Rs 485 - Getting started
Arduino library
To test the RS-485 Transceiver Breakout Board with Arduino, you can use the HardwareSerial library, which is built into the Arduino IDE and does not require additional installation. Since RS-485 communication uses differential signals, this example is sufficient to showcase its functionality.
First time Arduino user? For a detailed tutorial on how to get started with Arduino, see this section of our docs:
Getting started with Arduino
A full, comprehensive tutorial on how to fully set up and upload code for the first time on an Arduino board, from scratch!
Connections
Below is an example connection diagram for Dasduino CONNECTPLUS and the RS-485 Transceiver Breakout Board. These pins will be used in the examples throughout this documentation.
| Dasduino CONNECTPLUS | RS-485 Breakout Board |
|---|---|
| IO13 (TX)(*User Choice) | D (Driver Input) |
| IO14 (RX)(*User Choice) | R (Receiver Output) |
| IO12 (DE) | DE (Driver Enable) |
| IO2 (NRE) | NRE (Receiver Enable) |
| 5V | VCC |
| GND | GND |
| A | RS-485 Bus Line A |
| B | RS-485 Bus Line B |
If your RS-485 breakout board is at one end of the bus, close jumper JP2 to enable the termination resistor. If it’s not at an endpoint, leave JP2 open.
If you prefer, you can use a second RS-485 channel for additional communication:
| Dasduino CONNECTPLUS | RS-485 Breakout Board |
|---|---|
| IO27 (TX)(*User Choice) | D (Driver Input) |
| IO26 (RX)(*User Choice) | R (Receiver Output) |
| IO25 (DE) | DE (Driver Enable) |
| IO24 (NRE) | NRE (Receiver Enable) |
| 5V | VCC |
| GND | GND |
| A | RS-485 Bus Line A |
| B | RS-485 Bus Line B |