Siemens SIMATIC S7-1500 Manual page 25

When you use the "24 V, asymmetrical" signal interface, you have the following possible
combinations for the named functions:
Table 3- 3
Technology Module TM PTO 4 (6ES7553-1AA00-0AB0)
Manual, 12/2016, A5E38896703-AA
Possible combinations for "24 V, asymmetrical" signal interface
DIn.0 DIn.1
— —
RS —
— —
RS —
— —
RS —
RS MI
RS MI
RS MI
— MI
— MI
— MI
DR —
DR —
DR MI
DR MI
— DR
— DR
RS DR
RS DR
DIQn.2
Input Output
— —
— —
DR —
DR —
— ED
— ED
— —
DR —
— ED
— —
DR —
— ED
— —
— ED
— —
— ED
— —
— ED
— —
— ED
Connecting
3.1 Pin assignment
DQn.0 DQn.1
P/A signal D/B signal
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