RGB565 LCD

1 Introduction

RGB565 project is verified RGB565 interface display function,randoms color are displayed every second after power on

the main differences of RGB888/RGB565/RGB666 project is whether the screen supports RGB565 or rgb666 or rgb888, the data source is not mandatory ,it can be RGB565, RGB888 or YUYV.

2 Code Path

demo path:./projects/peripheral/lcd_rgb565

3.Code explanation

compile commands:make bk7258 PROJECT=peripheral/lcd_rgb565

Attention

LCD RGB565 or RGB666 or RGB888 is defined by lcd_device_t member “out_fmt”, alse can config by API:

LCD conifig by default:

const lcd_device_t lcd_device_st7701sn =
{
        .id = LCD_DEVICE_ST7701SN,
        .name = "st7701sn",
        .type = LCD_TYPE_RGB565,    /**< lcd device hw interface *LCD_TYPE_RGB=LCD_TYPE_RGB565 */
        .ppi = PPI_480X854,
        .rgb = &lcd_rgb,
        .src_fmt = PIXEL_FMT_RGB565,   /**< source data format: input to display module data format(rgb565/rgb888/yuv)*/
        .out_fmt = PIXEL_FMT_RGB565, /**< display module output data format(rgb565/rgb666/rgb888), input to lcd device,*/
        .init = lcd_st7701sn_init,
        .lcd_off = NULL,
};

user can also use API to config:

lcd_hal_rgb_set_in_out_format(src_fmt, out_fmt);

RGB565 LCD config step

step 1: open lcd

media_app_lcd_pipeline_disp_open
media_app_lcd_example_display

step 2:malloc psram

frame_buffer_display_malloc

after psram malloc, should config frame:

uint32_t size = ppi_to_pixel_x(lcd_open->device_ppi) * ppi_to_pixel_y(lcd_open->device_ppi) * 2;

frame = frame_buffer_display_malloc(size);

frame->width = ppi_to_pixel_x(lcd_open->device_ppi);
frame->height = ppi_to_pixel_y(lcd_open->device_ppi);
frame->fmt = PIXEL_FMT_RGB565;

step 3:fill color

lcd_fill_rand_color

step 4:display request

lcd_display_frame_request

step 5:cycle step2-4