Nortech EasyGrid V1, User Manual, Page: 85 / 114

EasyGrid User Guide
80
Read Discrete Inputs
Request Size Value
Function Code 1 Byte 0x02
Starting Address 2 Bytes 0x0000 to 0xFFFF
Quantity of Inputs 2 Bytes 0x0000 to 0x07D0 (1 to 2000)
Response Size Value
Function Code 1 Byte 0x02
Byte Count 1 Byte N*
Input Status N* x 1 Byte
N* = Quantity of Inputs / 8, if the remainder is different of 0

N = N + 1
Error Size Value
Error Code 1 Byte Function Code + 0x80 = 0x82
Exception Code 1 Byte 0x01, 0x02, 0x03 , 0x04
Read Holding Registers Format
Request Size Value
Function Code 1 Byte 0x03
Starting Address 2 Bytes 0x0000 to 0xFFFF
Quantity of Registers 2 Bytes 0x0001 to 0x007D (1 to 125)
Response Size Value
Function Code 1 Byte 0x03
Byte Count 1 Byte 2 x N*
Register Value N* x 2 Bytes
N* = Quantity of Registers
Error Size Value
Error Code 1 Byte Function Code + 0x80 = 0x83
Exception Code 1 Byte 0x01, 0x02, 0x03 , 0x04