, any claim of personal
injury or death associated with such unintended or unauthorized application.
Products described herein may be covered by one or more United States, international or foreign patents pending. Product names and markings noted herein
may also be covered by one or more United States, international or foreign trademarks.
This document is written in English but may be translated into multiple languages for reference. Only the English version of this document is the final and determinative format released by Diodes Incorporated.
LIFE SUPPORT
Diodes Incorporated products are specifically not authorized for use as critical components in life support devices or systems without the express written approval
of the Chief Executive Officer of Diodes Incorporated. As used herein:
A. Life support devices or systems are devices or systems which:
1. are intended to implant into the body, or
2. support or sustain life and whose failure to perform when properly used in accordance with instructions for use provided in the labeling can be reasonably
expected to result in significant injury to the user.
B. A critical component is any component in a life support device or system whose failure to perform can be reasonably expected to cause the
failure of the life support device or to affect its safety or effectiveness.
Customers represent that they have all necessary expertise in the safety and regulatory ramifications of their life support devices or systems, and acknowledge
and agree that they are solely responsible for all legal, regulatory and safety-related requirements concerning their products and any use of Diodes Incorporated
products in such safety-critical, life support devices or systems, notwithstanding any devices- or systems-related information or support that may be provided by
Diodes Incorporated. Further, Customers must fully indemnify Diodes Incorporated and its representatives against any damages arising out of the use of Diodes
Incorporated products in such safety-critical, life support devices or systems.
Copyright © 2016, Diodes Incorporated
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Revision History
Date
8/14/2014
Revision
0.1
Description
First Release
Updated the AC Electrical Characteristic - I2C-Bus Timing Specifications
Updated the SPI Bus Interface
10/21/2014
0.1
Updated the Feature
Updated the Description
Updated Configuration Register
Updated the Maximum Rating
05/13/2015
1.0
05/25/2016
1.1
12/14/2016
1.2
06/05/2017
1.3
Remove C from part numbers except ordering information
10/20/2017
2
Revision numbering system changed to whole number
Updated the Ordering Information
Updated the Packaging Mechanical
Chnage the revision to C
Updated the Maximum Ratings
Updated the Pin Configuration 32-Pin TQFN (I2C-Bus Interface) Diagram
04/27/2018
3
Updated the Ordering Information
Added Part Marking
05/09/2018
PI7C9X762
Document Number DS40306 Rev 4-2
4
Updated Configuration Registers
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