ds1302驱动程序

DS1302是一款实时时钟芯片，常用于嵌入式系统中。下面是一个简单的DS1302驱动程序的示例代码，仅供参考：

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <wiringPi.h>

#define DS1302_SCLK_PIN  2
#define DS1302_IO_PIN    3
#define DS1302_CE_PIN    4

#define DS1302_SEC_REG   0x80
#define DS1302_MIN_REG   0x82
#define DS1302_HOUR_REG  0x84
#define DS1302_DATE_REG  0x86
#define DS1302_MONTH_REG 0x88
#define DS1302_DAY_REG   0x8A
#define DS1302_YEAR_REG  0x8C

void DS1302Init()
{
    pinMode(DS1302_SCLK_PIN, OUTPUT);
    pinMode(DS1302_IO_PIN, OUTPUT);
    pinMode(DS1302_CE_PIN, OUTPUT);

    digitalWrite(DS1302_CE_PIN, LOW);
    digitalWrite(DS1302_SCLK_PIN, LOW);
}

void DS1302WriteByte(unsigned char addr, unsigned char data)
{
    unsigned char i;

    digitalWrite(DS1302_CE_PIN, LOW);
    delayMicroseconds(2);

    for (i = 0; i < 8; i++)
    {
        digitalWrite(DS1302_IO_PIN, addr & 0x01);
        addr >>= 1;
        digitalWrite(DS1302_SCLK_PIN, HIGH);
        delayMicroseconds(2);
        digitalWrite(DS1302_SCLK_PIN, LOW);
        delayMicroseconds(2);
    }

    for (i = 0; i < 8; i++)
    {
        digitalWrite(DS1302_IO_PIN, data & 0x01);
        data >>= 1;
        digitalWrite(DS1302_SCLK_PIN, HIGH);
        delayMicroseconds(2);
        digitalWrite(DS1302_SCLK_PIN, LOW);
        delayMicroseconds(2);
    }

    digitalWrite(DS1302_CE_PIN, HIGH);
}

unsigned char DS1302ReadByte(unsigned char addr)
{
    unsigned char i, data = 0;

    digitalWrite(DS1302_CE_PIN, LOW);
    delayMicroseconds(2);

    for (i = 0; i < 8; i++)
    {
        digitalWrite(DS1302_IO_PIN, addr & 0x01);
        addr >>= 1;
        digitalWrite(DS1302_SCLK_PIN, HIGH);
        delayMicroseconds(2);
        digitalWrite(DS1302_SCLK_PIN, LOW);
        delayMicroseconds(2);
    }

    pinMode(DS1302_IO_PIN, INPUT);
    delayMicroseconds(2);

    for (i = 0; i < 8; i++)
    {
        data >>= 1;
        if (digitalRead(DS1302_IO_PIN))
        {
            data |= 0x80;
        }
        digitalWrite(DS1302_SCLK_PIN, HIGH);
        delayMicroseconds(2);
        digitalWrite(DS1302_SCLK_PIN, LOW);
        delayMicroseconds(2);
    }

    pinMode(DS1302_IO_PIN, OUTPUT);
    digitalWrite(DS1302_CE_PIN, HIGH);

    return data;
}

void DS1302WriteTime(unsigned char sec, unsigned char min, unsigned char hour,
                     unsigned char date, unsigned char month, unsigned char day, unsigned char year)
{
    DS1302WriteByte(DS1302_SEC_REG, sec);
    DS1302WriteByte(DS1302_MIN_REG, min);
    DS1302WriteByte(DS1302_HOUR_REG, hour);
    DS1302WriteByte(DS1302_DATE_REG, date);
    DS1302WriteByte(DS1302_MONTH_REG, month);
    DS1302WriteByte(DS1302_DAY_REG, day);
    DS1302WriteByte(DS1302_YEAR_REG, year);
}

void DS1302ReadTime(unsigned char *sec, unsigned char *min, unsigned char *hour,
                    unsigned char *date, unsigned char *month, unsigned char *day, unsigned char *year)
{
    *sec = DS1302ReadByte(DS1302_SEC_REG);
    *min = DS1302ReadByte(DS1302_MIN_REG);
    *hour = DS1302ReadByte(DS1302_HOUR_REG);
    *date = DS1302ReadByte(DS1302_DATE_REG);
    *month = DS1302ReadByte(DS1302_MONTH_REG);
    *day = DS1302ReadByte(DS1302_DAY_REG);
    *year = DS1302ReadByte(DS1302_YEAR_REG);
}

int main()
{
    unsigned char sec, min, hour, date, month, day, year;

    wiringPiSetup();

    DS1302Init();

    DS1302WriteTime(0x00, 0x00, 0x12, 0x01, 0x01, 0x01, 0x21); // 设置初始时间为 2021-01-01 12:00:00
    while (1)
    {
        DS1302ReadTime(&sec, &min, &hour, &date, &month, &day, &year);
        printf("%02x:%02x:%02x %02x-%02x-%02x\n", hour, min, sec, year, month, date);
        delay(1000);
    }

    return 0;
}

这是一个基于wiringPi库的程序，使用树莓派的GPIO口与DS1302连接。主程序循环读取实时时钟的时间，并输出到终端。注意，DS1302使用的是BCD码表示时间，需要进行转换才能正确显示。