> For the complete documentation index, see [llms.txt](https://docs.arkelectron.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.arkelectron.com/products/flight-controller/arkv6x/ardupilot-instructions.md).

# ArduPilot Instructions

{% embed url="<https://ardupilot.org/copter/docs/common-ark-v6x-overview.html>" %}
ARKV6X ArduPilot Documentation
{% endembed %}

To build or flash ArduPilot, see [Firmware](/products/flight-controller/arkv6x/firmware.md#ardupilot).

## Serial Port Mapping

{% hint style="info" %}
Serial Port Mapping for Default Firmware with No IOMCU
{% endhint %}

| **UART** | **Serial Number** | **Port**      |
| -------- | ----------------- | ------------- |
| UART7    | SERIAL1           | TELEM1        |
| UART5    | SERIAL2           | TELEM2        |
| USART1   | SERIAL3           | GPS           |
| UART8    | SERIAL4           | GPS2          |
| USART2   | SERIAL5           | TELEM3        |
| UART4    | SERIAL6           | UART4 & I2C   |
| USART3   | SERIAL7           | Debug Console |
| USART6   | SERIAL8           | PX4IO/RC      |

## hwdef modifications for use with an IOMCU

The default build is for a carrier without an IOMCU, such as the ARK PAB Carrier, where USART6 is the RC input. For a carrier with an IOMCU on USART6, edit the [ARKV6X hwdef](https://github.com/ArduPilot/ardupilot/blob/Copter-4.7.1/libraries/AP_HAL_ChibiOS/hwdef/ARKV6X/hwdef.dat) and build it:

1. Swap the `SERIAL_ORDER` line comments ([L30-L33](https://github.com/ArduPilot/ardupilot/blob/Copter-4.7.1/libraries/AP_HAL_ChibiOS/hwdef/ARKV6X/hwdef.dat#L30-L33)) to remove USART6 from the serial ports.
2. Comment out `define DEFAULT_SERIAL8_PROTOCOL SerialProtocol_RCIN` ([L88](https://github.com/ArduPilot/ardupilot/blob/Copter-4.7.1/libraries/AP_HAL_ChibiOS/hwdef/ARKV6X/hwdef.dat#L88)), present from ArduPilot 4.7.0. With USART6 removed, SERIAL8 is the second USB port.
3. Uncomment `IOMCU_UART USART6` ([L91](https://github.com/ArduPilot/ardupilot/blob/Copter-4.7.1/libraries/AP_HAL_ChibiOS/hwdef/ARKV6X/hwdef.dat#L91)).

Keep the `PC6` and `PC7` USART6 pin lines; the IOMCU uses them.

Build and flash the firmware using the steps in [Firmware](/products/flight-controller/arkv6x/firmware.md#ardupilot).


---

# Agent Instructions
This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com.

## Querying This Documentation
If you need additional information that is not directly available in this page, you can query the documentation by asking a question.

Perform an HTTP GET request on the following URL with the `ask` and `goal` query parameters:

```
GET https://docs.arkelectron.com/products/flight-controller/arkv6x/ardupilot-instructions.md?ask=<question>&goal=<user_goal>
```

`ask` is the immediate question: it should be specific, self-contained, and written in natural language.
`goal` is what the user is ultimately trying to achieve, the reason they need the answer. Sharing it helps GitBook give you a better, more relevant answer. A goal is most helpful when it describes the outcome the user wants rather than restating the question. For example, with `ask=how do I create an API token`, a goal like `automate deployments from our CI pipeline` lets GitBook tailor the answer to that use case.

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.