Siemens Simatic box pc 627b Operating Instructions Manual page 127

Serial port COM1, X135
The COM1 serial port has the following pin assignment:
Serial interface COM1
PinNo.
1
2
3
4
5
6
7
8
9
SIMATIC Box PC 627
Operating Instructions, Release 05/2006, A5E00362052-03
Abbreviation Meaning
DCD (M5) Receiving signal level carrier
RxD (D2) Received data
TxD (D1) Transmitted data
DTR (S1) Data terminal ready
GND (E2) Functional ground (reference potential) –
DSR (M1) Ready for operation
RTS (S2) Request to send
CTS (M2) Clear to send
RI (M3) Incoming call
Detailed descriptions
16.1 Motherboard
Input /Output
Input
Input
Output
Output
Input
Output
Input
Input
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