B&B Electronics GW-7553 - Manual - Manual (Page 48)

Figure 45 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)
CRC
check
01 02 00 00 00 10 79 C6
Response message
DA FC BC DATA
CRC
check
01 02 02 FE DC F8 41
GW-7553 PROFIBUS/Modbus TCP Gateway User Manual (Version 1.00, Dec/2008) PAGE: 48