B&B Electronics GW-7553 - Manual - Manual (Page 58)

Figure 58 Send Modbus command to read DI of the GW-7553 and
receive data (0xFE, 0xDC)
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
GW-7553 PROFIBUS/Modbus TCP Gateway User Manual (Version 1.00, Dec/2008) PAGE: 58