# 시리얼 포트 매핑

This topic shows how to determine the mapping between USART/UART serial port device names (e.g. "ttyS0") and the associated ports on a flight controller, such as `TELEM1`, `TELEM2`, `GPS1`, `RC SBUS`, `Debug console`.

The instructions are used to generate serial port mapping tables in flight controller documentation.
For example: [Pixhawk 4 > Serial Port Mapping](../flight_controller/pixhawk4.md#serial-port-mapping).

:::info
The function assigned to each port does not _have to_ match the name (in most cases), and is set using a [Serial Port Configuration](../peripherals/serial_configuration.md).
Usually the port function is configured to match the name, which is why the port labelled `GPS1` will work with a GPS out of the box.
:::

## STMxxyyy의 NuttX

<!-- instructions from DavidS here: https://github.com/PX4/PX4-user_guide/pull/672#issuecomment-598198434 -->

보드 설정 파일을 검사하여 STMxxyyy 아키텍처에서 NuttX 빌드에 대한 매핑 획득 방법을 설명합니다.
FMUv5를 사용하지만, 다른 FMU 버전/NuttX 보드에도 유사하게 확장할 수 있습니다.

### default.cmake

The **default.px4board** lists a number of serial port mappings (search for the text "SERIAL_PORTS").

From [/boards/px4/fmu-v5/default.px4board](https://github.com/PX4/PX4-Autopilot/blob/main/boards/px4/fmu-v5/default.px4board):

```
SERIAL_PORTS
    GPS1:/dev/ttyS0
    TEL1:/dev/ttyS1
    TEL2:/dev/ttyS2
    TEL4:/dev/ttyS3
```

Alternatively you can launch boardconfig using `make px4_fmu-v5 boardconfig` and access the serial port menu

```
    Serial ports  --->
        (/dev/ttyS0) GPS1 tty port
        ()  GPS2 tty port
        ()  GPS3 tty port
        ()  GPS4 tty port
        ()  GPS5 tty port
        (/dev/ttyS1) TEL1 tty port
        (/dev/ttyS2) TEL2 tty port
        ()  TEL3 tty port
        (/dev/ttyS3) TEL4 tty port
        ()  TEL5 tty port
```

### nsh/defconfig

The _nsh/defconfig_ allows you to determine which ports are defined, whether they are UART or USARTs, and the mapping between USART/UART and device.
You can also determine which port is used for the [serial/debug console](../debug/system_console.md).

Open the board's defconfig file, for example: [/boards/px4/fmu-v5/nuttx-config/nsh/defconfig](https://github.com/PX4/PX4-Autopilot/blob/main/boards/px4/fmu-v5/nuttx-config/nsh/defconfig#L215-L221)

Search for the text "ART" until you find a section like with entries formatted like `CONFIG_STM32xx_USARTn=y` (where `xx` is a processor type and `n` is a port number).
예:

```
ttyS0 CONFIG_STM32F7_USART1=y
ttyS1 CONFIG_STM32F7_USART2=y
ttyS2 CONFIG_STM32F7_USART3=y
ttyS3 CONFIG_STM32F7_UART4=y
ttyS4 CONFIG_STM32F7_USART6=y
ttyS5 CONFIG_STM32F7_UART7=y
ttyS6 CONFIG_STM32F7_UART8=y
```

The entries tell you which ports are defined, and whether they are UART or USART.

DEBUG 콘솔 매핑을 가져오기 위해 <code>SERIAL_CONSOLE</code>에 대한 <a href="https://github.com/PX4/PX4-Autopilot/blob/master/boards/px4/fmu-v5/nuttx-config/nsh/defconfig#L212">defconfig 파일</a>을 검색합니다.
Increment the device number _ttyS**n**_ alongside (zero based) to get the device-to-serial-port mapping.

```
CONFIG_UART7_SERIAL_CONSOLE=y
```

To get the DEBUG console mapping we search the [defconfig file](https://github.com/PX4/PX4-Autopilot/blob/main/boards/px4/fmu-v5/nuttx-config/nsh/defconfig#L212) for `SERIAL_CONSOLE`.
Below we see that the console is on UART7:

```
#define PX4IO_SERIAL_DEVICE            "/dev/ttyS6"
#define PX4IO_SERIAL_TX_GPIO           GPIO_UART8_TX
#define PX4IO_SERIAL_RX_GPIO           GPIO_UART8_RX
#define PX4IO_SERIAL_BASE              STM32_UART8_BASE
```

### board_config.h

For flight controllers that have an IO board, determine the PX4IO connection from **board_config.h** by searching for `PX4IO_SERIAL_DEVICE`.

For example, [/boards/px4/fmu-v5/src/board_config.h](https://github.com/PX4/PX4-Autopilot/blob/main/boards/px4/fmu-v5/src/board_config.h#L59):

```
ttyS0 CONFIG_STM32F7_USART1=y GPS1
ttyS1 CONFIG_STM32F7_USART2=y TEL1
ttyS2 CONFIG_STM32F7_USART3=y TEL2
ttyS3 CONFIG_STM32F7_UART4=y TEL4
ttyS4 CONFIG_STM32F7_USART6=y
ttyS5 CONFIG_STM32F7_UART7=y DEBUG
ttyS6 CONFIG_STM32F7_UART8=y PX4IO
```

So the PX4IO is on `ttyS6` (we can also see that this maps to UART8, which we already knew from the preceding section).

### 결합

<a href="../flight_controller/pixhawk4.md#serial-port-mapping">비행 콘트롤러 문서</a>의 결과 표는 다음과 같습니다.

```
ttyS0 CONFIG_STM32F7_USART1=y GPS1
ttyS1 CONFIG_STM32F7_USART2=y TEL1
ttyS2 CONFIG_STM32F7_USART3=y TEL2
ttyS3 CONFIG_STM32F7_UART4=y TEL4
ttyS4 CONFIG_STM32F7_USART6=y
ttyS5 CONFIG_STM32F7_UART7=y DEBUG
ttyS6 CONFIG_STM32F7_UART8=y PX4IO
```

In the [flight controller docs](../flight_controller/pixhawk4.md#serial-port-mapping) the resulting table is:

| UART   | 장치         | 포트                                |
| ------ | ---------- | --------------------------------- |
| UART1  | /dev/ttyS0 | GPS                               |
| USART2 | /dev/ttyS1 | TELEM1 (흐름 제어) |
| USART3 | /dev/ttyS2 | TELEM2 (흐름 제어) |
| UART4  | /dev/ttyS3 | TELEM4                            |
| USART6 | /dev/ttyS4 | RC SBUS                           |
| UART7  | /dev/ttyS5 | 디버그 콘솔                            |
| UART8  | /dev/ttyS6 | PX4IO                             |

## 기타 아키텍처

:::info
Contributions welcome!
:::

## See Also

- [Serial Port Configuration](../peripherals/serial_configuration.md)
- [MAVLink Telemetry (OSD/GCS)](../peripherals/mavlink_peripherals.md)