Thytronic SIF5600 - 3.10 Function 08: Loopback Diagnostic Test

75
75
SIF5600 - Manual - 03 - 2008
Response: the confirmation response is identical to the request message.
where:
ADR reference to the data structure of WREG:
ADR=0 if NUM=1, ADR=1 if NUM=2, ... etc.
VALUE writing value (only one register)
3.9 Function 16: Preset multiple register WREG
Body field framing:
Request:
| ADR | DIM |NBYTES| WREG1 | ... | WREG(DIM) |
| H | L | H | L | | H | L | ... | H | L |
|------|------|------|------|------|------|------| |--------|------|
byte 1 byte 2 byte 3 byte 4 byte 5 byte 6 byte 7 ... byte n-1 byte n
Response:
| ADR | DIM |
| H | L | H | L |
|------|------|------|------|
byte 1 byte 2 byte 3 byte 4
where:
ADR reference to the data structure of WREG class:
ADR=0 if NUM=1, ADR=1 if NUM=2, ... etc.
DIM size of the WREG data structure(number of registers)
NBYTES number of bytes from WREG1 to WREG(DIM): double of DIM
WREG1.. writing registers
3.10 Function 08: loopback diagnostic test
MODBUS function code 08 provides a test for checking the communication system between a Master and a Slave.
The response message is identical to the request.
The contents of some remote device’s diagnostic register are returned in the response; the diagnostic
register are cleared.
Message framing:
Request:
| CODE | DATA |
| H | L | H | L |
|------|------|------|------|
byte 1 byte 2 byte 3 byte 4
Response:
| CODE | INFO |
| H | L | H | L |
|------|------|------|------|
byte 1 byte 2 byte 3 byte 4
where:
CODE diagnostic test code
DATA accessory data for diagnostic function
INFO data returned from diagnostic test
Here the list of diagnostic codes supported by the serial line devices:
- return query data (loopback) Request: CODE = 0, DATA = 12345
Response: INFO = DATA
- return Diagnostic Register Request: CODE = 2, DATA = 0
Response: INFO = diagnostic register
- clear Diagnostic Register Request: CODE = 10, DATA = 0
Response: INFO = 0
- return Bus Message Count Request: CODE = 11, DATA = 0
Response: INFO = counter
- return Bus Communication Error Count Request: CODE = 12, DATA = 0
Response: INFO = counter
- return Bus Exception Error Count Request: CODE = 13, DATA = 0
Response: INFO = counter