> For the complete documentation index, see [llms.txt](https://ykkim.gitbook.io/ec/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://ykkim.gitbook.io/ec/stm32-m4-programming/mbed-os.md).

# mbed OS

## API List

[Full API list for mbed](https://os.mbed.com/docs/mbed-os/v6.13/apis/index.html)

#### Serial (UART) drivers

| API                                                                                   | Full profile | Bare metal profile |
| ------------------------------------------------------------------------------------- | ------------ | ------------------ |
| [BufferedSerial](https://os.mbed.com/docs/mbed-os/v6.13/apis/serial-uart-apis.html)   | ✔            | ✔                  |
| [UnbufferedSerial](https://os.mbed.com/docs/mbed-os/v6.13/apis/unbufferedserial.html) | ✔            | ✔                  |

#### SPI drivers

| API                                                                         | Full profile | Bare metal profile |
| --------------------------------------------------------------------------- | ------------ | ------------------ |
| [QuadSPI (QSPI)](https://os.mbed.com/docs/mbed-os/v6.13/apis/spi-apis.html) | ✔            | ✔                  |
| [SPI](https://os.mbed.com/docs/mbed-os/v6.13/apis/spi.html)                 | ✔            | ✔                  |
| [SPISlave](https://os.mbed.com/docs/mbed-os/v6.13/apis/spislave.html)       | ✔            | ✔                  |

#### Input/Output drivers

| API                                                                           | Full profile | Bare metal profile |
| ----------------------------------------------------------------------------- | ------------ | ------------------ |
| [AnalogIn](https://os.mbed.com/docs/mbed-os/v6.13/apis/i-o-apis.html)         | ✔            | ✔                  |
| [AnalogOut](https://os.mbed.com/docs/mbed-os/v6.13/apis/analogout.html)       | ✔            | ✔                  |
| [BusIn](https://os.mbed.com/docs/mbed-os/v6.13/apis/busin.html)               | ✔            | ✔                  |
| [BusOut](https://os.mbed.com/docs/mbed-os/v6.13/apis/busout.html)             | ✔            | ✔                  |
| [BusInOut](https://os.mbed.com/docs/mbed-os/v6.13/apis/businout.html)         | ✔            | ✔                  |
| [DigitalIn](https://os.mbed.com/docs/mbed-os/v6.13/apis/digitalin.html)       | ✔            | ✔                  |
| [DigitalOut](https://os.mbed.com/docs/mbed-os/v6.13/apis/digitalout.html)     | ✔            | ✔                  |
| [DigitalInOut](https://os.mbed.com/docs/mbed-os/v6.13/apis/digitalinout.html) | ✔            | ✔                  |
| [InterruptIn](https://os.mbed.com/docs/mbed-os/v6.13/apis/interruptin.html)   | ✔            | ✔                  |
| [PortIn](https://os.mbed.com/docs/mbed-os/v6.13/apis/portin.html)             | ✔            | ✔                  |
| [PortOut](https://os.mbed.com/docs/mbed-os/v6.13/apis/portout.html)           | ✔            | ✔                  |
| [PortInOut](https://os.mbed.com/docs/mbed-os/v6.13/apis/portinout.html)       | ✔            | ✔                  |
| [PwmOut](https://os.mbed.com/docs/mbed-os/v6.13/apis/pwmout.html)             | ✔            | ✔                  |

## Library

header: [github](https://github.com/ARMmbed/mbed-os/tree/master/drivers/include/drivers)

source:[github](https://github.com/ARMmbed/mbed-os/tree/master/drivers/source)

[Internal Library](https://os.mbed.com/handbook/mbed-library-internals.)

##

## DigitalIn

```cpp
class DigitalIn
{
    public:
        DigitalIn(PinName pin) : gpio()
        {
            gpio_init_in(&gpio, pin);
        }

        DigitalIn(PinName pin, PinMode mode) : gpio()
        {
            gpio_init_in_ex(&gpio, pin, mode);
        }

        ~DigitalIn()
        {
            gpio_free(&gpio);
        }

        int read()
        {
            return gpio_read(&gpio);
        }

        void mode(PinMode pull);
        int is_connected()
        {
            return gpio_is_connected(&gpio);
        }

        operator int()
        {
            return read();
        }

    protected:
    #if !defined(DOXYGEN_ONLY)
        gpio_t gpio;
    #endif //!defined(DOXYGEN_ONLY)
};
```

```cpp
void DigitalIn::mode(PinMode pull)
{
    core_util_critical_section_enter();
    gpio_mode(&gpio, pull);
    core_util_critical_section_exit();
}
```

### DigitalOut

```cpp
class DigitalOut
{
public:
    DigitalOut(PinName pin) : gpio()
    {
        gpio_init_out(&gpio, pin);
    }

    DigitalOut(PinName pin, int value) : gpio()
    {
        gpio_init_out_ex(&gpio, pin, value);
    }

    void write(int value)
    {
        gpio_write(&gpio, value);
    }

    int read()
    {
        return gpio_read(&gpio);
    }

    int is_connected()
    {
        return gpio_is_connected(&gpio);
    }

    DigitalOut& operator= (int value)
    {
        write(value);
        return *this;
    }

    DigitalOut& operator= (DigitalOut& rhs);

    operator int()
    {
        return read();
    }

};
```


---

# 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 dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter:

```
GET https://ykkim.gitbook.io/ec/stm32-m4-programming/mbed-os.md?ask=<question>
```

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.