B&B Electronics GW-7553 - Manual - Manual (Page 16)

GW-7553 PROFIBUS/Modbus TCP Gateway User Manual (Version 1.00, Dec/2008) PAGE: 16
3. Communication protocol transfer theorem
3.1 PROFIBUS data exchange
The GW-7553 is a PROFIBUS DP Slave device. The GW-7553 is first
parameterized then configured and finally it goes into the data exchange mode
(Figure 11).
Figure 11 State machine of PROFIBUS DP Slave device
The GW-7553 exchanges data cyclically between internal DI、DO、AI、AO
data and PROFIBUS Master device in data exchange mode, as shown in figure 12.