Trycom Technology TRP-C28 User Manual page 22

Start bit: 1
Data bit: 8
Parity check: None
Stop bit: 1
Baud-rate: 1200bps~115200bps.
9-1. Modbus Syntax:
Command Format :ID(HEX)+FC(HEX)+SU(HEX)+DA(HEX) or RC(HEX)+CRC16(HEX).
Response Format : ID(HEX)+FC(HEX)+SU(HEX)+DA(HEX) or RC(HEX)+CRC16(HEX).
Error Format: ID(HEX)+ FC(HEX)+ CRC16(HEX).
ID: RS485 Device Address (HEX).....1~247 1Byte.
FC: Function Code (HEX)...1 Byte.
SU: Sub Function (HEX).....1 Byte
DA: Data Format....No Limit
RC: Reserved code...No Limit
CRC: Cyclic Redundancy Check...2 Byte
*Error Response: If CRC IS mismatches error the response is empty!
10. Modbus RTU Command List
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