.. _ili9341:


=============================
ILI9341 LCD Controller Driver
=============================

Overview
********

The `ILI9341 <https://www.buydisplay.com/download/ic/ILI9341.pdf>`__ is a
262,144-color single-chip SOC driver for a-TFT liquid crystal display with resolution
of 240RGBx320 dots, comprising a 720-channel source driver, a 320-channel gate
driver, 172,800 bytes GRAM for graphic display data of 240RGBx320 dots, and power
supply circuit. ILI9341 supports parallel 8-/9-/16-/18-bit data bus MCU interface,
6-/16-/18-bit data bus RGB interface and 3-/4-line serial peripheral interface(SPI).

The ILI9341 LCD controller
`driver <https://github.com/lvgl/lvgl/tree/master/src/drivers/display/ili9341>`__ is
a platform-agnostic driver, based on the :ref:`generic MIPI driver`.  It implements
display initialization, supports display rotation and implements the display flush
callback.  The user needs to implement only two platform-specific functions to send a
command or pixel data to the controller via SPI or parallel bus.  Typically these are
implemented by calling the appropriate SDK library functions on the given platform.



Prerequisites
*************

There are no prerequisites.



Configuring the Driver
**********************

Enable the ILI9341 driver support in lv_conf.h, by cmake compiler define or by KConfig:

.. code-block:: c

    #define LV_USE_ILI9341  1



Usage
*****

You need to implement two platform-dependent functions:

.. code-block:: c

    /* Send short command to the LCD. This function shall wait until the transaction finishes. */
    void my_lcd_send_cmd(lv_display_t *disp, const uint8_t *cmd, size_t cmd_size, const uint8_t *param, size_t param_size)
    {
        ...
    }

    /* Send large array of pixel data to the LCD. If necessary, this function has to
     * do the byte-swapping. This function can do the transfer in the background. */
    void my_lcd_send_color(lv_display_t *disp, const uint8_t *cmd, size_t cmd_size, uint8_t *param, size_t param_size)
    {
        ...
    }

To create an ILI9341-based display use the function

.. code-block:: c

    /**
     * Create an LCD display with ILI9341 driver
     * @param hor_res       horizontal resolution
     * @param ver_res       vertical resolution
     * @param flags         default configuration settings (mirror, RGB ordering, etc.)
     * @param send_cmd      platform-dependent function to send a command to the LCD controller (usually uses polling transfer)
     * @param send_color    platform-dependent function to send pixel data to the LCD controller (usually uses DMA transfer: must implement a 'ready' callback)
     * @return              pointer to the created display
     */
    lv_display_t * lv_ili9341_create(uint32_t hor_res, uint32_t ver_res, lv_lcd_flag_t flags,
                                    lv_ili9341_send_cmd_cb_t send_cmd_cb, lv_ili9341_send_color_cb_t send_color_cb);

For additional details and a working example see the :ref:`generic MIPI driver`
documentation.
