10
DB25 Pin Description
The FASTCOM: 232/4-LPCI-335 features four RS-232 channels, which are accessed through four DB25
connectors on the cable assembly.
The following is a pin description of the DB25 connectors:
PIN NO.
SIGNAL NAME
DIRECTION
1 No
Connect
2 TRANSMIT
DATA
(TxD)
OUTPUT
3
RECEIVE DATA (RxD)
INPUT
4
REQUEST TO SEND (RTS)
OUTPUT
5
CLEAR TO SEND (CTS)
INPUT
6
DATA SET READY (DSR)
INPUT
7
SIGNAL GROUND (GND)
GROUND
8
CARRIER DETECT (CD)
INPUT
9 – 19
No Connect
20
DATA TERMINAL READY (DTR) OUTPUT
21 No
Connect
22
RING INDICATOR (RI)
INPUT
23-25 No
Connect