B&B Electronics GW-7553 - Manual - Manual (Page 55)

GW-7553 PROFIBUS/Modbus TCP Gateway User Manual (Version 1.00, Dec/2008) PAGE: 55
Table 16 Receive “0xFF” in the input data area
Module Byte Data type Representation Value
Input 0 Byte Hex 0xFF
Input module
Input 1 Byte Hex 0xFF
PS:
Modbus command:
Query message
DA FC
SA
(Hi)
SA
(Lo)
NO
(Hi)
NO
(Lo)
BC DATA
01 0F 00 00 00 10 02 FF FF
Response message
DA FC
SA
(Hi)
SA
(Lo)
NO
(Hi)
NO
(Lo)
01 0F 00 00 00 10
z DA: Device Address-0x01
z FC: Function Code-0x0F=>Write multi-DO
z SA(Hi): Start Address(Hi byte)-0x00
z SA(Lo): Start Address(Lo byte)-0x00
z NO(Hi): No. Of points (Hi byte)-0x00
z NO(Lo): No. Of points (Lo byte)-0x10
z BC: Byte Count-0x02
4.9.2 Receiving data from the PROFIBUS Master device
--Send Command to read DI of the GW-7553
The user needs to input command (” 01 02 00 00 00 10”) in MBTCP and click
button to send Modbus command: “01 02 00 00 00 10”
and then MBTCP can receive response message (” 01 02 02 00 00”). In this