Siemens CPU 31 Series Technical Data Manual page 151

Figure 6-7
Parameters of standard DO
There are no parameters for standard digital outputs.
CPU 31xC and CPU 31x, Technical Data
Manual, 01/2006 Edition, A5E00105475-06
Structure of record 1 for standard DI and interrupt inputs (length of 10 bytes)
Technical data of CPU 31xC
6.6 Technical data of the integrated I/O
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