---
id: rak-gpio-mapping
title: RAK GPIO Pin Mapping
sidebar_label: RAK GPIO Mapping
sidebar_position: 5
---

## RAK GPIO Pin Mapping

The RAK4631 uses symbolic labels for its I/O Pins on the module and baseboard silk screens. The following table shows the mapping of the RAK4631 GPIO pins to the corresponding Arduino pins and the MCU Port numbers.

| RAK Pin | nRF52840 Pin | Arduino GPIO | Remark |
| ------- | ------------ | ------------ | ------ |
| IO1 | P0.17 | 17 | used for GPS PPM signal if GPS module is connected |
| IO2 | P1.02 | 34 | used to power all peripheral modules, not available for user application |
| IO3 | P0.21 | 21 |
| IO4 | P0.04 | 4 |
| IO5 | P0.09 | 9 | The 'User Button' is mapped here. |
| IO6 | P0.10 | 10 |
| IO7 | P0.28 | 28 |
| SW1 | P0.01 | 1 |
| A0  | P0.04/AIN2 | A2 |
| A1  | P0.31/AIN7 | A7 |
| SPI_CS | P0.26 | 26 |

When configuring GPIO pins in your device settings, the Arduino GPIO numbers should be used.

```shell title="Example"
meshtastic --set external_notification.output 10
```
This will use IO6 on a RAK4631

:::caution Note
There is no usable GPIO pin on any RAK base board except the 'big' baseboard RAK19001 without adding a RAK13002 IO module or a third party IO sensor breakout.
:::