42
03(0x03) Read Digital Input Count Value
Request
00 Address
1
Byte
1-247
01 Function
code 1
Byte
0x03
02~03 Starting channel
2 Bytes 0x0000~0x0003
04~05 Input channel
numbers
2 Bytes 0x0001~0x0004
Response
00 Address
1
Byte
1-247
01
Function code
1 Byte
0x03
02
Byte count
1 Byte
N*
x 2
03~ Input
channel
count value
N*
x 2
Byte
Each channel can record a maximum
count value up to 65535(0xFFFF).
N*=Number of input channels
Error Response
00 Address
1
Byte
1-247
01
Function code
1 Byte
0x83
02 Exception
code 1
Byte
Refer
to the Modbus standard for more
details.