5–69
Communication Protocol
ASCII Mode:
RTU Mode:
ADR (Communication Address)
Valid communication addresses are in the range of 0 to 254. A communication
address equal to 0 means broadcast to all AC drives, in which case the drives will
not reply any message to the master device.
For example, communication to AC drive with address 16 decimal:
ASCII mode: (ADR 1, ADR 0)='1','0' => '1'=31H, '0'=30H
RTU mode: (ADR)=10H
START A silent interval of more than 10 ms
ADR Communication Address: 8-bit address
CMD Command Code: 8-bit command
DATA (n-1)
Contents of data: n x 8-bit data, n ≤ 25.......
DATA 0
CRC CHK Low
CRC check sum: 16-bit check sum consists of 2 8-bit characters
CRC CHK High
END A silent interval of more than 10 ms
STX Start Character: (3AH)
ADR 1
Communication Address: 8-bit address consists of 2 ASCII codes
ADR 0
CMD 1
CMD 0
DATA (n-1)
Contents of data: n x 8-bit data consists of 2n ASCII codes. n ≤ 25
maximum of 50 ASCII codes
.......
DATA 0
LRC CHK 1
LRC check sum: 8-bit check sum consists of 2 ASCII codes
LRC CHK 0
END 1
END characters: END 1 = CR (0DH); END 0 = LF (0AH)
END 0
Chapter 5: DURAPULSE MODBUS Communications
DURAPULSE AC Drive User Manual
1st Ed. Rev. D 05/2013