- RS232 Pinout, Direction & signal Levels -
| EIA-232-E (RS-232)
FUNCTION |
Pin #
DB-25 |
Pin #
DB-9 |
EIA-530
FUNCTION |
Pin #
DB-25 |
TO
DTE |
TO
DCE |
| Shield | 1 | Shield | 1 |
| Transmit Data (TD) | 2 | 3 | Transmit Data (A)
(B) |
2
14 |
> |
| Receive Data (RD) | 3 | 2 | Receive Data (A)
(B) |
3
16 |
< |
| Request To Send (RTS) | 4 | 7 | Request To Send (A)
(B) |
4
19 |
> |
| Clear To Send (CTS) | 5 | 8 | Clear To Send (A)
(B) |
5
13 |
< |
| DCE Ready (DSR) | 6 | 6 | DCE Ready (A)
(B) |
6
22 |
< |
| Signal Ground (SG) | 7 | 5 | Signal Ground (A) | 7 |
| Received Line Signal Detector (DCD) | 8 | 1 | Received Line (A)
Signal Detector (B) |
8
10 |
< |
| DTE Ready (DTR) | 20 | 4 | DTE Ready (A)
(B) |
20
23 |
> |
| Ring Indicator (RI) | 22 | 9 | N/A | - |
|
|
|
| Signal with respect to SG | Signal A with respect to Signal B |
| RS-232 | RS-422 | RS-485 | |
| "0", Asserted, ON, Space, Active | +3 to +25 VDC | +2 to +6 VDC (Trasmit)
+0.2 to +7 VDC (Receive) |
+1.5 to +6 VDC (Transmit)
+0.2 to +12 VDC (Receive) |
| "1", Desasserted, OFF, Mark, Inactive | -3 to -25 VDC | -2 to +6 VDC (Transmit)
-0.2 to -7 VDC (Receive) |
-1.5 to -6 VDC (Transmit)
-0.2 to -7 VDC (Receive) |
Copyright © 2002-2008 Ted J. Mieske
All Rights Reserved.