ST75MM

UM2241 User manual METERS AND MORE® compliant power line communication system-on-chip Introduction This user manual, which targets application developers, provides complete information on how to use the ST75MM in applications by describing the host interface, the available protocol services and the MIB accessible through the host interface. For ordering information, mechanical and electrical device characteristics, please refer to the ST75MM datasheet available at www.st.com. August 2017 DocID030767 Rev 1 1/26 www.st.com Contents UM2241 Contents 1 2 Host interface .................................................................................. 6 1.1 Settings ............................................................................................. 6 1.2 Operations......................................................................................... 6 1.3 Acknowledge ..................................................................................... 7 1.4 Command frame format .................................................................... 7 1.5 Status message frame format (SM) .................................................. 7 1.6 TREQ management .......................................................................... 9 1.7 Examples .......................................................................................... 9 Host interface commands ............................................................. 14 2.1 Commands ...................................................................................... 14 2.2 Error codes...................................................................................... 14 2.3 MIB_Write ....................................................................................... 15 2.4 2.5 2.6 2.3.1 MIB_Write request ............................................................................ 15 2.3.2 MIB_Write positive confirm ............................................................... 15 2.3.3 MIB_Write negative confirm ............................................................. 15 2.3.4 MIB_Write indication......................................................................... 15 MIB_Read ....................................................................................... 15 2.4.1 MIB_Read request............................................................................ 16 2.4.2 MIB_Read positive confirm .............................................................. 16 2.4.3 MIB_Read negative confirm ............................................................. 16 BIO_Reset....................................................................................... 16 2.5.1 BIO_Reset request ........................................................................... 16 2.5.2 BIO_Reset positive confirm .............................................................. 16 2.5.3 BIO_Reset negative confirm ............................................................ 17 2.5.4 BIO_Reset indication ........................................................................ 17 DL_DATA_SLAVE .......................................................................... 17 2.6.1 2.7 2.8 HI_Ping ........................................................................................... 18 2.7.1 HI_PING request .............................................................................. 18 2.7.2 HI_PING positive confirm ................................................................. 18 HI_Error .......................................................................................... 18 2.8.1 3 HI_ERROR indication ....................................................................... 18 Management information base (MIB) ........................................... 19 3.1 2/26 DL_DATA_SLAVE indication ........................................................... 17 MIB objects ..................................................................................... 19 DocID030767 Rev 1 UM2241 4 5 Contents Configuring the ST75MM .............................................................. 23 4.1 PHY configuration (MIB index 2) ..................................................... 23 4.2 MAC configuration (MIB index 3) .................................................... 24 4.3 Manufacturer data (MIB index 6) ..................................................... 24 4.4 Custom frequencies (MIB index 23) ................................................ 24 Revision history ............................................................................ 25 DocID030767 Rev 1 3/26 List of tables UM2241 List of tables Table 1: Command frame format ................................................................................................................ 7 Table 2: Status message format ................................................................................................................. 7 Table 3: Modem status format .................................................................................................................... 8 Table 4: MIB status format .......................................................................................................................... 8 Table 5: Available commands ................................................................................................................... 14 Table 6: List of error codes ....................................................................................................................... 14 Table 7: Reset cause byte format ............................................................................................................. 17 Table 8: MIB objects list ............................................................................................................................ 19 Table 9: MAC data MIB object (1) ............................................................................................................ 19 Table 10: PHY configuration MIB object (2) ............................................................................................. 19 Table 11: MAC configuration MIB object (3) ............................................................................................. 20 Table 12: Manufacturer data MIB object (6) ............................................................................................. 21 Table 13: Host interface timings MIB object (14) ...................................................................................... 21 Table 14: ZC alarm MIB object (18) .......................................................................................................... 21 Table 15: PHY custom frequencies MIB object (23) ................................................................................. 21 Table 16: PHY statistics MIB object (24) .................................................................................................. 21 Table 17: PHY configuration values for CENELEC 132.5 kHz operations ............................................... 23 Table 18: MAC configuration values for CENELEC 132.5 kHz operations .............................................. 24 Table 19: Document revision history ........................................................................................................ 25 4/26 DocID030767 Rev 1 UM2241 List of figures List of figures Figure 1: Host controller to ST75MM connection scheme.......................................................................... 6 Figure 2: TREQ negotiation timing diagram ............................................................................................... 9 Figure 3: DL_DATA_SLAVE.indication transaction .................................................................................. 10 Figure 4: DL_DATA_SLAVE.indication transaction in case of no ack ...................................................... 11 Figure 5: MIB_Write.request transaction .................................................................................................. 12 Figure 6: MIB_Read.request transaction .................................................................................................. 13 DocID030767 Rev 1 5/26 Host interface UM2241 1 Host interface 1.1 Settings The host interface is used to interface the ST75MM to the host controller, it allows exchanging data, configuration and control messages. The host interface can be managed by the host controller with a half-duplex asynchronous serial port (UART) plus an additional synchronization signal which will be referenced, in this document as TREQ. The configuration at the host controller shall be the following one:   2-wire UART port set to (57600, 1, N, 1) no flow control Single wire push-pull output (TREQ line) Figure 1: Host controller to ST75MM connection scheme 1.2 Operations Being the communication link between the host controller and the ST75MM a half-duplex serial link, the communication paradigm is master/slave, where the ST75MM acts as the master of the communication. When an event is triggered inside the ST75MM (incoming PLC frame, completion of requested activities or error/warning events), this is automatically and immediately sent to the host controller through the serial link. This means that the host controller should continuously monitor the UART port, decode the frames as they are detected and send an acknowledge message to the ST75MM. When the host controller needs to send a command to the ST75MM (data request or MIB programming/reading) it shall drive low the TREQ signal (which indeed needs to remain high when idle) and wait for the ST75MM to send a special message, the so called "Status Message" (SM). As the SM holds information about the availability of the ST75MM to receive commands, it shall be detected by the host controller before sending the message request to the ST75MM. The ST75MM will respond immediately to the host controller with an acknowledge byte and, if the command requires a further communication (e.g., the result of the command) will be sent as an internally triggered event (see previous paragraph) once the operations inside the ST75MM are concluded. 6/26 DocID030767 Rev 1 UM2241 Host interface Section 1.7: "Examples" contains some examples on how complex operations shall be managed between the host controller and the ST75MM. 1.3 Acknowledge In order to improve the serial link robustness, every frame except the SM must be acknowledged by the receiver within a given period T ACK (host interface timings are managed through a dedicated MIB object, see Section 3.1: "MIB objects" for reference), otherwise the sender will repeat once the same message waiting for a new acknowledge. If no acknowledge arrives after the second message is sent, the message is discarded by the sender and no further repetitions are sent. If the sender is the ST75MM, no further action is taken. The acknowledge byte is only linked to the format of the frame, and shall never give feedback on the validity or execution of the command; it can have two values:   1.4 0x06 (ACK) which means that the received command is well formed 0x15 (NAK) which means that the received command has errors (length or CRC). Command frame format Commands are formatted as follows: Table 1: Command frame format Starting Byte Field Size Value Description Used to mark the start of a command. In order for the host controller to distinguish between a message and its repetition(1). The frame start has always the value 0x02, except for repeated messages, where a value of 0x03 is used. When the host controller receives a message starting with 0x03 it should verify if the same message has already been received, and, in this case, discards the latter one. 0 Frame start 1 0x02 / 0x03 1 Length 1 Any Number of payload bytes after the first one (always sent). 2 Command code 1 Any Identifies the command to be executed. 3 Payload 1...256 Any Contains the parameters associated with the command. Length + 4 Checksum 2 Any Sum of the Length, Command code and Payload fields. The sum is performed byte-wise, represented as 16-bit value and sent to the host controller MSB first. Notes: (1)This condition is generated when the modem doesn’t receive the ACK message from the host controller within the proper TACK time. 1.5 Status message frame format (SM) The SM is formatted as follows: Table 2: Status message format Starting Byte Field Size Value DocID030767 Rev 1 Description 7/26 Host interface UM2241 Starting Byte Field Size Value 0 SM start 1 0x3F Used to mark the start of the SM 1 Modem status 1 Any Bit mask showing the status of the ST75MM modem 2 MIB status 2 Any Bit mask showing which MIB objects have been reconfigured by the host controller Description The following table shows the modem status field possible values. Table 3: Modem status format Bit Sub-field Values 0 SET 0 1 The ST75MM modem has an internal configuration error. The ST75MM modem is configured and running properly. 1 TX 0 1 The ST75MM is not transmitting. The ST75MM is transmitting. 2 RX 0 1 The ST75MM is not in active reception state. The ST75MM is receiving a PLC frame. 3 PLC busy(1) 0 1 PHY layer is in idle state. PHY layer is busy or not yet configured. 4 OVC 0 1 No overcurrent events registered during the last transmission. At least one overcurrent event registered during the last transmission. 5 Reserved - - 00(2) 6-7 Temperature 01 10 11 Description ST75MM temperature is lower than 70 °C. ST75MM temperature is between 70 °C and 100 °C. ST75MM temperature is between 101 °C and 125 °C. ST75MM temperature is higher than 125 °C. Notes: (1)Before sending any command to the ST75MM the host controller should monitor this flag, proceeding only if the value is 0. (2)Values are always given as [msb]...[lsb], so a value of “01” means bit_7 = 0 and bit_6 = 1. The following table shows the correspondence between the MIB status field and the MIB configuration, if the MIB has been configured (or correctly reconfigured after a reset event) the corresponding bit is raised, otherwise is set to 0. Table 4: MIB status format 8/26 Bit Name MIB index Description 0 Reserved - - 1 Reserved - - 2 PHY configuration 2 Current PHY layer configuration 3 MAC configuration 3 Current MAC layer configuration 4 Reserved - - 5 Reserved - - DocID030767 Rev 1 UM2241 1.6 Host interface Bit Name MIB index Description 6 Manufacturer data 6 Physical address (ACA) of the modem and serial number 7 Reserved - - 8 Reserved - - 9 Reserved - - 10 Reserved - - 11 Reserved - - 12 Reserved - - 13 Reserved - - 14 Reserved - - 15 Reserved - - TREQ management Here below a timing diagram of the priority negotiation of the serial link is depicted, first of all the host controller wanting to send a command to the ST75MM drives low the TREQ line, waiting for the SM frame before sending the message. As soon as the SM frame starts, the host controller drives high the TREQ line and, when the SM is completely received, it verifies that PLC Busy flag is disabled. If the PLC Busy flag of the SM is disabled the host controller sends the command to the ST75MM within TSR time, and waits for a maximum of T ACK time the acknowledge byte from the ST75MM. If the acknowledge byte is not received within T ACK time, the host controller can initiate a new transaction, sending the same command with 0x03 as start of the frame byte, this way, if the acknowledge byte has been lost in the serial link the ST75MM receives the command twice and can disregard the repetition. Figure 2: TREQ negotiation timing diagram 1.7 Examples Here below an example of DL_DATA_SLAVE.indication coming from the ST75MM, in this case, as in MIB_Write.indication, being the message triggered by the ST75MM there is no negotiation with the host controller in the serial link. DocID030767 Rev 1 9/26 Host interface UM2241 Figure 3: DL_DATA_SLAVE.indication transaction The same transaction, in case the acknowledge (the same applies in case the –indication is lost) is lost, is the one depicted in the next figure, where the second DL_DATA_SLAVE.indication message frame uses 0x03 as start of the frame byte instead 0x02 as the first one, to let the host controller check if the message has already been received or not. . 10/26 DocID030767 Rev 1 UM2241 Host interface Figure 4: DL_DATA_SLAVE.indication transaction in case of no ack This is an example of the MIB_Write request coming from the host controller, as the initiator is the host controller, the session is started with the negotiation with the ST75MM to gain priority on the serial link DocID030767 Rev 1 11/26 Host interface UM2241 Figure 5: MIB_Write.request transaction The MIB_Read request coming from the host controller follows the same mechanism as the MIB_Write. 12/26 DocID030767 Rev 1 UM2241 Host interface Figure 6: MIB_Read.request transaction DocID030767 Rev 1 13/26 Host interface commands UM2241 2 Host interface commands 2.1 Commands The following table is a summary of the available commands, each command will be better specified later on. Table 5: Available commands Command .indication .confirm (negative) Description MIB_Write 0x08 0x09 0x0A 0x0B Modifies the value of a specific MIB object (.request) or notifies about an internally triggered modification (.indication). MIB_Read 0x0C 0x0D - 0x0F Reads the current value of a specific MIB object. DL_DATA_SLAVE - - 0x26 - Notifies about data packet received over the power line. HI_Ping 0x2C 0x2D - - Host interface loop, used to monitor the healthy state of the serial link and modem. HI_Error - - - 0x36 Notifies about the reception of an unknown command. 0x3F Triggers a SW reset (.request) or notifies about an internally triggered reset event (.indication). BIO_Reset 2.2 .request .confirm (positive) 0x3C 0x3D 0x3E Error codes Table 6: List of error codes 14/26 Value Error Description 0x02 WPL Wrong argument or parameter length 0x03 WPV Wrong argument or parameter value 0x04 BUSY Subsystem which is supposed to perform the operation is busy 0x06 NOT_PRESENT Subsystem which is supposed to perform the operation is either not present or not connected 0x07 DISABLED Subsystem which is supposed to perform the operation is disabled 0x08 TIMEOUT The operation has not been performed in the proper time 0xFF ERROR Generic error DocID030767 Rev 1 UM2241 2.3 Host interface commands MIB_Write This command is initiated by the host controller to request a modification on a specific MIB object, the MIB object index and the expected new value are embedded in the payload of the .request message, while the .confirm messages carry the information about the success of the operation. The indication message is issued by the ST75MM modem when some specific MIB objects change their values due to the internal state and events or following a request coming from the PLC. 2.3.1 MIB_Write request Issued by: host controller Command code: 0x08 Payload size: variable Payload content:   2.3.2 MIB object index (1 byte) MIB content (variable) MIB_Write positive confirm Issued by: ST75MM Command code: 0x09 Payload size: 1 byte Payload content:  2.3.3 MIB object index (1 byte) MIB_Write negative confirm Issued by: ST75MM Command code: 0x0B Payload size: 1 byte Payload content:  2.3.4 Error code (1 byte) MIB_Write indication Issued by: ST75MM Command code: 0x0A Payload size: variable Payload content:   2.4 MIB object index (1 byte) MIB value (variable) MIB_Read This command is initiated by the host controller to request the current value of a specific MIB object, the MIB object index is specified in the payload of the .request message, while the .confirm messages hold the MIB object index and its current value. DocID030767 Rev 1 15/26 Host interface commands 2.4.1 UM2241 MIB_Read request Issued by: host controller Command code: 0x0C Payload size: 1 byte Payload content:  2.4.2 MIB object index (1 byte) MIB_Read positive confirm Issued by: ST75MM Command code: 0x0D Payload size: variable Payload content:  2.4.3 MIB current value (variable) MIB_Read negative confirm Issued by: ST75MM Command code: 0x0F Payload size: 1 byte Payload content:  2.5 Error code (1 byte) BIO_Reset These commands are exchanged when the host controller needs to force a SW reset to the ST75MM modem (request), at the power-on, after a hardware reset or when the ST75MM modem reaches an instability state and internally triggers a SW reset (indication). 2.5.1 BIO_Reset request Issued by: host controller Command code: 0x3C Payload size: 1 byte Payload content:  2.5.2 Reserved (1 byte) – set to 0 BIO_Reset positive confirm Issued by: ST75MM Command code: 0x3D Payload size: 1 byte Payload content:  16/26 Reserved (1 byte) DocID030767 Rev 1 UM2241 2.5.3 Host interface commands BIO_Reset negative confirm Issued by: ST75MM Command code: 0x3F Payload size: 1 byte Payload content:  2.5.4 Error code (1 byte) BIO_Reset indication Issued by: ST75MM Command code: 0x3E Payload size: 1 byte Payload content:  Reset cause (1 byte) Table 7: Reset cause byte format Bit 2.6 Field Value 06 Reset cause 0 1 2 3 4 5 6 7 8127 7 Reconfiguration status 0 1 Description Power-on or HW reset Watchdog SW reset BIO_Reset request PHY error (diagnostic) Timer or zero crossing (diagnostic) Inconsistent state (diagnostic) PHY layer error (diagnostic) Reserved One or more reconfigurable MIB objects have not been properly reconfigured after reset. All the reconfigurable MIB objects have been correctly reconfigured after reset. DL_DATA_SLAVE The DL_DATA_SLAVE commands provide data communication as a slave node (e.g. the meter in meter to concentrator communication or the customer device in meter to home communication). 2.6.1 DL_DATA_SLAVE indication Issued by: ST75MM Command code: 0x26 Payload size: variable Payload content:   Protocol type (1 byte) Request ID (1 byte) DocID030767 Rev 1 17/26 Host interface commands  UM2241 Applicative payload (variable) Only commands having the protocol type equal to 0 shall be processed, if a command with a different protocol type is received it shall be discarded and no action performed. 2.7 HI_Ping HI_Ping commands can be used to periodically test the serial link between the host controller and the ST75MM modem, and the healthy state of the modem itself. If the HI_Ping fails (once or several times) a hardware reset shall be issued to restore the ST75MM functionalities. 2.7.1 HI_PING request Issued by: host controller Command code: 0x2C Payload size: variable Payload content:  Test sequence (variable) The test sequence can be any possible sequence and length (between 1 and 256). 2.7.2 HI_PING positive confirm Issued by: ST75MM Command code: 0x2D Payload size: variable Payload content:  Test sequence (variable) The test sequence is the same received within the request command. 2.8 HI_Error This command is issued by the ST75MM when a well formed command frame is received but the command code has not been recognized. 2.8.1 HI_ERROR indication Issued by: ST75MM Command code: 0x36 Payload size: 1 byte Payload content:  18/26 Command code received (1 byte) DocID030767 Rev 1 UM2241 Management information base (MIB) 3 Management information base (MIB) 3.1 MIB objects The following table shows the MIB objects present in the ST75MM modem, reserved MIB objects should not be modified and notifications involving those MIB objects can be ignored. Table 8: MIB objects list Index(1) Name Size Rights(2) 1 MAC data 12 RW 2 PHY configuration 6 RWCS PHY layer configuration 3 MAC configuration 2 RWCS MAC layer configuration 6 Manufacturer data 22 RWCS Node identification parameters 14 HI timings 3 RW Host interface (UART) timings 18 ZC alarm 1 RWI No zero crossing detected on mains alarm 23 PHY custom frequency 17 RWC Custom frequency setting 24 PHY statistics 9 RW Description Statistical information related to MAC layer PHY layer statistics Notes: (1)Objects not listed here with index in the range (0, 34) are reserved objects, the host controller should avoid to change their values and disregard any MIB_Write indication related to them. (2)R = read, W = write, C = self-reconfigured at startup, S = affect MIB state in SM, I = can generate spontaneous MIB_Write.indication Table 9: MAC data MIB object (1) Byte Field Bit Sub-field - Refused UW - Bad CRC Counter of incoming packets discarded for wrong CRC 4-5 - Rx packet Counter of packets received by MAC 6-7 - Refused packets Not relevant - Requested packets Not relevant - Timeouts Not relevant 0-1 2-3 8-9 RX stats TX stats 1011 Description and values Counter of incoming packets rejected as MAC was busy Table 10: PHY configuration MIB object (2) Byte Field Bit Sub-field 0 General settings 0 Current control Description and values 0: current control disabled 1: current control enabled DocID030767 Rev 1 19/26 Management information base (MIB) Byte Field UM2241 Bit Sub-field Description and values 1 Zero crossing 2 RX channel 0: single channel operations 1: dual channel operations 3 TX channel 0: transmit on high channel 1: transmit on low channel 45 Frequency pair 6 BU enable 7 CSMA enable 04 TX gain Reserved 0: CSMA not enabled 1: CSMA enabled Gain, in dB, applied in transmission TX modulation Modulation used in transmission: 0 to 3: reserved 4: BPSK coded 5: QPSK coded 6 to 7: reserved 01 PSK preamble 0:16 bits preamble 1: 24 bits preamble 2: 32 bits preamble 3: 40 bits preamble 2 RX low channel Receiving mode for lower channel 0: FSK modulation 1: any PSK modulation 3 RX high channel Receiving mode for higher channel 0: FSK modulation 1: any PSK modulation 47 Reserved - - Reserved - 57 3-5 0, 1, 2: reserved 3: custom frequency (see MIB 23 for channel frequencies) 0: band in use, detector not enabled 1: band in use, detector enabled 1 2 0: next transmitted frame will start immediately 1: next transmitted frame will start at the next zero crossing event Table 11: MAC configuration MIB object (3) Byte 0 1 20/26 Field RX mode TX mode Bit - - Sub-field Description and values - 0: RX disable 1: RX normal 2 to 255: reserved - 0: TX disable 1: TX normal 2 to 255: reserved DocID030767 Rev 1 UM2241 Management information base (MIB) Table 12: Manufacturer data MIB object (6) Byte Field Bit Sub-field Description and values 0-15 Device ID - - Device identification string 16-21 ACA - - Physical address of the node (ACA) Table 13: Host interface timings MIB object (14) Byte Field Bit Subfield 0 TSR - - Maximum time (ms) between the SM reception and the start of the request from the host controller 1 TACK - - Maximum time (ms) between the end of the command frame and the start of transmission of the acknowledge byte 2 TIC - - Maximum time (ms) between two characters before an end of the command frame is detected Description and values Table 14: ZC alarm MIB object (18) Byte Field Bit Subfield 0 ZC Alarm - - Description and values 0: ZC events on the mains are regular 1: ZC detection on mains failed at least once since the last reset of the attribute Table 15: PHY custom frequencies MIB object (23) Byte Field Bit Subfield Description and values 0-5 TX frequency - - Set to {0x08, 0x7A, 0xE1, 0x07, 0x0A, 0x3D} for 132.5 kHz / 110 kHz frequency pair 6-11 RX frequencies - - Set to { 0x07, 0xC2, 0x8F, 0x09, 0x5C, 0x29} for 132.5 kHz / 110 kHz frequency pair 1216 Reserved - - Always set to { 0x00, 0x00, 0x00, 0x00, 0x00 } Table 16: PHY statistics MIB object (24) Byte Field Bit Sub-field 1-2 - Received frames 3-4 - Transmitted frames 5-6 - Refused frames Counter of frames requested but not transmitted due to errors in the request or the overtemperature state of the modem 7 - Skipped frames Counter of frames requested but not transmitted due to busy channel conditions PHY statistics Description and values Counter of received frames Counter of transmitter frames DocID030767 Rev 1 21/26 Management information base (MIB) Byte 22/26 Field UM2241 Bit Sub-field 8 - Discarded frames 9 - Overcurrent events Description and values Counter of frames discarded from the MAC layer due to busy upper layers condition Number of overcurrent events in the last transmitted frame DocID030767 Rev 1 UM2241 4 Configuring the ST75MM Configuring the ST75MM Only the four MIB objects detailed below need to be programmed/monitored to ensure correct operation as receiver-only in the CENELEC 132.5 kHz band. 4.1 PHY configuration (MIB index 2) In order to configure the ST75MM modem to work as a single channel receiver in the CENELEC 132.5 kHz band the MIB object 2 shall be programmed with the following string: {0x31, 0x95, 0x0A, 0x3B, 0x58, 0x9B} Corresponding to the following configuration (selected values are in bold). Table 17: PHY configuration values for CENELEC 132.5 kHz operations Byte Field Bit Sub-field 0 Current control 1 Zero crossing 2 RX channel 3 TX channel 45 Frequency pair 6 BU enable 7 CSMA enable 04 TX gain Description and values 0: current control disabled 1: current control enabled 0: next transmitted frame will start immediately 0 General settings 1 57 01 TX modulation 1: next transmitted frame will start at the next zero crossing event 0: single channel operations (only high channel) 1: dual channel operations 0: transmit on high channel 1: transmit on low channel 0, 1, 2: reserved 3: custom frequency (see MIB 23 for channel frequencies) 0: band in use detector not enabled 1: band in use detector enabled 0: CSMA not enabled 1: CSMA enabled Gain, in dB, applied in transmission, default is 21 dB (TX gain = 21) Modulation used in transmission: 0 to 3: reserved 4: BPSK coded 5: QPSK coded 6 to 7: reserved PSK preamble 0:16 bits preamble 1: 24 bits preamble 2: 32 bits preamble 3: 40 bits preamble 2 2 RX low channel Receiving mode for lower channel 0: FSK modulation 1: any PSK modulation DocID030767 Rev 1 23/26 Configuring the ST75MM Byte 3-5 4.2 UM2241 Field Bit Sub-field 3 RX high channel 47 Reserved - - Reserved {0x3B, 0x58, 0x9B} Reserved Description and values Receiving mode for higher channel 0: FSK modulation 1: any PSK modulation MAC configuration (MIB index 3) In order to configure the ST75MM modem to work in the normal MAC mode the MIB object 3 shall be programmed with the following string: {0x01, 0x00} Corresponding to the following configuration (selected values are in bold). Table 18: MAC configuration values for CENELEC 132.5 kHz operations Byte 0 Field RX mode Bit - Sub-field - Description and values 0: RX disable 1: RX normal 2 to 255: reserved 0: TX disable 1 4.3 TX mode - - 1: TX normal 2 to 255: reserved Manufacturer data (MIB index 6) The modem identifier and the modem address selection are outside the scope of this document, anyhow, as soon as the manufacturer, or the network administrator, or any competent authority, have assigned those values, the host controller shall program it inside the modem by writing the MIB object 6. Until this operation the modem will be capable only of receiving broadcast frames, as no default valid address has been programmed into the ST75MM. In case no device ID is available, a dummy value could be used, as the only parameter which influences the communication is ACA. 4.4 Custom frequencies (MIB index 23) In order to configure the ST75MM modem to work as a single channel receiver in the CENELEC 132.5 kHz band the MIB object 2 shall be programmed with the following string: {0x08, 0x7A, 0xE1, 0x07, 0x0A, 0x3D, 0x07, 0xC2, 0x8F, 0x09, 0x5C, 0x29, 0x00, 0x00, 0x00, 0x00, 0x00} Which sets as a channel pair the couple (132.5 kHz, 110 kHz), as in single channel operations the ST75MM modem only operates in the high frequency channel. 24/26 DocID030767 Rev 1 UM2241 5 Revision history Revision history Table 19: Document revision history Date Revision Changes 09-Aug-2017 1 Initial release. DocID030767 Rev 1 25/26 UM2241 IMPORTANT NOTICE – PLEASE READ CAREFULLY STMicroelectronics NV and its subsidiaries (“ST”) reserve the right to make changes, corrections, enhancements, modifications, and improvements to ST products and/or to this document at any time without notice. Purchasers should obtain the latest relevant information on ST products before placing orders. ST products are sold pursuant to ST’s terms and conditions of sale in place at the time of order acknowledgement. Purchasers are solely responsible for the choice, selection, and use of ST products and ST assumes no liability for application assistance or the design of Purchasers’ products. No license, express or implied, to any intellectual property right is granted by ST herein. Resale of ST products with provisions different from the information set forth herein shall void any warranty granted by ST for such product. ST and the ST logo are trademarks of ST. All other product or service names are the property of their respective owners. Information in this document supersedes and replaces information previously supplied in any prior versions of this document. © 2017 STMicroelectronics – All rights reserved 26/26 DocID030767 Rev 1