| Pinout for:RS232 25 pin |
Description : RS-232 was created for one purpose, to interface between Data Terminal Equipment (DTE) and Data Communications Equipment (DCE) employing serial binary data interchange. So as stated the DTE is the terminal or computer and the DCE is the modem or other communications device.
At the DTE
At the DCE
Pinout :
| Pin | Name | Description |
| 1 | GND | AA: Protective Ground |
| 2 | TXD | BA: Transmit Data |
| 3 | RXD | BB: Receive Data |
| 4 | RTS | CA: Request to Send |
| 5 | CTS | CB: Clear to Send |
| 6 | DSR | CC: Data Set Ready |
| 7 | GND | AB: Signal Ground |
| 8 | CD | CF: Carrier Detect |
| 9 | - | RESERVED - Positive test |
| 10 | - | RESERVED - Negative test |
| 11 | STF | Select Transmit Channel |
| 12 | S.CD | SCF: Secondary Carrier Detect |
| 13 | S.CTS | SCB: Secondary Clear to Send |
| 14 | S.TXD | SBA: Secondary Transmit Data |
| 15 | TCK | DB: Transmission Signal Element Timing |
| 16 | S.RXD | SBB: Secondary Receive Data |
| 17 | RCK | DD: Receiver Signal Element Timing |
| 18 | LL | Local Loop Control |
| 19 | S.RTS | SCA: Secondary Request to Send |
| 20 | DTR | CD: Data Terminal Ready |
| 21 | RL | Remote Loop Control |
| 22 | RI | CE: Ring Indicator |
| 23 | DSR | CH/CI: Data Signal Rate Selector |
| 24 | XCK | DA: Transmit Signal Element Timing |
| 25 | TI | Test Indicator |
Note : RS232 25 pin