Siemens Simatic M7-400 Reference Manual page 513

13.5.1 Pin Assignments
X1 Socket
Table 13-15
Pin
1 /STROBE
2 Data 0
3 Data 1
4 Data 2
5 Data 3
6 Data 4
7 Data 5
8 Data 6
9 Data 7
10 /ACK
11 BUSY
12 PE
13 SLCT
14 /AUTO FEED
15 /ERROR
16 /RESET
17 /SLCT IN
18 GND
19 GND
: GND
24 GND
25 GND
Note
Operational ground (GND signal) at the COMa or COMb ports is referenced to
internal ground.
Suitable measures may be required on the process side to avoid ground loops.
S7-400, M7-400 Programmable Controllers Module Specifications
A5E00069467-07
Socket X1, IF 962-LPT (25-Pin Sub D Socket Connector)
Meaning
Interface Submodules
Direction
Input/output
Input/output
Input/output
Input/output
Input/output
Input/output
Input/output
Input/output
Input/output
Input
Input
Input
Input
Output
Input
Output
Output
–
–
–
–
–
13-17