之前用3线SPI驱动的HX8347屏其实是一个RGB屏，SPI只是用来给RGB屏幕的做配置的，当然也可以用来驱动屏幕，但是3线SPI驱动能力终究有限。本文谈一下用RGB方式来驱动。
RGB接线比较多，为此做了个转接板：
一、源码
1、screen_rgb_spi.c用于SPI初始化屏幕
screen_rgb_spi.h
#ifndef SCREEN_RGB_SPI_H_
#define SCREEN_RGB_SPI_H_
void rgb_spi_init(void) ;
#endif
screen_rgb_spi.c
#include <stdio.h>
#include <string.h>
#include "freertos/FreeRTOS.h"
#include "freertos/task.h"
#include "soc/soc_caps.h"
#include "driver/gpio.h"
#include "driver/spi_master.h"
#include "esp_log.h"
#include "screen_rgb_spi.h"
static const char *TAG = "SCREN_REG_SPI";
#define LCD_HOST SPI2_HOST
#define PIN_NUM_MISO 4 //37
#define PIN_NUM_MOSI 5 //36
#define PIN_NUM_CLK 3 //38
#define PIN_NUM_CS 6 //35
#define PIN_NUM_DC -1
#define PIN_NUM_RST 2 //39
#define PIN_NUM_BCKL 1
static spi_device_handle_t g_screen_spi;
static int lcd_cs_port(int status)
{
if (status) {
gpio_set_level(PIN_NUM_CS, 1);
} else {
gpio_set_level(PIN_NUM_CS, 0);
}
return 0;
}
static void spi_writeData(spi_device_handle_t spi,uint8_t data)
{
esp_err_t ret;
spi_transaction_t t;
memset(&t, 0, sizeof(t));
t.length = 8;
t.tx_buffer = &data;
ret = spi_device_polling_transmit(spi, &t); //Transmit!
assert(ret==ESP_OK);
}
static void lcd_cmd(spi_device_handle_t spi, const uint8_t data) {
lcd_cs_port(0);
spi_writeData(spi,0x70);
spi_writeData(spi,data);
lcd_cs_port(1);
}
static void lcd_data(spi_device_handle_t spi, const uint8_t data) {
lcd_cs_port(0);
spi_writeData(spi,0x72);
spi_writeData(spi,data);
lcd_cs_port(1);
}
static void LCD_WriteComm(uint8_t cmd) {
lcd_cmd(g_screen_spi, cmd);
}
static void LCD_WriteData(uint8_t data) {
lcd_data(g_screen_spi, data);
}
void LCD_WriteData_16Bit(uint16_t Data)
{
lcd_cs_port(0);
spi_writeData(g_screen_spi,0x72);
spi_writeData(g_screen_spi,Data>>8);
spi_writeData(g_screen_spi,Data);
lcd_cs_port(1);
}
void Lcd_Write_REG(uint8_t Index,uint8_t Data)
{
LCD_WriteComm(Index);
LCD_WriteData(Data);
}
void LCD_Init(void)
{
gpio_set_level(PIN_NUM_BCKL,1);
gpio_set_level(PIN_NUM_RST, 0);
vTaskDelay(100/portTICK_PERIOD_MS);
gpio_set_level(PIN_NUM_RST, 1);
vTaskDelay(100/portTICK_PERIOD_MS);
Lcd_Write_REG(0x18,0xff); //UADJ 75Hz
Lcd_Write_REG(0x19,0x01); //OSC_EN='1', start Osc
//Power Voltage Setting
Lcd_Write_REG(0x1B,0x1E); // 1e VRH=4.60V
Lcd_Write_REG(0x1C,0x07); //AP Crosstalk 04
Lcd_Write_REG(0x1A,0x01); //BT (VGH~15V,VGL~-10V,DDVDH~5V)
Lcd_Write_REG(0x24,0x38); //VMH 27
Lcd_Write_REG(0x25,0x5F); //VML
//VCOM offset
Lcd_Write_REG(0x23,0x8C); //for Flicker adjust
Lcd_Write_REG(0x1F,0x88);// GAS=1, VOMG=00, PON=0, DK=1, XDK=0, DVDH_TRI=0, STB=0
vTaskDelay(5/portTICK_PERIOD_MS);
Lcd_Write_REG(0x1F,0x80);// GAS=1, VOMG=00, PON=0, DK=0, XDK=0, DVDH_TRI=0, STB=0
vTaskDelay(5/portTICK_PERIOD_MS);
Lcd_Write_REG(0x1F,0x90);// GAS=1, VOMG=00, PON=1, DK=0, XDK=0, DVDH_TRI=0, STB=0
vTaskDelay(5/portTICK_PERIOD_MS);
Lcd_Write_REG(0x1F,0xD0);// GAS=1, VOMG=10, PON=1, DK=0, XDK=0, DDVDH_TRI=0, STB=0
vTaskDelay(5/portTICK_PERIOD_MS);
//Display ON Setting
Lcd_Write_REG(0x28,0x38); //GON=1, DTE=1, D=1000
vTaskDelay(40/portTICK_PERIOD_MS);
Lcd_Write_REG(0x28,0x3C); //GON=1, DTE=1, D=1100
Lcd_Write_REG(0x36,0x09); //09 REV, BGR 翻转 RGB控制
Lcd_Write_REG(0x17,0x50); //16BIT/PIXEL
// //Gamma 2.2 Setting
Lcd_Write_REG(0x40,0x01); //
Lcd_Write_REG(0x41,0x00); //
Lcd_Write_REG(0x42,0x00); //
Lcd_Write_REG(0x43,0x10); //
Lcd_Write_REG(0x44,0x0E); //
Lcd_Write_REG(0x45,0x24); //
Lcd_Write_REG(0x46,0x04); //
Lcd_Write_REG(0x47,0x50); //
Lcd_Write_REG(0x48,0x02); //
Lcd_Write_REG(0x49,0x13); //
Lcd_Write_REG(0x4A,0x19); //
Lcd_Write_REG(0x4B,0x19); //
Lcd_Write_REG(0x4C,0x16); //
Lcd_Write_REG(0x50,0x1B); //
Lcd_Write_REG(0x51,0x31); //
Lcd_Write_REG(0x52,0x2F); //
Lcd_Write_REG(0x53,0x3F); //
Lcd_Write_REG(0x54,0x3F); //
Lcd_Write_REG(0x55,0x3E); //
Lcd_Write_REG(0x56,0x2F); //
Lcd_Write_REG(0x57,0x7B); //
Lcd_Write_REG(0x58,0x09); //
Lcd_Write_REG(0x59,0x06); //
Lcd_Write_REG(0x5A,0x06); //
Lcd_Write_REG(0x5B,0x0C); //
Lcd_Write_REG(0x5C,0x1D); //
Lcd_Write_REG(0x5D,0xCC); //
//Set Window Area
Lcd_Write_REG(0x02,0x00);
Lcd_Write_REG(0x03,0x00); //Column Start
Lcd_Write_REG(0x04,0x00);
Lcd_Write_REG(0x05,0xEF); //Column End
Lcd_Write_REG(0x06,0x00);
Lcd_Write_REG(0x07,0x00); //Row Start
Lcd_Write_REG(0x08,0x01);
Lcd_Write_REG(0x09,0x3F); //Row End
Lcd_Write_REG(0x31,0x02); //RGB Interface(1) (VS+HS+DE)
Lcd_Write_REG(0x32,0x00); //DPL:(08) HSPL(04)VSPL(02) EPL (01)
Lcd_Write_REG(0x33,0x02);
Lcd_Write_REG(0x34,0x02);
}
void rgb_spi_init(void)
{
esp_err_t ret;
gpio_config_t io_conf = {};
spi_bus_config_t buscfg={
.miso_io_num=PIN_NUM_MISO,
.mosi_io_num=PIN_NUM_MOSI,
.sclk_io_num=PIN_NUM_CLK,
.quadwp_io_num=-1,
.quadhd_io_num=-1,
.max_transfer_sz=16*320
};
spi_device_interface_config_t devcfg={
.clock_speed_hz=40*1000*1000, //Clock out at 10 MHz
.mode=0, //SPI mode 0
//.spics_io_num=PIN_NUM_CS, //CS pin
.queue_size=1, //We want to be able to queue 7 transactions at a time
};
//Initialize the lcd gpio
io_conf.pin_bit_mask = ( (1ULL<<PIN_NUM_RST) |(1ULL<<PIN_NUM_CS)|(1ULL<<PIN_NUM_BCKL));
io_conf.mode = GPIO_MODE_OUTPUT;
io_conf.pull_up_en = true;
gpio_config(&io_conf);
//Initialize the SPI bus
ret=spi_bus_initialize(LCD_HOST, &buscfg, SPI_DMA_CH_AUTO);
ESP_ERROR_CHECK(ret);
// //Attach the LCD to the SPI bus
ret=spi_bus_add_device(LCD_HOST, &devcfg, &g_screen_spi);
ESP_ERROR_CHECK(ret);
//Initialize the LCD
LCD_Init();
spi_bus_remove_device(g_screen_spi);
spi_bus_free(LCD_HOST);
}
2、rgb_lcd_example_main.c主程序
/*
* SPDX-FileCopyrightText: 2022 Espressif Systems (Shanghai) CO LTD
*
* SPDX-License-Identifier: CC0-1.0
*/
#include <stdio.h>
#include "sdkconfig.h"
#include "freertos/FreeRTOS.h"
#include "freertos/task.h"
#include "freertos/semphr.h"
#include "esp_timer.h"
#include "esp_lcd_panel_ops.h"
#include "esp_lcd_panel_rgb.h"
#include "driver/gpio.h"
#include "esp_err.h"
#include "esp_log.h"
#include "lvgl.h"
#include "screen_rgb_spi.h"
#include "demos/lv_demos.h"
static const char *TAG = "example";
Please update the following configuration according to your LCD spec //
#define EXAMPLE_LCD_PIXEL_CLOCK_HZ (15 * 1000 * 1000)
#define EXAMPLE_LCD_BK_LIGHT_ON_LEVEL 1
#define EXAMPLE_LCD_BK_LIGHT_OFF_LEVEL !EXAMPLE_LCD_BK_LIGHT_ON_LEVEL
#define EXAMPLE_PIN_NUM_BK_LIGHT 1
#define EXAMPLE_PIN_NUM_HSYNC 47
#define EXAMPLE_PIN_NUM_VSYNC 48
#define EXAMPLE_PIN_NUM_DE 45
#define EXAMPLE_PIN_NUM_PCLK 21
//D1-D11,D13-D17
//D0x D12x
#define EXAMPLE_PIN_NUM_DATA0 36 // B0
#define EXAMPLE_PIN_NUM_DATA1 37 // B1
#define EXAMPLE_PIN_NUM_DATA2 38 // B2
#define EXAMPLE_PIN_NUM_DATA3 39// B3
#define EXAMPLE_PIN_NUM_DATA4 40// B4
#define EXAMPLE_PIN_NUM_DATA5 41// G0
#define EXAMPLE_PIN_NUM_DATA6 42// G1
#define EXAMPLE_PIN_NUM_DATA7 15// G2
#define EXAMPLE_PIN_NUM_DATA8 16// G3
#define EXAMPLE_PIN_NUM_DATA9 17// G4
#define EXAMPLE_PIN_NUM_DATA10 18 // G5
#define EXAMPLE_PIN_NUM_DATA11 10 // R0
#define EXAMPLE_PIN_NUM_DATA12 11 // R1
#define EXAMPLE_PIN_NUM_DATA13 12 // R2
#define EXAMPLE_PIN_NUM_DATA14 13 // R3
#define EXAMPLE_PIN_NUM_DATA15 14 // R4
#define EXAMPLE_PIN_NUM_DISP_EN -1
// The pixel number in horizontal and vertical
#define EXAMPLE_LCD_H_RES 240
#define EXAMPLE_LCD_V_RES 320
#if CONFIG_EXAMPLE_DOUBLE_FB
#define EXAMPLE_LCD_NUM_FB 2
#else
#define EXAMPLE_LCD_NUM_FB 1
#endif // CONFIG_EXAMPLE_DOUBLE_FB
#define EXAMPLE_LVGL_TICK_PERIOD_MS 1
// we use two semaphores to sync the VSYNC event and the LVGL task, to avoid potential tearing effect
#if CONFIG_EXAMPLE_AVOID_TEAR_EFFECT_WITH_SEM
SemaphoreHandle_t sem_vsync_end;
SemaphoreHandle_t sem_gui_ready;
#endif
extern void example_lvgl_demo_ui(lv_disp_t *disp);
static bool example_on_vsync_event(esp_lcd_panel_handle_t panel, const esp_lcd_rgb_panel_event_data_t *event_data, void *user_data)
{
BaseType_t high_task_awoken = pdFALSE;
#if CONFIG_EXAMPLE_AVOID_TEAR_EFFECT_WITH_SEM
if (xSemaphoreTakeFromISR(sem_gui_ready, &high_task_awoken) == pdTRUE) {
xSemaphoreGiveFromISR(sem_vsync_end, &high_task_awoken);
}
#endif
return high_task_awoken == pdTRUE;
}
static void example_lvgl_flush_cb(lv_disp_drv_t *drv, const lv_area_t *area, lv_color_t *color_map)
{
esp_lcd_panel_handle_t panel_handle = (esp_lcd_panel_handle_t) drv->user_data;
int offsetx1 = area->x1;
int offsetx2 = area->x2;
int offsety1 = area->y1;
int offsety2 = area->y2;
ESP_LOGI(TAG, "example_lvgl_flush_cb:%d,%d,%d,%d",offsetx1,offsetx2,offsety1,offsety2);
#if CONFIG_EXAMPLE_AVOID_TEAR_EFFECT_WITH_SEM
xSemaphoreGive(sem_gui_ready);
xSemaphoreTake(sem_vsync_end, portMAX_DELAY);
#endif
// pass the draw buffer to the driver
esp_lcd_panel_draw_bitmap(panel_handle, offsetx1, offsety1, offsetx2 + 1, offsety2 + 1, color_map);
lv_disp_flush_ready(drv);
}
static void example_increase_lvgl_tick(void *arg)
{
/* Tell LVGL how many milliseconds has elapsed */
lv_tick_inc(EXAMPLE_LVGL_TICK_PERIOD_MS);
}
void app_main(void)
{
static lv_disp_draw_buf_t disp_buf; // contains internal graphic buffer(s) called draw buffer(s)
static lv_disp_drv_t disp_drv; // contains callback functions
//
rgb_spi_init();
//
#if CONFIG_EXAMPLE_AVOID_TEAR_EFFECT_WITH_SEM
ESP_LOGI(TAG, "Create semaphores");
sem_vsync_end = xSemaphoreCreateBinary();
assert(sem_vsync_end);
sem_gui_ready = xSemaphoreCreateBinary();
assert(sem_gui_ready);
#endif
#if EXAMPLE_PIN_NUM_BK_LIGHT >= 0
ESP_LOGI(TAG, "Turn off LCD backlight");
gpio_config_t bk_gpio_config = {
.mode = GPIO_MODE_OUTPUT,
.pin_bit_mask = 1ULL << EXAMPLE_PIN_NUM_BK_LIGHT
};
ESP_ERROR_CHECK(gpio_config(&bk_gpio_config));
#endif
ESP_LOGI(TAG, "Install RGB LCD panel driver");
esp_lcd_panel_handle_t panel_handle = NULL;
esp_lcd_rgb_panel_config_t panel_config = {
.data_width = 16, // RGB565 in parallel mode, thus 16bit in width
.psram_trans_align = 64,
.num_fbs = EXAMPLE_LCD_NUM_FB,
#if CONFIG_EXAMPLE_USE_BOUNCE_BUFFER
.bounce_buffer_size_px = 10 * EXAMPLE_LCD_H_RES,
#endif
.clk_src = LCD_CLK_SRC_DEFAULT,
.disp_gpio_num = EXAMPLE_PIN_NUM_DISP_EN,
.pclk_gpio_num = EXAMPLE_PIN_NUM_PCLK,
.vsync_gpio_num = EXAMPLE_PIN_NUM_VSYNC,
.hsync_gpio_num = EXAMPLE_PIN_NUM_HSYNC,
.de_gpio_num = EXAMPLE_PIN_NUM_DE,
.data_gpio_nums = {
EXAMPLE_PIN_NUM_DATA0,
EXAMPLE_PIN_NUM_DATA1,
EXAMPLE_PIN_NUM_DATA2,
EXAMPLE_PIN_NUM_DATA3,
EXAMPLE_PIN_NUM_DATA4,
EXAMPLE_PIN_NUM_DATA5,
EXAMPLE_PIN_NUM_DATA6,
EXAMPLE_PIN_NUM_DATA7,
EXAMPLE_PIN_NUM_DATA8,
EXAMPLE_PIN_NUM_DATA9,
EXAMPLE_PIN_NUM_DATA10,
EXAMPLE_PIN_NUM_DATA11,
EXAMPLE_PIN_NUM_DATA12,
EXAMPLE_PIN_NUM_DATA13,
EXAMPLE_PIN_NUM_DATA14,
EXAMPLE_PIN_NUM_DATA15,
},
.timings = {
.pclk_hz = EXAMPLE_LCD_PIXEL_CLOCK_HZ,
.h_res = EXAMPLE_LCD_H_RES,
.v_res = EXAMPLE_LCD_V_RES,
// The following parameters should refer to LCD spec
.hsync_back_porch = 40,
.hsync_front_porch = 20,
.hsync_pulse_width = 1,
.vsync_back_porch = 8,
.vsync_front_porch = 4,
.vsync_pulse_width = 1,
.flags.pclk_active_neg = true,
},
.flags.fb_in_psram = true, // allocate frame buffer in PSRAM
};
ESP_ERROR_CHECK(esp_lcd_new_rgb_panel(&panel_config, &panel_handle));
ESP_LOGI(TAG, "Register event callbacks");
esp_lcd_rgb_panel_event_callbacks_t cbs = {
.on_vsync = example_on_vsync_event,
};
ESP_ERROR_CHECK(esp_lcd_rgb_panel_register_event_callbacks(panel_handle, &cbs, &disp_drv));
ESP_LOGI(TAG, "Initialize RGB LCD panel");
ESP_ERROR_CHECK(esp_lcd_panel_reset(panel_handle));
ESP_ERROR_CHECK(esp_lcd_panel_init(panel_handle));
#if EXAMPLE_PIN_NUM_BK_LIGHT >= 0
ESP_LOGI(TAG, "Turn on LCD backlight");
gpio_set_level(EXAMPLE_PIN_NUM_BK_LIGHT, EXAMPLE_LCD_BK_LIGHT_ON_LEVEL);
#endif
ESP_LOGI(TAG, "Initialize LVGL library");
lv_init();
lv_color_t *buf1 = NULL;
lv_color_t *buf2 = NULL;
#if CONFIG_EXAMPLE_DOUBLE_FB
ESP_LOGI(TAG, "Use frame buffers as LVGL draw buffers");
ESP_ERROR_CHECK(esp_lcd_rgb_panel_get_frame_buffer(panel_handle, 2, &buf1, &buf2));
// initialize LVGL draw buffers
lv_disp_draw_buf_init(&disp_buf, buf1, buf2, EXAMPLE_LCD_H_RES * EXAMPLE_LCD_V_RES);
#else
ESP_LOGI(TAG, "Allocate separate LVGL draw buffers from PSRAM");
buf1 = heap_caps_malloc(EXAMPLE_LCD_H_RES *50* sizeof(lv_color_t), MALLOC_CAP_INTERNAL);
assert(buf1);
buf2 = heap_caps_malloc(EXAMPLE_LCD_H_RES *50* sizeof(lv_color_t), MALLOC_CAP_INTERNAL);
assert(buf2);
// initialize LVGL draw buffers
lv_disp_draw_buf_init(&disp_buf, buf1, buf2, EXAMPLE_LCD_H_RES * 50);
#endif // CONFIG_EXAMPLE_DOUBLE_FB
ESP_LOGI(TAG, "Register display driver to LVGL");
lv_disp_drv_init(&disp_drv);
disp_drv.hor_res = EXAMPLE_LCD_H_RES;
disp_drv.ver_res = EXAMPLE_LCD_V_RES;
disp_drv.flush_cb = example_lvgl_flush_cb;
disp_drv.draw_buf = &disp_buf;
disp_drv.user_data = panel_handle;
#if CONFIG_EXAMPLE_DOUBLE_FB
disp_drv.full_refresh = true; // the full_refresh mode can maintain the synchronization between the two frame buffers
#endif
lv_disp_t *disp = lv_disp_drv_register(&disp_drv);
ESP_LOGI(TAG, "Install LVGL tick timer");
// Tick interface for LVGL (using esp_timer to generate 2ms periodic event)
const esp_timer_create_args_t lvgl_tick_timer_args = {
.callback = &example_increase_lvgl_tick,
.name = "lvgl_tick"
};
esp_timer_handle_t lvgl_tick_timer = NULL;
ESP_ERROR_CHECK(esp_timer_create(&lvgl_tick_timer_args, &lvgl_tick_timer));
ESP_ERROR_CHECK(esp_timer_start_periodic(lvgl_tick_timer, EXAMPLE_LVGL_TICK_PERIOD_MS * 1000));
ESP_LOGI(TAG, "Display LVGL Scatter Chart");
//example_lvgl_demo_ui(disp);
//lv_demo_widgets();
lv_demo_benchmark();
while (1) {
// raise the task priority of LVGL and/or reduce the handler period can improve the performance
vTaskDelay(pdMS_TO_TICKS(1));
// The task running lv_timer_handler should have lower priority than that running `lv_tick_inc`
lv_timer_handler();
}
}
二、说明
1、ESP32S3只支持RGB565，因此HX8347的17H寄存器必须设置为50h。
需要特别注意的是连线不是连续的，要跳过D12和D0连接剩余的16根线。
2、HX8347关于RGB的配置涉及4个寄存器31h,32h,33h,34h
Lcd_Write_REG(0x31,0x02); //RGB Interface(1) (VS+HS+DE) 进入RGB模式1
Lcd_Write_REG(0x32,0x00); //DPL:(08) HSPL(04)VSPL(02) EPL (01)好像必须设置0x00
Lcd_Write_REG(0x33,0x02); //瞎设的
Lcd_Write_REG(0x34,0x02); //瞎设的
3、这几个参数应该好好设一下的，现在用的是DEMO中缺省的
.hsync_back_porch = 40,
.hsync_front_porch = 20,
.hsync_pulse_width = 1,
.vsync_back_porch = 8,
.vsync_front_porch = 4,
.vsync_pulse_width = 1,
.flags.pclk_active_neg = true,
但是好像需要看懂下面这个图才能设，以后再研究吧
4、所用程序改自官方RGB demo程序。
