RJ45 - RS232
Converters fit, for example, printers and PC.
Cables adapters are usually powered by the external 5V and convert RS232 RJ45 signals.
The tables below give the wiring :
RJ45 to RS232 schemas :
| RJ45 | ----------------------------- | DB25 |
|---|---|---|
| 4 (TXD) | ----------------------------- | 3 (RXD) |
| 5 (RXD) | ----------------------------- | 2 (TXD) |
| 6 (GND) | ----------------------------- | 7 (GND) |
| RJ45 | ---------------- | DB25 |
|---|---|---|
| 4 (TXD) | ---------------- | 3 (RXD) |
| 5 (RXD) | ---------------- | 2 (TXD) |
| 6 (GND) | ---------------- | 7 (GND) |
| 7 (CTS) | ---------------- | 20 (DTR) |
The most common protocols are supported by the converters, including TCP - IP for Windows.
The port must be set to optimize the speed of communication, otherwise it can be slow.
These adapters are cheap. We find them for sale on many web sites.
| RJ45 | ----------------------------- | PC DB25 |
|---|---|---|
| 3 (DSR) | ----------------------------- | 20 (DTR) |
| 2 (RTS) | ----------------------------- | 5 (CTS) |
| 4 (TXD) | ----------------------------- | 3 (RXD) |
| 5 (RXD) | ----------------------------- | 2 (TXD) |
| 6 (GND) | ----------------------------- | 7 (GND) |
| 7 (CTS) | ----------------------------- | 4 (RTS) |
| 8 (DTR) | ----------------------------- | 6 (DSR) |
| RJ45 | ----------------------------- | PC DB9 |
|---|---|---|
| 3 (DSR) | ----------------------------- | 4 (DTR) |
| 2 (RTS) | ------------------------------ | 8 (CTS) |
| 4 (TXD) | ------------------------------ | 2 (RXD) |
| 5 (RXD) | ------------------------------ | 3 (TXD) |
| 6 (GND) | ------------------------------- | 5 (GND) |
| 7 (CTS) | ------------------------------ | 7 (RTS) |
| 8 (DTR) | ------------------------------- | 6 (DSR) |
Example of a converter card.