LS Industrial Systems XGB Series - Page 29

Chapter 5 Protocols of Various Services
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(c) Error
Classification Size Range
Function code 1 byte 0x81 (Function code + 0x80)
Exception code 1 byte 0x01,0x02,0x03,0x04
[Table 5-15] Function code 0x01 error frame
(d) Examples
Request frame Response frame
Classification HEX Classification HEX
Function code 0x01 Function code 0x01
Start address (Upper byte) 0x00 Number of bytes 0x03
Start address (Lower byte) 0x13 Coil status (27-20) 0xCD
Number of coils (Upper byte) 0x00 Coil status (36-28) 0x6B
Number of coils (Lower byte) 0x13 Coil status (38-36) 0x05
[Table 5-16] Function code 0x01 frame examples
(2) Function code 0x02: Read input bit (Read Discrete Inputs)
(a) Request
Classification Size Range
Function code 1 byte 0x02
Start address 2 bytes 0x0000 ~ 0xFFFF
Number of input 2 bytes 0x0001 ~ 0x07D0 (2000 bits)
[Table 5-17] Function code 0x02 request frame
(b) Response
Classification Size Range
Function code 1 byte 0x01
Number of bytes 2 bytes N
Input status N x 1 bytes -
[Table 5-18] Function code 0x02 response frame
(c) Error
Classification Size Range
Function code 1 byte 0x82 (Function code + 0x80)
Exception code 1 bytes 0x01,0x02,0x03,0x04
[Table 5-19] Function code 0x02 response frame
(d) Examples
Request frame Response frame
Classification HEX Classification HEX
Function code 0x02 Function code 0x01
Start address (Upper byte) 0x00 Number of bytes 0x03
Start address (Lower byte) 0xC4 Coil status (27-20) 0xCD
Input status (Upper byte) 0x00 Coil status (36-28) 0x6B
Number of coils (Lower byte) 0x16 Coil status (38-36) 0x05
[Table 5-20] Function code 0x02 request frame examples