[资料]基于小凌派RK2206开发板的电子秤功能实现

秤是一种在生活中经常使用的测量工具，随着科学技术的发展，传统的机械结构的秤逐渐被淘汰，电子秤能够准确、快速的测量并且显示直观操作灵活方便等诸多优点备受人们的青睐。
和传统秤相比较，电子秤利用新型传感器、高精度AD转换器件、单片机设计实现，具有精度高、功能强等特点。该电子秤的测量范围为0-5Kg，测量精度达到1g，有高精度，低成本的特点。电子秤采用液晶显示汉字和数值，比传统秤具有更高的准确性和直观性。另外，该电子秤电路简单，使用寿命长，应用范围广。

系统由RK2206+Openharmony+2.4寸LCD显示模块+hx711ad模块+按键模块+5kg压力传感器构成。
部分相关软件代码

void HX711_GPIO_Init()

{

    PinctrlSet(HX711_DOUT, MUX_FUNC0, PULL_UP, DRIVE_KEEP);

    LzGpioInit(HX711_DOUT);

    LzGpioSetDir(HX711_DOUT, LZGPIO_DIR_IN);

    LOS_Msleep(10);

 

    PinctrlSet(HX711_SCK, MUX_FUNC0, PULL_KEEP, DRIVE_KEEP);

    LzGpioInit(HX711_SCK);

    LzGpioSetDir(HX711_SCK, LZGPIO_DIR_OUT);

    LOS_Msleep(10);

}

 

uint32_t HX711_Read(void) //增益128

{

    uint32_t count;

    uint8_t  i;

    uint8_t  val;

    HX711_SCK_L();

    count = 0;

 

    uint_tick ts = get_current_tick();

    do{

        LzGpioGetVal(HX711_DOUT, &val);

    }while (val && get_time_us(ts) < 500000);

 

    for (i = 0; i < 24; i++)

    {

        HX711_SCK_H();

        count = count << 1;

        HX711_SCK_L();

        LzGpioGetVal(HX711_DOUT, &val);

        if (val)

            count++;

    }

    HX711_SCK_H();

    count = count ^ 0x800000; //第25个脉冲下降沿来时，转换数据

    ToyUdelay(7);

    HX711_SCK_L();

    return (count);

}

 

uint32_t e53_es_get_adc_average(void)

{

    uint8_t  cnt;

    uint32_t val;

    uint64_t sum = 0;

    uint32_t min = -1;

    uint32_t max = 0;

 

    for (cnt = 0; cnt < 5; cnt++)

    {

        val = HX711_Read();

        sum += val;

        if (val > max)

            max = val;

        if (val < min)

            min = val;

    }

    return (sum - max - min) / (cnt-2);

}

 

float e53_es_get_weight(float w, uint32_t peel_w, float percision)

{

    float weight = ES_GET_WEIGHT_VAL(HX711_Read(), peel_w); //通过公式将ad值转换为重量值

    

    if(percision == 0.0) percision = 0.01;

 

    if (abs(w - weight) < percision)  //浮动小于percision不改变值

    {

        weight = w;

    }

    if (weight < 0 || weight > 10000.0)

    {

        weight = 0;

    }

 

    return weight;

}

 

unsigned int lcd_init(uint8_t dir)

{ 

    static bool init = false;

    if(!init)

    {

        init = true;

        if (LOS_SemCreate(1, &m_sem_lcd) != LOS_OK)

        {

            init = false;

            printf("\n\n%s Falied to create Semaphore!!!\n\n", __FUNCTION__);

        }

    }

    /* 重启lcd */

    LCD_RES_Clr();

    LOS_Msleep(100);

    LCD_RES_Set();

    LOS_Msleep(100);

    LOS_Msleep(500);

    lcd_wr_reg(0x11);

    /* 等待LCD 100ms */

    LOS_Msleep(100);

    /* 启动LCD配置，设置显示和颜色配置 */

    lcd_wr_reg(0X36);

 

    switch (dir)

    {

    case 0:

        g_lcd_size.w = LCD_W;

        g_lcd_size.h = LCD_H;

        lcd_wr_data8(0x00);

        break;

    case 1:

        g_lcd_size.w = LCD_W;

        g_lcd_size.h = LCD_H;

        lcd_wr_data8(0xC0);

        break;   

    case 2:

        g_lcd_size.w = LCD_H;

        g_lcd_size.h = LCD_W;

        lcd_wr_data8(0x70);

        break;

    default:

        g_lcd_size.w = LCD_H;

        g_lcd_size.h = LCD_W;

        lcd_wr_data8(0xA0);

        break;

    }

 

    lcd_wr_reg(0X3A);

    lcd_wr_data8(0X05);

    /* ST7789S帧刷屏率设置 */

    lcd_wr_reg(0xb2);

    lcd_wr_data8(0x0c);

    lcd_wr_data8(0x0c);

    lcd_wr_data8(0x00);

    lcd_wr_data8(0x33);

    lcd_wr_data8(0x33);

    lcd_wr_reg(0xb7);

    lcd_wr_data8(0x35);

    /* ST7789S电源设置 */

    lcd_wr_reg(0xbb);

    lcd_wr_data8(0x35);

    lcd_wr_reg(0xc0);

    lcd_wr_data8(0x2c);

    lcd_wr_reg(0xc2);

    lcd_wr_data8(0x01);

    lcd_wr_reg(0xc3);

    lcd_wr_data8(0x13);

    lcd_wr_reg(0xc4);

    lcd_wr_data8(0x20);

    lcd_wr_reg(0xc6);

    lcd_wr_data8(0x0f);

    lcd_wr_reg(0xca);

    lcd_wr_data8(0x0f);

    lcd_wr_reg(0xc8);

    lcd_wr_data8(0x08);

    lcd_wr_reg(0x55);

    lcd_wr_data8(0x90);

    lcd_wr_reg(0xd0);

    lcd_wr_data8(0xa4);

    lcd_wr_data8(0xa1);

    /* ST7789S gamma设置 */

    lcd_wr_reg(0xe0);

    lcd_wr_data8(0xd0);

    lcd_wr_data8(0x00);

    lcd_wr_data8(0x06);

    lcd_wr_data8(0x09);

    lcd_wr_data8(0x0b);

    lcd_wr_data8(0x2a);

    lcd_wr_data8(0x3c);

    lcd_wr_data8(0x55);

    lcd_wr_data8(0x4b);

    lcd_wr_data8(0x08);

    lcd_wr_data8(0x16);

    lcd_wr_data8(0x14);

    lcd_wr_data8(0x19);

    lcd_wr_data8(0x20);

    lcd_wr_reg(0xe1);

    lcd_wr_data8(0xd0);

    lcd_wr_data8(0x00);

    lcd_wr_data8(0x06);

    lcd_wr_data8(0x09);

    lcd_wr_data8(0x0b);

    lcd_wr_data8(0x29);

    lcd_wr_data8(0x36);

    lcd_wr_data8(0x54);

    lcd_wr_data8(0x4b);

    lcd_wr_data8(0x0d);

    lcd_wr_data8(0x16);

    lcd_wr_data8(0x14);

    lcd_wr_data8(0x21);

    lcd_wr_data8(0x20);

    lcd_wr_reg(0x29);

    

    return 0;

}

 

void e53_es_thread(uint32_t args)

{

    float w = 0, last_w = 0;

    uint32_t *flag = (uint32_t *)args;

    e53_es_init(*flag);

 

    m_c12.peel.flag = false;

    m_c12.add.flag  = false;

    m_c12.dec.flag  = false;

    m_c12.add.w     = 0;

    m_c12.dec.w     = 0;

    m_c12.init_peel = e53_es_get_adc_average();

    m_c12.peel.w    = m_c12.init_peel;

    m_c12.lcd_msg.e53_c12.data.peel_w = ES_GET_WEIGHT_VAL(m_c12.peel.w , m_c12.init_peel);

 

    while (1)

    {  

        if(m_c12.add.flag)

        {

            m_c12.lcd_msg.e53_c12.data.weight -= m_c12.add.w;

        }

        else if(m_c12.dec.flag)

        {

            m_c12.lcd_msg.e53_c12.data.weight += m_c12.weight;

        }

 

        m_c12.weight = e53_es_get_weight(m_c12.lcd_msg.e53_c12.data.weight, m_c12.peel.w, 0.01);

 

        if(m_c12.add.flag)

        {

            m_c12.lcd_msg.e53_c12.data.weight = m_c12.add.w+m_c12.weight;

        }

        else if(m_c12.dec.flag)

        {

            m_c12.lcd_msg.e53_c12.data.weight = m_c12.dec.w-m_c12.weight;

        }

        else

        {

            m_c12.lcd_msg.e53_c12.data.weight = m_c12.weight;

        }

 

        m_c12.lcd_msg.e53_c12.data.peel_flag = m_c12.peel.flag;

        m_c12.lcd_msg.e53_c12.data.add_flag  = m_c12.add.flag;

        m_c12.lcd_msg.e53_c12.data.dec_flag  = m_c12.dec.flag;

        if(last_w != m_c12.lcd_msg.e53_c12.data.weight)

        {

            if(m_c12.add.flag)

            {

                printf("add:%f,%.0f\n", m_c12.add.w, m_c12.weight);             

            }

            else if(m_c12.dec.flag)

            {

                printf("dec:%f,%.0f\n", m_c12.dec.w, m_c12.weight);

            }

            printf("weight:%6.1f,peel:%6.1f\n", m_c12.lcd_msg.e53_c12.data.weight, m_c12.lcd_msg.e53_c12.data.peel_w);

        }

        last_w = m_c12.lcd_msg.e53_c12.data.weight;

        e53_c12_msg_send(&m_c12);

    }

}

 

void e53_es_example()

{

    unsigned int ret = LOS_OK;

    unsigned int thread_id;

    TSK_INIT_PARAM_S task = {0};

    task.pfnTaskEntry = (TSK_ENTRY_FUNC)e53_es_thread;

    task.uwStackSize = 10240;

    task.pcName = "e53_es_example";

    task.usTaskPrio = 2;

    ret = LOS_TaskCreate(&thread_id, &task);

    if (ret != LOS_OK)

    {

        printf("Falied to create e53_es_example ret:0x%x\n", ret);

        return;

    }

}

 

APP_FEATURE_INIT(e53_es_example);

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