3. Communication protocol transfer theorem
3.1 PROFIBUS data exchange
The GW-7557 is a PROFIBUS DP slave device. The GW-7557 is first
parameterized then configured and finally it goes into the data exchange mode
(
Figure 15
).
Figure 15 State machine of PROFIBUS DP Slave device
The GW-7557 exchanges data cyclically between internal Output Queue
、
Input
Queue and PROFIBUS Master device in data exchange mode, as shown in
Figure
16
.
GW-7557 PROFIBUS/HART Gateway User Manual
(Version 1.00, Dec/2011)
PAGE: 18
