LCD

Introduction

ESP chips can generate various kinds of timings needed by common LCDs on the market, like SPI LCD, I2C LCD, Parallel LCD (Intel 8080), RGB/SRGB LCD, MIPI DSI LCD and etc. The esp_lcd component offers an abstracted driver framework to support them in a unified way.

An LCD typically consists of two main planes:

  • Control Plane: This plane allows us to read and write to the internal registers of the LCD device controller. Host typically uses this plane for tasks such as initializing the LCD power supply and performing gamma calibration.

  • Data Plane: The data plane is responsible for transmitting pixel data to the LCD device.

Functional Overview

In the context of esp_lcd, both the data plane and the control plane are represented by the esp_lcd_panel_handle_t type.

On some LCDs, these two planes may be combined into a single plane. In this configuration, pixel data is transmitted through the control plane, achieving functionality similar to that of the data plane. This merging is common in SPI LCDs and I2C LCDs. Additionally, there are LCDs that do not require a separate control plane. For instance, certain RGB LCDs automatically execute necessary initialization procedures after power-up. Host devices only need to continuously refresh pixel data through the data plane. However, it's essential to note that not all RGB LCDs eliminate the control plane entirely. Some LCD devices can simultaneously support multiple interfaces, requiring the host to send specific commands via the control plane (such as those based on the SPI interface) to enable the RGB mode.

This document will discuss how to create the control plane and data plane, as mentioned earlier, based on different types of LCDs.

备注

ESP-IDF provides only a limited number of LCD device controller drivers out of the box (e.g., ST7789), more drivers are available in the Espressif Component Registry.

LCD Control Panel Operations

LCD Data Panel Operations

  • esp_lcd_panel_reset() can reset the LCD data panel.

  • esp_lcd_panel_init() performs a basic initialization of the data panel.

  • esp_lcd_panel_draw_bitmap() is the function which does the magic to flush the user draw buffer to the LCD screen, where the target draw window is configurable. Please note, this function expects the draw buffer is a 1-D array and there's no stride in between each lines.

Steps to Add Manufacture Specific Initialization

The LCD controller drivers (e.g., st7789) in ESP-IDF only provide basic initialization in the esp_lcd_panel_init(), leaving the vast majority of settings to the default values. Some LCD modules needs to set a bunch of manufacture specific configurations before it can display normally. These configurations usually include gamma, power voltage and so on. If you want to add manufacture specific initialization, please follow the steps below:

esp_lcd_panel_reset(panel_handle);
esp_lcd_panel_init(panel_handle);
// set extra configurations e.g., gamma control
// with the underlying IO handle
// please consult your manufacture for special commands and corresponding values
esp_lcd_panel_io_tx_param(io_handle, GAMMA_CMD, (uint8_t[]) {
       GAMMA_ARRAY
    }, N);
// turn on the display
esp_lcd_panel_disp_on_off(panel_handle, true);

Application Example

API Reference

Header File

Type Definitions

typedef soc_periph_lcd_clk_src_t lcd_clock_source_t

LCD clock source.

Enumerations

enum lcd_rgb_data_endian_t

RGB data endian.

Values:

enumerator LCD_RGB_DATA_ENDIAN_BIG

RGB data endian: MSB first

enumerator LCD_RGB_DATA_ENDIAN_LITTLE

RGB data endian: LSB first

enum lcd_color_space_t

LCD color space.

Values:

enumerator LCD_COLOR_SPACE_RGB

Color space: RGB

enumerator LCD_COLOR_SPACE_YUV

Color space: YUV

enum lcd_color_rgb_pixel_format_t

LCD color pixel format in RGB color space.

Values:

enumerator LCD_COLOR_PIXEL_FORMAT_RGB565

16 bits, 5 bits per R/B value, 6 bits for G value

enumerator LCD_COLOR_PIXEL_FORMAT_RGB666

18 bits, 6 bits per R/G/B value

enumerator LCD_COLOR_PIXEL_FORMAT_RGB888

24 bits, 8 bits per R/G/B value

enum lcd_color_range_t

LCD color range.

Values:

enumerator LCD_COLOR_RANGE_LIMIT

Limited color range

enumerator LCD_COLOR_RANGE_FULL

Full color range

enum lcd_yuv_sample_t

YUV sampling method.

Values:

enumerator LCD_YUV_SAMPLE_422

YUV 4:2:2 sampling

enumerator LCD_YUV_SAMPLE_420

YUV 4:2:0 sampling

enumerator LCD_YUV_SAMPLE_411

YUV 4:1:1 sampling

enum lcd_yuv_conv_std_t

The standard used for conversion between RGB and YUV.

Values:

enumerator LCD_YUV_CONV_STD_BT601

YUV<->RGB conversion standard: BT.601

enumerator LCD_YUV_CONV_STD_BT709

YUV<->RGB conversion standard: BT.709

Header File

  • components/esp_lcd/include/esp_lcd_types.h

  • This header file can be included with:

    #include "esp_lcd_types.h"

  • This header file is a part of the API provided by the esp_lcd component. To declare that your component depends on esp_lcd, add the following to your CMakeLists.txt:

    REQUIRES esp_lcd

    or

    PRIV_REQUIRES esp_lcd

Structures

struct esp_lcd_video_timing_t

Timing parameters for the video data transmission.

Public Members

uint32_t h_size

Horizontal resolution, i.e. the number of pixels in a line

uint32_t v_size

Vertical resolution, i.e. the number of lines in the frame

uint32_t hsync_pulse_width

Horizontal sync width, in pixel clock

uint32_t hsync_back_porch

Horizontal back porch, number of pixel clock between hsync and start of line active data

uint32_t hsync_front_porch

Horizontal front porch, number of pixel clock between the end of active data and the next hsync

uint32_t vsync_pulse_width

Vertical sync width, in number of lines

uint32_t vsync_back_porch

Vertical back porch, number of invalid lines between vsync and start of frame

uint32_t vsync_front_porch

Vertical front porch, number of invalid lines between the end of frame and the next vsync

Type Definitions

typedef struct esp_lcd_panel_io_t *esp_lcd_panel_io_handle_t

Type of LCD panel IO handle

typedef struct esp_lcd_panel_t *esp_lcd_panel_handle_t

Type of LCD panel handle

Enumerations

enum lcd_rgb_element_order_t

RGB element order.

Values:

enumerator LCD_RGB_ELEMENT_ORDER_RGB

RGB element order: RGB

enumerator LCD_RGB_ELEMENT_ORDER_BGR

RGB element order: BGR

Header File

  • components/esp_lcd/include/esp_lcd_panel_io.h

  • This header file can be included with:

    #include "esp_lcd_panel_io.h"

  • This header file is a part of the API provided by the esp_lcd component. To declare that your component depends on esp_lcd, add the following to your CMakeLists.txt:

    REQUIRES esp_lcd

    or

    PRIV_REQUIRES esp_lcd

Functions

esp_err_t esp_lcd_panel_io_rx_param(esp_lcd_panel_io_handle_t io, int lcd_cmd, void *param, size_t param_size)

Transmit LCD command and receive corresponding parameters.

备注

Commands sent by this function are short, so they are sent using polling transactions. The function does not return before the command transfer is completed. If any queued transactions sent by esp_lcd_panel_io_tx_color() are still pending when this function is called, this function will wait until they are finished and the queue is empty before sending the command(s).

参数

  • io -- [in] LCD panel IO handle, which is created by other factory API like esp_lcd_new_panel_io_spi()

  • lcd_cmd -- [in] The specific LCD command, set to -1 if no command needed

  • param -- [out] Buffer for the command data

  • param_size -- [in] Size of param buffer

返回

  • ESP_ERR_INVALID_ARG if parameter is invalid

  • ESP_ERR_NOT_SUPPORTED if read is not supported by transport

  • ESP_OK on success

esp_err_t esp_lcd_panel_io_tx_param(esp_lcd_panel_io_handle_t io, int lcd_cmd, const void *param, size_t param_size)

Transmit LCD command and corresponding parameters.

备注

Commands sent by this function are short, so they are sent using polling transactions. The function does not return before the command transfer is completed. If any queued transactions sent by esp_lcd_panel_io_tx_color() are still pending when this function is called, this function will wait until they are finished and the queue is empty before sending the command(s).

参数

  • io -- [in] LCD panel IO handle, which is created by other factory API like esp_lcd_new_panel_io_spi()

  • lcd_cmd -- [in] The specific LCD command, set to -1 if no command needed

  • param -- [in] Buffer that holds the command specific parameters, set to NULL if no parameter is needed for the command

  • param_size -- [in] Size of param in memory, in bytes, set to zero if no parameter is needed for the command

返回

  • ESP_ERR_INVALID_ARG if parameter is invalid

  • ESP_OK on success

esp_err_t esp_lcd_panel_io_tx_color(esp_lcd_panel_io_handle_t io, int lcd_cmd, const void *color, size_t color_size)

Transmit LCD RGB data.

备注

This function will package the command and RGB data into a transaction, and push into a queue. The real transmission is performed in the background (DMA+interrupt). The caller should take care of the lifecycle of the color buffer. Recycling of color buffer should be done in the callback on_color_trans_done().

参数

  • io -- [in] LCD panel IO handle, which is created by factory API like esp_lcd_new_panel_io_spi()

  • lcd_cmd -- [in] The specific LCD command, set to -1 if no command needed

  • color -- [in] Buffer that holds the RGB color data

  • color_size -- [in] Size of color in memory, in bytes

返回

  • ESP_ERR_INVALID_ARG if parameter is invalid

  • ESP_OK on success

esp_err_t esp_lcd_panel_io_del(esp_lcd_panel_io_handle_t io)

Destroy LCD panel IO handle (deinitialize panel and free all corresponding resource)

参数

io -- [in] LCD panel IO handle, which is created by factory API like esp_lcd_new_panel_io_spi()

返回

  • ESP_ERR_INVALID_ARG if parameter is invalid

  • ESP_OK on success

esp_err_t esp_lcd_panel_io_register_event_callbacks(esp_lcd_panel_io_handle_t io, const esp_lcd_panel_io_callbacks_t *cbs, void *user_ctx)

Register LCD panel IO callbacks.

参数

  • io -- [in] LCD panel IO handle, which is created by factory API like esp_lcd_new_panel_io_spi()

  • cbs -- [in] structure with all LCD panel IO callbacks

  • user_ctx -- [in] User private data, passed directly to callback's user_ctx

返回

  • ESP_ERR_INVALID_ARG if parameter is invalid

  • ESP_OK on success

esp_err_t esp_lcd_new_panel_io_spi(esp_lcd_spi_bus_handle_t bus, const esp_lcd_panel_io_spi_config_t *io_config, esp_lcd_panel_io_handle_t *ret_io)

Create LCD panel IO handle, for SPI interface.

参数

  • bus -- [in] SPI bus handle

  • io_config -- [in] IO configuration, for SPI interface

  • ret_io -- [out] Returned IO handle

返回

  • ESP_ERR_INVALID_ARG if parameter is invalid

  • ESP_ERR_NO_MEM if out of memory

  • ESP_OK on success

esp_err_t esp_lcd_new_panel_io_i2c_v1(uint32_t bus, const esp_lcd_panel_io_i2c_config_t *io_config, esp_lcd_panel_io_handle_t *ret_io)

Create LCD panel IO handle, for I2C interface in legacy implementation.

备注

Please don't call this function in your project directly. Please call esp_lcd_new_panel_to_i2c instead.

参数

  • bus -- [in] I2C bus handle, (in uint32_t)

  • io_config -- [in] IO configuration, for I2C interface

  • ret_io -- [out] Returned IO handle

返回

  • ESP_ERR_INVALID_ARG if parameter is invalid

  • ESP_ERR_NO_MEM if out of memory

  • ESP_OK on success

esp_err_t esp_lcd_new_panel_io_i2c_v2(i2c_master_bus_handle_t bus, const esp_lcd_panel_io_i2c_config_t *io_config, esp_lcd_panel_io_handle_t *ret_io)

Create LCD panel IO handle, for I2C interface in new implementation.

备注

Please don't call this function in your project directly. Please call esp_lcd_new_panel_to_i2c instead.

参数

  • bus -- [in] I2C bus handle, (in i2c_master_dev_handle_t)

  • io_config -- [in] IO configuration, for I2C interface

  • ret_io -- [out] Returned IO handle

返回

  • ESP_ERR_INVALID_ARG if parameter is invalid

  • ESP_ERR_NO_MEM if out of memory

  • ESP_OK on success

esp_err_t esp_lcd_new_i80_bus(const esp_lcd_i80_bus_config_t *bus_config, esp_lcd_i80_bus_handle_t *ret_bus)

Create Intel 8080 bus handle.

参数

  • bus_config -- [in] Bus configuration

  • ret_bus -- [out] Returned bus handle

返回

  • ESP_ERR_INVALID_ARG if parameter is invalid

  • ESP_ERR_NO_MEM if out of memory

  • ESP_ERR_NOT_FOUND if no free bus is available

  • ESP_OK on success

esp_err_t esp_lcd_del_i80_bus(esp_lcd_i80_bus_handle_t bus)

Destroy Intel 8080 bus handle.

参数

bus -- [in] Intel 8080 bus handle, created by esp_lcd_new_i80_bus()

返回

  • ESP_ERR_INVALID_ARG if parameter is invalid

  • ESP_ERR_INVALID_STATE if there still be some device attached to the bus

  • ESP_OK on success

esp_err_t esp_lcd_new_panel_io_i80(esp_lcd_i80_bus_handle_t bus, const esp_lcd_panel_io_i80_config_t *io_config, esp_lcd_panel_io_handle_t *ret_io)

Create LCD panel IO, for Intel 8080 interface.

参数

  • bus -- [in] Intel 8080 bus handle, created by esp_lcd_new_i80_bus()

  • io_config -- [in] IO configuration, for i80 interface

  • ret_io -- [out] Returned panel IO handle

返回

  • ESP_ERR_INVALID_ARG if parameter is invalid

  • ESP_ERR_NOT_SUPPORTED if some configuration can't be satisfied, e.g. pixel clock out of the range

  • ESP_ERR_NO_MEM if out of memory

  • ESP_OK on success

Structures

struct esp_lcd_panel_io_event_data_t

Type of LCD panel IO event data.

struct esp_lcd_panel_io_callbacks_t

Type of LCD panel IO callbacks.

Public Members

esp_lcd_panel_io_color_trans_done_cb_t on_color_trans_done

Callback invoked when color data transfer has finished

struct esp_lcd_panel_io_spi_config_t

Panel IO configuration structure, for SPI interface.

Public Members

int cs_gpio_num

GPIO used for CS line

int dc_gpio_num

GPIO used to select the D/C line, set this to -1 if the D/C line is not used

int spi_mode

Traditional SPI mode (0~3)

unsigned int pclk_hz

Frequency of pixel clock

size_t trans_queue_depth

Size of internal transaction queue

esp_lcd_panel_io_color_trans_done_cb_t on_color_trans_done

Callback invoked when color data transfer has finished

void *user_ctx

User private data, passed directly to on_color_trans_done's user_ctx

int lcd_cmd_bits

Bit-width of LCD command

int lcd_param_bits

Bit-width of LCD parameter

unsigned int dc_high_on_cmd

If enabled, DC level = 1 indicates command transfer

unsigned int dc_low_on_data

If enabled, DC level = 0 indicates color data transfer

unsigned int dc_low_on_param

If enabled, DC level = 0 indicates parameter transfer

unsigned int octal_mode

transmit with octal mode (8 data lines), this mode is used to simulate Intel 8080 timing

unsigned int quad_mode

transmit with quad mode (4 data lines), this mode is useful when transmitting LCD parameters (Only use one line for command)

unsigned int sio_mode

Read and write through a single data line (MOSI)

unsigned int lsb_first

transmit LSB bit first

unsigned int cs_high_active

CS line is high active

struct esp_lcd_panel_io_spi_config_t::[anonymous] flags

Extra flags to fine-tune the SPI device

struct esp_lcd_panel_io_i2c_config_t

Panel IO configuration structure, for I2C interface.

Public Members

uint32_t dev_addr

I2C device address

esp_lcd_panel_io_color_trans_done_cb_t on_color_trans_done

Callback invoked when color data transfer has finished

void *user_ctx

User private data, passed directly to on_color_trans_done's user_ctx

size_t control_phase_bytes

I2C LCD panel will encode control information (e.g. D/C selection) into control phase, in several bytes

unsigned int dc_bit_offset

Offset of the D/C selection bit in control phase

int lcd_cmd_bits

Bit-width of LCD command

int lcd_param_bits

Bit-width of LCD parameter

unsigned int dc_low_on_data

If this flag is enabled, DC line = 0 means transfer data, DC line = 1 means transfer command; vice versa

unsigned int disable_control_phase

If this flag is enabled, the control phase isn't used

struct esp_lcd_panel_io_i2c_config_t::[anonymous] flags

Extra flags to fine-tune the I2C device

uint32_t scl_speed_hz

I2C LCD SCL frequency (hz)

struct esp_lcd_i80_bus_config_t

LCD Intel 8080 bus configuration structure.

Public Members

int dc_gpio_num

GPIO used for D/C line

int wr_gpio_num

GPIO used for WR line

lcd_clock_source_t clk_src

Clock source for the I80 LCD peripheral

int data_gpio_nums[ESP_LCD_I80_BUS_WIDTH_MAX]

GPIOs used for data lines

size_t bus_width

Number of data lines, 8 or 16

size_t max_transfer_bytes

Maximum transfer size, this determines the length of internal DMA link

size_t psram_trans_align

DMA transfer alignment for data allocated from PSRAM

size_t sram_trans_align

DMA transfer alignment for data allocated from SRAM

struct esp_lcd_panel_io_i80_config_t

Panel IO configuration structure, for intel 8080 interface.

Public Members

int cs_gpio_num

GPIO used for CS line, set to -1 will declaim exclusively use of I80 bus

uint32_t pclk_hz

Frequency of pixel clock

size_t trans_queue_depth

Transaction queue size, larger queue, higher throughput

esp_lcd_panel_io_color_trans_done_cb_t on_color_trans_done

Callback invoked when color data was transferred done

void *user_ctx

User private data, passed directly to on_color_trans_done's user_ctx

int lcd_cmd_bits

Bit-width of LCD command

int lcd_param_bits

Bit-width of LCD parameter

unsigned int dc_idle_level

Level of DC line in IDLE phase

unsigned int dc_cmd_level

Level of DC line in CMD phase

unsigned int dc_dummy_level

Level of DC line in DUMMY phase

unsigned int dc_data_level

Level of DC line in DATA phase

struct esp_lcd_panel_io_i80_config_t::[anonymous] dc_levels

Each i80 device might have its own D/C control logic

unsigned int cs_active_high

If set, a high level of CS line will select the device, otherwise, CS line is low level active

unsigned int reverse_color_bits

Reverse the data bits, D[N:0] -> D[0:N]

unsigned int swap_color_bytes

Swap adjacent two color bytes

unsigned int pclk_active_neg

The display will write data lines when there's a falling edge on WR signal (a.k.a the PCLK)

unsigned int pclk_idle_low

The WR signal (a.k.a the PCLK) stays at low level in IDLE phase

struct esp_lcd_panel_io_i80_config_t::[anonymous] flags

Panel IO config flags

Macros

ESP_LCD_I80_BUS_WIDTH_MAX

Maximum width of I80 bus

esp_lcd_new_panel_io_i2c(bus, io_config, ret_io)

Create LCD panel IO handle.

参数

  • bus -- [in] I2C bus handle

  • io_config -- [in] IO configuration, for I2C interface

  • ret_io -- [out] Returned IO handle

返回

  • ESP_ERR_INVALID_ARG if parameter is invalid

  • ESP_ERR_NO_MEM if out of memory

  • ESP_OK on success

Type Definitions

typedef void *esp_lcd_spi_bus_handle_t

Type of LCD SPI bus handle

typedef uint32_t esp_lcd_i2c_bus_handle_t

Type of LCD I2C bus handle

typedef struct esp_lcd_i80_bus_t *esp_lcd_i80_bus_handle_t

Type of LCD intel 8080 bus handle

typedef bool (*esp_lcd_panel_io_color_trans_done_cb_t)(esp_lcd_panel_io_handle_t panel_io, esp_lcd_panel_io_event_data_t *edata, void *user_ctx)

Declare the prototype of the function that will be invoked when panel IO finishes transferring color data.

Param panel_io

[in] LCD panel IO handle, which is created by factory API like esp_lcd_new_panel_io_spi()

Param edata

[in] Panel IO event data, fed by driver

Param user_ctx

[in] User data, passed from esp_lcd_panel_io_xxx_config_t

Return

Whether a high priority task has been waken up by this function

Header File

  • components/esp_lcd/include/esp_lcd_panel_ops.h

  • This header file can be included with:

    #include "esp_lcd_panel_ops.h"

  • This header file is a part of the API provided by the esp_lcd component. To declare that your component depends on esp_lcd, add the following to your CMakeLists.txt:

    REQUIRES esp_lcd

    or

    PRIV_REQUIRES esp_lcd

Functions

esp_err_t esp_lcd_panel_reset(esp_lcd_panel_handle_t panel)

Reset LCD panel.

备注

Panel reset must be called before attempting to initialize the panel using esp_lcd_panel_init().

参数

panel -- [in] LCD panel handle, which is created by other factory API like esp_lcd_new_panel_st7789()

返回

  • ESP_OK on success

esp_err_t esp_lcd_panel_init(esp_lcd_panel_handle_t panel)

Initialize LCD panel.

备注

Before calling this function, make sure the LCD panel has finished the reset stage by esp_lcd_panel_reset().

参数

panel -- [in] LCD panel handle, which is created by other factory API like esp_lcd_new_panel_st7789()

返回

  • ESP_OK on success

esp_err_t esp_lcd_panel_del(esp_lcd_panel_handle_t panel)

Deinitialize the LCD panel.

参数

panel -- [in] LCD panel handle, which is created by other factory API like esp_lcd_new_panel_st7789()

返回

  • ESP_OK on success

esp_err_t esp_lcd_panel_draw_bitmap(esp_lcd_panel_handle_t panel, int x_start, int y_start, int x_end, int y_end, const void *color_data)

Draw bitmap on LCD panel.

参数

  • panel -- [in] LCD panel handle, which is created by other factory API like esp_lcd_new_panel_st7789()

  • x_start -- [in] Start pixel index in the target frame buffer, on x-axis (x_start is included)

  • y_start -- [in] Start pixel index in the target frame buffer, on y-axis (y_start is included)

  • x_end -- [in] End pixel index in the target frame buffer, on x-axis (x_end is not included)

  • y_end -- [in] End pixel index in the target frame buffer, on y-axis (y_end is not included)

  • color_data -- [in] RGB color data that will be dumped to the specific window range

返回

  • ESP_OK on success

esp_err_t esp_lcd_panel_mirror(esp_lcd_panel_handle_t panel, bool mirror_x, bool mirror_y)

Mirror the LCD panel on specific axis.

备注

Combined with esp_lcd_panel_swap_xy(), one can realize screen rotation

参数

  • panel -- [in] LCD panel handle, which is created by other factory API like esp_lcd_new_panel_st7789()

  • mirror_x -- [in] Whether the panel will be mirrored about the x axis

  • mirror_y -- [in] Whether the panel will be mirrored about the y axis

返回

  • ESP_OK on success

  • ESP_ERR_NOT_SUPPORTED if this function is not supported by the panel

esp_err_t esp_lcd_panel_swap_xy(esp_lcd_panel_handle_t panel, bool swap_axes)

Swap/Exchange x and y axis.

备注

Combined with esp_lcd_panel_mirror(), one can realize screen rotation

参数

  • panel -- [in] LCD panel handle, which is created by other factory API like esp_lcd_new_panel_st7789()

  • swap_axes -- [in] Whether to swap the x and y axis

返回

  • ESP_OK on success

  • ESP_ERR_NOT_SUPPORTED if this function is not supported by the panel

esp_err_t esp_lcd_panel_set_gap(esp_lcd_panel_handle_t panel, int x_gap, int y_gap)

Set extra gap in x and y axis.

The gap is the space (in pixels) between the left/top sides of the LCD panel and the first row/column respectively of the actual contents displayed.

备注

Setting a gap is useful when positioning or centering a frame that is smaller than the LCD.

参数

  • panel -- [in] LCD panel handle, which is created by other factory API like esp_lcd_new_panel_st7789()

  • x_gap -- [in] Extra gap on x axis, in pixels

  • y_gap -- [in] Extra gap on y axis, in pixels

返回

  • ESP_OK on success

esp_err_t esp_lcd_panel_invert_color(esp_lcd_panel_handle_t panel, bool invert_color_data)

Invert the color (bit-wise invert the color data line)

参数

  • panel -- [in] LCD panel handle, which is created by other factory API like esp_lcd_new_panel_st7789()

  • invert_color_data -- [in] Whether to invert the color data

返回

  • ESP_OK on success

esp_err_t esp_lcd_panel_disp_on_off(esp_lcd_panel_handle_t panel, bool on_off)

Turn on or off the display.

参数

  • panel -- [in] LCD panel handle, which is created by other factory API like esp_lcd_new_panel_st7789()

  • on_off -- [in] True to turns on display, False to turns off display

返回

  • ESP_OK on success

  • ESP_ERR_NOT_SUPPORTED if this function is not supported by the panel

esp_err_t esp_lcd_panel_disp_off(esp_lcd_panel_handle_t panel, bool off)

Turn off the display.

参数

  • panel -- [in] LCD panel handle, which is created by other factory API like esp_lcd_new_panel_st7789()

  • off -- [in] Whether to turn off the screen

返回

  • ESP_OK on success

  • ESP_ERR_NOT_SUPPORTED if this function is not supported by the panel

esp_err_t esp_lcd_panel_disp_sleep(esp_lcd_panel_handle_t panel, bool sleep)

Enter or exit sleep mode.

参数

  • panel -- [in] LCD panel handle, which is created by other factory API like esp_lcd_new_panel_st7789()

  • sleep -- [in] True to enter sleep mode, False to wake up

返回

  • ESP_OK on success

  • ESP_ERR_NOT_SUPPORTED if this function is not supported by the panel

Header File

  • components/esp_lcd/include/esp_lcd_panel_vendor.h

  • This header file can be included with:

    #include "esp_lcd_panel_vendor.h"

  • This header file is a part of the API provided by the esp_lcd component. To declare that your component depends on esp_lcd, add the following to your CMakeLists.txt:

    REQUIRES esp_lcd

    or

    PRIV_REQUIRES esp_lcd

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