# IS31FL3236 Driver | QMK Firmware
Documentation for QMK Firmware

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# IS31FL3236 Driver ​

I²C LED driver by Lumissil. Supports a maximum of four drivers, each controlling up to 36 single-color LEDs, or 12 RGB LEDs.

IS31FL3236 Datasheet

## Usage ​

The IS31FL3236 driver code is automatically included if you are using the LED Matrix or RGB Matrix feature with the `is31fl3236` driver set, and you would use those APIs instead.

However, if you need to use the driver standalone, add this to your `rules.mk`:

make

    COMMON_VPATH += $(DRIVER_PATH)/led/issi
    SRC += is31fl3236-mono.c # For single-color
    SRC += is31fl3236.c # For RGB
    I2C_DRIVER_REQUIRED = yes

## Basic Configuration ​

Add the following to your `config.h`:

Define | Default | Description
--- | --- | ---
`IS31FL3236_SDB_PIN` | Not defined | The GPIO pin connected to the drivers' shutdown pins
`IS31FL3236_I2C_TIMEOUT` | `100` | The I²C timeout in milliseconds
`IS31FL3236_I2C_PERSISTENCE` | `0` | The number of times to retry I²C transmissions
`IS31FL3236_I2C_ADDRESS_1` | Not defined | The I²C address of driver 0
`IS31FL3236_I2C_ADDRESS_2` | Not defined | The I²C address of driver 1
`IS31FL3236_I2C_ADDRESS_3` | Not defined | The I²C address of driver 2
`IS31FL3236_I2C_ADDRESS_4` | Not defined | The I²C address of driver 3

### I²C Addressing ​

The IS31FL3236 has four possible 7-bit I²C addresses, depending on how the `AD` pin is connected.

To configure this, set the `IS31FL3236_I2C_ADDRESS_n` defines to one of the following in your `config.h`, where n denotes the driver index:

Define | Value
--- | ---
`IS31FL3236_I2C_ADDRESS_GND` | `0x3C`
`IS31FL3236_I2C_ADDRESS_SCL` | `0x3D`
`IS31FL3236_I2C_ADDRESS_SDA` | `0x3E`
`IS31FL3236_I2C_ADDRESS_VCC` | `0x3F`

## ARM/ChibiOS Configuration ​

Depending on the ChibiOS board configuration, you may need to enable and configure I²C at the keyboard level.

## LED Mapping ​

In order to use this driver, each output must be mapped to an LED index, by adding the following to your `<keyboardname>.c`:

c

    const is31fl3236_led_t PROGMEM g_is31fl3236_leds[IS31FL3236_LED_COUNT] = {
    /* Driver
         |  R     G     B */
        {0, OUT1, OUT2, OUT3},
        // etc...
    };

In this example, the red, green and blue channels for the first LED index on driver 0 all have their anodes connected to `VCC`, and their cathodes on the `OUT1`, `OUT2` and `OUT3` pins respectively.

For the single-color driver, the principle is the same, but there is only one channel:

c

    const is31fl3236_led_t PROGMEM g_is31fl3236_leds[IS31FL3236_LED_COUNT] = {
    /* Driver
         |  V */
        {0, OUT1},
        // etc...
    };

## API ​

### `struct is31fl3236_led_t` ​

Contains the PWM register addresses for a single RGB LED.

#### Members ​

- `uint8_t driver`
  The driver index of the LED, from 0 to 3.
- `uint8_t r`
  The output PWM register address for the LED's red channel (RGB driver only).
- `uint8_t g`
  The output PWM register address for the LED's green channel (RGB driver only).
- `uint8_t b`
  The output PWM register address for the LED's blue channel (RGB driver only).
- `uint8_t v`
  The output PWM register address for the LED (single-color driver only).

### `void is31fl3236_init(uint8_t index)` ​

Initialize the LED driver. This function should be called first.

#### Arguments ​

- `uint8_t index`
  The driver index.

### `void is31fl3236_write_register(uint8_t index, uint8_t reg, uint8_t data)` ​

Set the value of the given register.

#### Arguments ​

- `uint8_t index`
  The driver index.
- `uint8_t reg`
  The register address.
- `uint8_t data`
  The value to set.

### `void is31fl3236_set_color(int index, uint8_t red, uint8_t green, uint8_t blue)` ​

Set the color of a single LED (RGB driver only). This function does not immediately update the LEDs; call `is31fl3236_update_pwm_buffers()` after you are finished.

#### Arguments ​

- `int index`
  The LED index (ie. the index into the `g_is31fl3236_leds` array).
- `uint8_t red`
  The red value to set.
- `uint8_t green`
  The green value to set.
- `uint8_t blue`
  The blue value to set.

### `void is31fl3236_set_color_all(uint8_t red, uint8_t green, uint8_t blue)` ​

Set the color of all LEDs (RGB driver only).

#### Arguments ​

- `uint8_t red`
  The red value to set.
- `uint8_t green`
  The green value to set.
- `uint8_t blue`
  The blue value to set.

### `void is31fl3236_set_value(int index, uint8_t value)` ​

Set the brightness of a single LED (single-color driver only). This function does not immediately update the LEDs; call `is31fl3236_update_pwm_buffers()` after you are finished.

#### Arguments ​

- `int index`
  The LED index (ie. the index into the `g_is31fl3236_leds` array).
- `uint8_t value`
  The brightness value to set.

### `void is31fl3236_set_value_all(uint8_t value)` ​

Set the brightness of all LEDs (single-color driver only).

#### Arguments ​

- `uint8_t value`
  The brightness value to set.

### `void is31fl3236_set_led_control_register(uint8_t index, bool red, bool green, bool blue)` ​

Configure the LED control registers for a single LED (RGB driver only). This function does not immediately update the LEDs; call `is31fl3236_update_led_control_registers()` after you are finished.

#### Arguments ​

- `uint8_t index`
  The LED index (ie. the index into the `g_is31fl3236_leds` array).
- `bool red`
  Enable or disable the red channel.
- `bool green`
  Enable or disable the green channel.
- `bool blue`
  Enable or disable the blue channel.

### `void is31fl3236_set_led_control_register(uint8_t index, bool value)` ​

Configure the LED control registers for a single LED (single-color driver only). This function does not immediately update the LEDs; call `is31fl3236_update_led_control_registers()` after you are finished.

#### Arguments ​

- `uint8_t index`
  The LED index (ie. the index into the `g_is31fl3236_leds` array).
- `bool value`
  Enable or disable the LED.

### `void is31fl3236_update_pwm_buffers(uint8_t index)` ​

Flush the PWM values to the LED driver.

#### Arguments ​

- `uint8_t index`
  The driver index.

### `void is31fl3236_update_led_control_registers(uint8_t index)` ​

Flush the LED control register values to the LED driver.

#### Arguments ​

- `uint8_t index`
  The driver index.