RS485 board is center with a red arrow pointing to it.
## Overview
The [RS485](https://en.wikipedia.org/wiki/RS-485) board enables serial communication between the [Raspberry Pi](https://khalil-lab.gitbook.io/evolver/hardware/raspberry-pi) (server) and the [Arduinos ](https://khalil-lab.gitbook.io/evolver/hardware/motherboard-layout-and-circuitry/arduino)(controlling the parameters).
## Troubleshooting
The RS485 board has broken on very rare occasions.
### Symptoms
No communication between all Arduinos and the Raspberry Pi server
### Diagnosis
If only one Arduino is not communicating More likely to be something wrong with:
1. Arduino
2. [Motherboard](https://khalil-lab.gitbook.io/evolver/troubleshooting/vial-platform-troubleshooting/motherboard-troubleshooting-replacement) connections between Arduino and RS485 board
If you have tried a new Arduino with new code and verified motherboard connections work, it may be the RS485 board itself. Try a new RS485 board ordered from Fynch.
---
# Agent Instructions: Querying This Documentation
If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.
Perform an HTTP GET request on the current page URL with the `ask` query parameter:
```
GET https://khalil-lab.gitbook.io/evolver/hardware/motherboard-layout-and-circuitry/rs485-board.md?ask=
```
The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.
Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.
