I'm working currently on a professional RS422/RS485 shield for the Arduino UNO (and compatible boards) and other SBC with Arduino style headers (like STM Nucleo) . I wasn't satisfied with the shields on the market. They are very simple and have some disadvantages. My shield comes with the following features:
- RS485 mode (half duplex)
- RS422 mode (full duplex)
- galvanic isolation between Arduino and connected RS485 bus
- free choice of TX-pin between pins 0-5
- free choice of RX-pin between pins 0-5
- enhanced ESD protection
- adjustable automatic transceiver switching for RS485 mode
- adjustable control of transceiver/receiver via pin 6 or 7
- adjustable Pull-Up, Pull-Down und terminating resistors
- indicator LEDs for RX and TX
- removable block terminal for bus connection
- many options adjustable via DIP switches
- stackable headers
- can be configured for 3.3V and 5V logic
Details
Files
Arduino_RS485 Shield schematic V01-01-00.pdf
Adobe Portable Document Format -
210.13 kB -
08/14/2018 at 08:58
A new tutorial is available at Arduino.cc and Instructables.com. How to use industrial encoders with RS422 output with Arduino and our Arduino RS422 shield:
Test run of a RS485 connection of a Raspberry Pi (left position), Arduino 101 and Arduino UNO (right).... This setting can be extended to up to 255 devices and a distance over 1km