LCD屏顯示實(shí)現(xiàn)觸摸功能

驅(qū)動(dòng)320* 240 ST7789的SPI屏幕進(jìn)行內(nèi)容顯示，顯示文字和觸控屏的基本使用；參考了:驅(qū)動(dòng)模型中定義了可供上層應(yīng)用調(diào)用的關(guān)鍵接口，如 讀/寫framebuffer 、開/關(guān)觸控動(dòng)作的操作畫面 、獲取屏幕設(shè)備信息 、 設(shè)置亮度/對(duì)比度/像素格式/方向等。

下圖為觸控屏的四個(gè)觸控開/關(guān)四個(gè)電機(jī)的“按鍵”

圖一（上電開機(jī)后顯示）

圖二（1號(hào)電機(jī)工作）

圖三（2號(hào)電機(jī)工作）

圖四（3號(hào)電機(jī)工作）

圖五（4號(hào)電機(jī)工作）

圖六（等待操作的狀態(tài)）

顯示觸控屏的常用API接口 ：

void display_get_capabilities(const struct device *dev, struct display_capabilities *capabilities)

參數(shù)說明

圖七

顯示屏設(shè)備樹配置

&csk6002_9s_nano_pinctrl{
            ...
            /* 顯示屏SPI接口配置 */
            pinctrl_spi0_sclk_default: spi0_sclk_default {
                    pinctrls = < &pinmuxa 15 6 >;
            };
            pinctrl_spi0_mosi_default: spi0_mosi_default {
                    pinctrls = < &pinmuxa 10 6 >;
            };
            pinctrl_spi0_miso_default: spi0_miso_default {
                    pinctrls = < &pinmuxa 17 6 >;
            };
            pinctrl_spi0_cs_default: spi0_cs_default {
                    pinctrls = < &pinmuxa 12 6 >;
            }; 
};

觸摸屏設(shè)備樹配置

用到引腳：i2c0_scl(pb2)、i2c0_sda(pb3)。

在 csk6011a_nano.overlay中完成外設(shè)接口的配置，具體實(shí)現(xiàn)如下：

在app/boards/目錄下的csk6002_9s_nano.overlay文件并添加如下設(shè)備樹配置：

圖八

&csk6002_9s_nano_pinctrl{
   // ...
    /* 觸摸屏I2C接口配置 */
    pinctrl_i2c0_scl_default: i2c0_scl_default{
            pinctrls = <&pinmuxb 2 8>;
    };
    
    pinctrl_i2c0_sda_default: i2c0_sda_default{
            pinctrls = <&pinmuxb 3 8>;
    }; 
};

&i2c0 {
        status = "okay";
        pinctrl-0 = <&pinctrl_i2c0_scl_default &pinctrl_i2c0_sda_default>; 
        pinctrl-names = "default";
        ft5336@0 {
                compatible = "focaltech,ft5336";
                reg = <0x38>;
                label = "FT5336";
                status = "okay";
                int-gpios = <&gpioa 3 0>;
        };
};

日志串口設(shè)備樹配置

本示例中將SDK默認(rèn)的日志串口(GPIOA_2、GPIOA_3)中的GPIOA_3復(fù)用為觸控屏的int使能腳，因此將日志輸出串口配置為GPIOb_10 、GPIOb_11，具體如下：

&csk6002_9s_nano_pinctrl{  
            /* 日志串口配置 */
            pinctrl_uart0_rx_default: uart0_rx_default{
                    pinctrls = <&pinmuxb 10 2>;
            };
            
            pinctrl_uart0_tx_default: uart0_tx_default{
                    pinctrls = <&pinmuxb 11 2>;
            };
            ...
};

觸摸屏組件配置

在prj.conf文件中打開觸摸屏功能配置:

觸摸配置

CONFIG_KSCAN=y

I2C功能配置

CONFIG_I2C=y

觸摸屏屏驅(qū)動(dòng)配置

CONFIG_KSCAN_BL6XXX=y

顯示屏組件配置

在prj.conf文件中打開顯示屏功能配置:

CONFIG_HEAP_MEM_POOL_SIZE=16384
CONFIG_LOG=y

GPIO功能配置

CONFIG_GPIO=y

顯示功能配置

CONFIG_DISPLAY=y

spi功能配置

CONFIG_SPI=y

ST7789V顯示屏驅(qū)動(dòng)配置

CONFIG_ST7789V=y

LCD屏顯示實(shí)現(xiàn)

void main(void)
{
    size_t x;
    size_t y;
    size_t rect_w;
    size_t rect_h;
    size_t h_step;
    size_t scale;
    size_t grey_count;
    uint8_t *buf;
    int32_t grey_scale_sleep;
    const struct device *display_dev;
    struct display_capabilities capabilities;
    struct display_buffer_descriptor buf_desc;
    size_t buf_size = 0;
    fill_buffer fill_buffer_fnc = NULL;

    LOG_INF("Display sample for %s", DISPLAY_DEV_NAME);
    
    /* kscan初始化 */
    kscan_init();
    
    /* 獲取display設(shè)備實(shí)例 */
    display_dev = device_get_binding(DISPLAY_DEV_NAME);

    if (display_dev == NULL) {
        LOG_ERR("Device %s not found. Aborting sample.",
            DISPLAY_DEV_NAME);
        RETURN_FROM_MAIN(1);
    }
    
    /* 獲取顯示功能 */
    display_get_capabilities(display_dev, &capabilities);

    if (capabilities.screen_info & SCREEN_INFO_MONO_VTILED) {
        rect_w = 32;
        rect_h = 10;
    } else {
        rect_w = 2;
        rect_h = 1;
    }

    h_step = rect_h;
    scale = (capabilities.x_resolution / 8) / rect_h;

    rect_w *= scale;
    rect_h *= scale;

    if (capabilities.screen_info & SCREEN_INFO_EPD) {
        grey_scale_sleep = 10000;
    } else {
        grey_scale_sleep = 100;
    }

    buf_size = rect_w * rect_h;

    if (buf_size < (capabilities.x_resolution * h_step)) {
        buf_size = capabilities.x_resolution * h_step;
    }
    
    /* 色塊配置 */
    switch (capabilities.current_pixel_format) {
    case PIXEL_FORMAT_ARGB_8888:
        fill_buffer_fnc = fill_buffer_argb8888;
        buf_size *= 4;
        break;
    case PIXEL_FORMAT_RGB_888:
        fill_buffer_fnc = fill_buffer_rgb888;
        buf_size *= 3;
        break;
    case PIXEL_FORMAT_RGB_565:
        fill_buffer_fnc = fill_buffer_rgb565;
        buf_size *= 2;
        break;
    case PIXEL_FORMAT_BGR_565:
        fill_buffer_fnc = fill_buffer_bgr565;
        buf_size *= 2;
        break;
    case PIXEL_FORMAT_MONO01:
    case PIXEL_FORMAT_MONO10:
        fill_buffer_fnc = fill_buffer_mono;
        buf_size /= 8;
        break;
    default:
        LOG_ERR("Unsupported pixel format. Aborting sample.");
        RETURN_FROM_MAIN(1);
    }

    buf = k_malloc(buf_size);

    if (buf == NULL) {
        LOG_ERR("Could not allocate memory. Aborting sample.");
        RETURN_FROM_MAIN(1);
    }
    
    (void)memset(buf, 0xFFu, buf_size);

    buf_desc.buf_size = buf_size;
    buf_desc.pitch = capabilities.x_resolution;
    buf_desc.width = capabilities.x_resolution;
    buf_desc.height = h_step;

    /*整屏填充白色背景*/
    for (int idx = 0; idx < capabilities.y_resolution; idx += h_step) {
        display_write(display_dev, 0, idx, &buf_desc, buf);
    }

    /*左上角填充紅色塊*/
    fill_buffer_fnc(TOP_LEFT, 0, buf, buf_size);
    x = 0;
    y = 0;
    display_write(display_dev, x, y, &buf_desc, buf);

    /*右上角填充綠色塊*/
    fill_buffer_fnc(TOP_RIGHT, 0, buf, buf_size);
    x = capabilities.x_resolution - rect_w;
    y = 0;
    display_write(display_dev, x, y, &buf_desc, buf);

    /*右下角填充藍(lán)色塊*/
    fill_buffer_fnc(BOTTOM_RIGHT, 0, buf, buf_size);
    x = capabilities.x_resolution - rect_w;
    y = capabilities.y_resolution - rect_h;
    display_write(display_dev, x, y, &buf_desc, buf);
    
    /* 關(guān)閉顯示消隱 */
    display_blanking_off(display_dev);

    grey_count = 0;
    x = 0;
    y = capabilities.y_resolution - rect_h;

    /*左下角灰色動(dòng)態(tài)色塊*/
    while (1) {
        fill_buffer_fnc(BOTTOM_LEFT, grey_count, buf, buf_size);
        display_write(display_dev, x, y, &buf_desc, buf);
        ++grey_count;
        k_msleep(grey_scale_sleep);
    }
}

觸摸屏功能實(shí)現(xiàn)

Zephyr具備kscan（keyboard scan matrix）驅(qū)動(dòng)模型，其驅(qū)動(dòng)程序用于檢測(cè)矩陣鍵盤或帶有按鈕的設(shè)備中的按鍵（用戶觸碰觸摸屏本質(zhì)上是生成一個(gè)行列坐標(biāo)）。查閱zephyr官網(wǎng)Display Interface。

圖九

注冊(cè)callback函數(shù)

/* 觸摸回調(diào)函數(shù)，打印坐標(biāo) */
static void k_callback(const struct device *dev, uint32_t row, uint32_t col,
               bool pressed)
{
    ARG_UNUSED(dev);
    printk("row = %u col = %u, pressed:%s\\n", row, col, pressed ? "TRUE" : "FLASE");
}

void kscan_init(void)
{   
    /* 獲取kscan設(shè)備實(shí)例 */
    const struct device *kscan_dev = device_get_binding(DISPLAY_KSAN_DEV_NAME);

    if (!device_is_ready(kscan_dev)) {
        LOG_ERR("kscan device %s not ready", kscan_dev->name);
        return;
    }
    
    /* 注冊(cè)回調(diào)，在k_callback中可看到對(duì)應(yīng)的坐標(biāo)與狀態(tài)printk輸出操作 */
    kscan_config(kscan_dev, k_callback);
    /* 使能回調(diào) */
    kscan_enable_callback(kscan_dev);
}

void main(void)
{
    kscan_init();
    ...
}

編譯的指令是：

lisa zep build

燒錄的指令是：

lisa zep flash

結(jié)果

觸控屏顯示了四個(gè)觸控開關(guān)符，分別觸摸對(duì)應(yīng)顯示在（LED1符 LED2符 LED3符 LED4符的下面觸控開關(guān)）。四個(gè)功能（GPIO） PWM 控制電機(jī)運(yùn)行，后面補(bǔ)上（高發(fā)性的疫情過后，回公司上班補(bǔ)上，焊接上電機(jī)驅(qū)動(dòng)板）。我們開發(fā)了一個(gè)PC上位機(jī)軟件（視覺圖分析用）。GC032A攝像頭上傳的圖像以后可以在觸控屏顯（一個(gè)靜態(tài)圖）。

圖十

審核編輯：劉清