Welcome to Serial communication module repository
1. Serial communication module interface distribution
Serial communication module interface distribution
Module front
| Serial Number | name | introduce | Remark |
|---|---|---|---|
| ① | USB Type-C interface | USB power supply and communication interface | Can be inserted in either direction |
| ② | TTL voltage selection switch | Three-position switch: Left: 1.8V; Middle: 3.3V; Right: 5V | USB-TTL mode and TTL-485 mode are valid. |
| ③ | Operating mode selection switch | Three-position switch: Left: TTL-485: TTL to RS485 mode; Middle: USB-RS485: USB to RS485 mode; Right: USB-TTL: USB to TTL mode. | Only one mode can be run at a time; simultaneous operation is not possible. |
| ④ | 5V | 5V voltage output interface (maximum output current not exceeding 300mA) | The module can be powered by an external 5V supply; do not power it simultaneously with the USB port. This is unrelated to the TTL voltage selection switch. |
| ④ | GND | power ground | |
| ④ | RXD | TTL mode data receive pin | Connect to the TXD pin of an external device |
| ④ | TXD | TTL mode transmit data pin | Connect to the RXD pin of an external device |
| ④ | RTS | Request Send Pin | |
| ④ | CTS | Clear transmit pin |
reverse side
| Serial Number | name | introduce | Remark |
|---|---|---|---|
| ① | 3V3 | 3.3V voltage output interface (maximum output current not exceeding 300mA) | It is independent of TTL voltage selection switches. |
| ① | GND | power ground | |
| ① | 485-B | Pin B in RS485 mode | |
| ① | 485-A | Pin A in RS485 mode | |
| ① | GND | power ground | |
| ① | 1V8 | 1.8V voltage output interface (maximum current not exceeding 300mA) | It is independent of TTL voltage selection switches. |