【GD32450I-EVAL】移植触摸到LittleVGL

tinnu

【GD32450I-EVAL】移植触摸到LittleVGL [复制链接]

上一篇帖子进行了触摸驱动测试：SPI收发与触摸芯片XPT2046驱动及笔中断

接下来就是移植到 LittleVGL 。

上次移植完 LittleVGL 的显示时留下了一个：

static bool DEMO_ReadTouch(lv_indev_drv_t * indev_drv, lv_indev_data_t *data)

这个函数里面没有进行什么操作，这时候只需要添加触摸位置点进去即可。

static bool DEMO_ReadTouch(lv_indev_drv_t * indev_drv, lv_indev_data_t *data)
{
    static int touch_x = 0;
    static int touch_y = 0;
    uint16_t t_xx = 0, t_yy = 0;

    data->state = LV_INDEV_STATE_REL;


    if(gpio_input_bit_get(GPIOI, GPIO_PIN_3)==RESET)
    {
        ReadTPXYOver(&t_xx, &t_yy);
		t_yy = 4096-t_yy;
        touch_x = 480 * t_xx / 4096;
        touch_y = 272 * t_yy / 4096;
        touch_x -= 20;
        touch_y -= 30;
        if (touch_x<0 || touch_x > LCD_WIDTH){
			touch_x =0;
			touch_y =0;
		}
        else if (touch_y<0 || touch_y > LCD_HEIGHT){
			touch_x =0;
			touch_y =0;
		}
		else
			data->state = LV_INDEV_STATE_PR;
    }

    /*Set the last pressed coordinates*/
    data->point.x = touch_x;
    data->point.y = touch_y;

    /*Return `false` because we are not buffering and no more data to read*/
    return false;
}

因为RAM容量的原因，只能支持270*180宽度显示，因此必须换算实际触摸点与 LittleVGL 内的位置，因此程序里加入了：

        touch_x -= 20;
        touch_y -= 30;

其中X显示的时候向左偏移了20像素，Y偏移了30像素，具体可以看显示部分的移植。

 

ReadTPXYOver 函数是进行多次读取，经过冒泡排序后取中位数：

void ReadTPXY(uint16_t *t_x, uint16_t *t_y)
{
    char t_char[30] = "";
    gpio_bit_reset(GPIOF, GPIO_PIN_6);
    //X
    while (RESET == spi_i2s_flag_get(SPI3, SPI_FLAG_TBE));
    spi_i2s_data_transmit(SPI4, 0xD0);
    while (RESET == spi_i2s_flag_get(SPI4, SPI_FLAG_RBNE));
    spi_i2s_data_receive(SPI4);

	// delay_us(100);
    //read 1
    while (RESET == spi_i2s_flag_get(SPI3, SPI_FLAG_TBE));
    spi_i2s_data_transmit(SPI4, 0x00);
    while (RESET == spi_i2s_flag_get(SPI4, SPI_FLAG_RBNE));
    *t_x = spi_i2s_data_receive(SPI4);
    *t_x = (*t_x& 0x7F)<<8 ;
    //read2
    while (RESET == spi_i2s_flag_get(SPI3, SPI_FLAG_TBE));
    spi_i2s_data_transmit(SPI4, 0x90);
    while (RESET == spi_i2s_flag_get(SPI4, SPI_FLAG_RBNE));
    *t_x = *t_x|spi_i2s_data_receive(SPI4);

    // sprintf(t_char, "x:%x\t", *t_x);
    // PRINTF_UART0(t_char);

    *t_x = *t_x>>3;

	// delay_us(100);
    
    while (RESET == spi_i2s_flag_get(SPI3, SPI_FLAG_TBE));
    spi_i2s_data_transmit(SPI4, 0x00);
    while (RESET == spi_i2s_flag_get(SPI4, SPI_FLAG_RBNE));
    *t_y = spi_i2s_data_receive(SPI4);
    *t_y = (*t_y& 0x7F) <<8;

    while (RESET == spi_i2s_flag_get(SPI3, SPI_FLAG_TBE));
    spi_i2s_data_transmit(SPI4, 0x00);
    while (RESET == spi_i2s_flag_get(SPI4, SPI_FLAG_RBNE));
    *t_y = *t_y|spi_i2s_data_receive(SPI4);

    // sprintf(t_char, "y:%x\t", *t_y);
    // PRINTF_UART0(t_char);

    *t_y = *t_y>>3;
}

void ReadTPXYOver(uint16_t *t_x, uint16_t *t_y)

 

效果：

okhxyyo

兆易GD32450I-EVAL

汇总贴：https://bbs.eeworld.com.cn/thread-1140981-1-1.html

freebsder

这个好,给力!