SMC Networks 48-Port - Manual (Page 56)

C
ABLES
B-6
DB-9 Port Pin Assignments
Console Port to 9-Pin COM Port on PC
Console Port to 25-Pin DCE Port on Modem
EIA
Circuit
CCITT
Signal Description Switch’s
DB9 DTE
Pin #
PC DB9
DTE
Pin #
Modem
DB25
DCE Pin #
Signal
Direction
DTE-DCE
CF 109 DCD (Data Carrier Detected) 1 1 8 <------
BB 104 RxD (Received Data) 2 2 3 <------
BA 103 TxD (Transmitted Data) 3 3 2 ------>
CD 108.2 DTR (Data Terminal Ready) 4 4 20 ------>
AB 102 SG (Signal Ground) 5 5 7 -------
CC 107 DSR (Data Set Ready) 6 6 6 <------
CA 105 RTS (Request-to-Send) 7 7 4 ------>
CB 106 CTS (Clear-to-Send) 8 8 5 <------
CE 125 RI (Ring Indicator) 9 9 22 <------
Switch’s 9-Pin
Serial Port
CCITT Signal PC’s 9-Pin
COM Port
1 DCD ----------- DCD ------------ 1
2 RXD <--------- TXD ------------ 3
3 TXD ----------- RXD ----------> 2
4 DTR ----------- DSR ----------> 6
5 SGND ----------- SGND ---------- 5
6 DSR ----------- DTR ------------ 4
7 RTS ----------- CTS -----------> 8
8 CTS <--------- RTS ------------- 7
9 RI ----------- RI --------------- 9
Switch’s 9-Pin
Serial Port
CCITT Signal Modem’s 25-Pin
DCE Port
1 <--------- DCD ------------ 8
2 <--------- RXD ------------ 3
3 ----------- TXD ----------> 2
4 ----------- DTR ----------> 20
5 ----------- SGND ---------- 7
6 <--------- DSR ------------ 6
7 ----------- RTS -----------> 4
8 <--------- CTS ------------- 5
9 <--------- RI --------------- 22