stc8h8k64u电压表的代码

以下是使用STC8H8K64U单片机实现的电压表代码：

#include <REGSTC8.H>

// 定义ADC通道
#define ADC_CHANNEL 5

// 定义LCD引脚
sbit LCD_RS = P0^0;
sbit LCD_RW = P0^1;
sbit LCD_E = P0^2;
sbit LCD_D4 = P0^4;
sbit LCD_D5 = P0^5;
sbit LCD_D6 = P0^6;
sbit LCD_D7 = P0^7;

// 声明函数
void delay(unsigned int time);
void LCD_Init();
void LCD_Display(unsigned char x,unsigned char y,unsigned char *data);
void ADC_Init();
unsigned int ADC_Read(unsigned char channel);

void main()
{
    unsigned int adc_value;
    unsigned char temp[16];

    // 初始化LCD
    LCD_Init();

    // 初始化ADC
    ADC_Init();

    while(1)
    {
        // 读取ADC值
        adc_value = ADC_Read(ADC_CHANNEL);

        // 将ADC值转换为电压值，假设ADC参考电压为5V
        float voltage = (float)adc_value / 1023 * 5;

        // 将电压值转换为字符串
        sprintf(temp, "Voltage:%.2fV", voltage);

        // 在LCD上显示电压值
        LCD_Display(0,0,temp);

        // 延时一段时间
        delay(1000);
    }
}

// 延时函数
void delay(unsigned int time)
{
    unsigned int i,j;
    for(i=0;i<time;i++)
        for(j=0;j<120;j++);
}

// LCD初始化函数
void LCD_Init()
{
    LCD_RS = 0;
    LCD_RW = 0;
    LCD_E = 0;
    delay(50);
    LCD_E = 1;
    LCD_D4 = 0;
    LCD_D5 = 0;
    LCD_D6 = 1;
    LCD_D7 = 1;
    LCD_E = 0;
    delay(5);
    LCD_E = 1;
    LCD_E = 0;
    delay(5);
    LCD_E = 1;
    LCD_E = 0;
    delay(5);
    LCD_D4 = 0;
    LCD_D5 = 0;
    LCD_D6 = 1;
    LCD_D7 = 0;
    LCD_E = 1;
    LCD_E = 0;
    delay(5);
    LCD_Display(0,0,"Voltage:");
}

// LCD显示函数
void LCD_Display(unsigned char x,unsigned char y,unsigned char *data)
{
    unsigned char i;
    if(x<16)
    {
        if(y) x|=0x40;
        x|=0x80;
        LCD_RS=0;
        LCD_RW=0;
        delay(1);
        LCD_E=1;
        delay(1);
        LCD_D7=0;
        for(i=0;i<8;i++)
        {
            LCD_D6=(x>>7);
            x<<=1;
            LCD_E=0;
            delay(1);
            LCD_E=1;
            delay(1);
        }
        LCD_RS=1;
        for(i=0;i<strlen(data);i++)
        {
            LCD_D7=(data[i]&0x80);
            LCD_D6=(data[i]&0x40);
            LCD_D5=(data[i]&0x20);
            LCD_D4=(data[i]&0x10);
            LCD_E=0;
            delay(1);
            LCD_E=1;
            delay(1);
            LCD_D7=(data[i]&0x08);
            LCD_D6=(data[i]&0x04);
            LCD_D5=(data[i]&0x02);
            LCD_D4=(data[i]&0x01);
            LCD_E=0;
            delay(1);
            LCD_E=1;
            delay(1);
        }
    }
}

// ADC初始化函数
void ADC_Init()
{
    P1ASF = 0x20; // 将P1.5设置为模拟输入口
    ADC_RES = 0;
    ADC_CONTR = ADC_POWER | ADC_SPEEDLL | ADC_START | ADC_CHANNEL;
}

// ADC读取函数
unsigned int ADC_Read(unsigned char channel)
{
    ADC_CONTR = ADC_POWER | ADC_SPEEDLL | ADC_START | channel;
    _nop_();
    _nop_();
    _nop_();
    _nop_();
    while(!(ADC_CONTR & ADC_FLAG));
    ADC_CONTR &= ~ADC_FLAG;
    return ((unsigned int)ADC_RES << 2) | ADC_RESL;
}

这段代码使用了STC8H8K64U单片机的ADC模块，将P1.5设置为模拟输入口，并通过LCD显示电压值。需要注意的是，这里假设ADC参考电压为5V，如果实际参考电压不同，需要相应地调整电压转换的公式。