ICP DAS USA M-7065 User Manual page 98

Response:
00 Address
01 Function code
02 Byte Count
03 Bit values
Error Response:
00 Address
01 Function code
02 Exception code
Examples:
Command:05 01 00 00 00 05 [ FD 8D ]
Response:05 01 01 1F 11 70
Reads digital output value
[Command]
Byte 2~3 : 00 00 (starting channel numbers)
Byte 4~5 : 00 05 (output channel number)
Byte 6~7 : FD 8D(CRC)
[Response]
Byte 1 : 01 (Function Code)
Byte 2 : 01 (Byte count of response)
Byte 3 : 1F (DO0~DO3 Value)
Byte 4~5 : 11 70 (CRC)
M-7065 User's Manual Ver2.0, Dec. /200 8 ---98
1 Byte
1 Byte
Byte count of response
1 Byte
(B=(bit count + 7)/8)
B Byte
1 Byte
1 Byte
Refer to Modbus standard
1 Byte
for more details
1-247
0x01
(Bit values)
1-247
0x81