GW-7553-B / GW-7553-M PROFIBUS/Modbus TCP Gateway User Manual
(Version 1.35, May/2017)
PAGE: 92
PS:
Modbus command:
Query message
DA
FC
SA
(Hi)
SA
(Lo)
NO
(Hi)
NO
(Lo)
01
02
00
00
00
10
Response message
DA
FC
BC
DATA
01
02
02
FE
DC
DA: Device Address-0x01
FC: Function Code-0x02:read DI
SA(Hi): Start Address(Hi byte)-0x00
SA(Lo): Start Address(Lo byte)-0x00
NO(Hi): No. Of points(Hi byte)-0x00
NO(Lo): No. Of points (Lo byte)-0x10
BC: Byte Count-0x02