Functions/operations using PROFIBUS PA
11.3 Cyclic data transfer
SIPART PS2 with PROFIBUS communication
194
Operating Instructions, 09/2007, A5E00127926-07
Figure 11-4 STEP 7 sample program
In this example, all data in the input and output directions supported by the device are
transferred. The selected peripheral starting address is 256 (W#16#100).
Note
Only the older SIMATIC CPUs require the SFC14 and SFC16 modules for consistent
reading and writing.
Legend of the sample program
Byte
Function
Composition
Number of bytes
READBACK
5
RCAS_OUT
5
CHECKBACK
3
Byte 15
Input data
POS_D
2
SP
5
Byte 10
Output data
RCAS_IN
5