> For the complete documentation index, see [llms.txt](https://mwx.twelite.info/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://mwx.twelite.info/latest_en/api-reference/funcs/dio.md).

# DIO General purpose IO

The following functions are used for general-purpose digital IO (DIO) operations.

* `pinMode()`
* `digitalWrite()`
* `digitalRead()`
* `attachIntDio()`
* `detachIntDio()`

## Constants

### Pin name and number

| Definition                              | Name             |
| --------------------------------------- | ---------------- |
| `const uint8_t PIN_DIGITAL::DIO0 .. 19` | DIO pins 0 to 19 |
| `const uint8_t PIN_DIGITAL::DO0 .. 1`   | DO pin 0,1       |

### Mode of pin（DIO0..19)

The following enumeration values are handled with the type name `E_PIN_MODE`.

| Definition                      | Pull-up | Name                       |
| ------------------------------- | :-----: | -------------------------- |
| `PIN_MODE::INPUT`               |   None  | Input                      |
| `PIN_MODE::OUTPUT`              |   None  | Output                     |
| `PIN_MODE::INPUT_PULLUP`        |   Yes   | Input                      |
| `PIN_MODE::OUTPUT_INIT_HIGH`    |   None  | Output(init HIGH)          |
| `PIN_MODE::OUTPUT_INIT_LOW`     |   None  | Output(init LOW)           |
| `PIN_MODE::WAKE_FALLING`        |   None  | Input, raised pin, falling |
| `PIN_MODE::WAKE_RISING`         |   None  | Input, rising pin, rising  |
| `PIN_MODE::WAKE_FALLING_PULLUP` |   Yes   | Input, raised pin, falling |
| `PIN_MODE::WAKE_RISING_PULLUP`  |   Yes   | Input, rising pin, rising  |
| `PIN_MODE::DISABLE_OUTPUT`      |   Yes   | return to the input state  |

### Mode of the pin (DO0,1)

The following enumeration values are handled with the type name `E_PIN_MODE`.

| Definition                   | Name                        |
| ---------------------------- | --------------------------- |
| `PIN_MODE::OUTPUT`           | Contribute                  |
| `PIN_MODE::OUTPUT_INIT_HIGH` | Output (initial state HIGH) |
| `PIN_MODE::OUTPUT_INIT_LOW`  | Output (initial state LOW)  |
| `PIN_MODE::DISABLE_OUTPUT`   | Stop setting output         |

### pin\_state

The following enumeration values are handled with the type name `E_PIN_STATE`.

| Definition        | Value | Name             |
| ----------------- | :---: | ---------------- |
| `PIN_STATE::HIGH` |   1   | HIGH(=Vcc) level |
| `PIN_STATE::LOW`  |   0   | LOW(=GND) level  |

### Rising and falling edge of pin

The following enumeration values are handled with the type name `E_PIN_INT_MODE`.

| Definition              | Name         |
| ----------------------- | ------------ |
| `PIN_INT_MODE::FALLING` | falling edge |
| `PIN_INT_MODE::RISING`  | rising edge  |