ds1302op.c

时钟芯片ds1302 程序 源程序按版本号放在文件夹中。里面有在Protues中仿真的DSN文件。 打开MPLAB的MCP文件进行编译 将DSN文件载入Protues中 将生成的HEX导入到P

#include "DS1302op.h"

//When read data, the tris bit should be 1, and 0 for write
#define ReadData    1
#define WriteData   0

//after right shift the CMDByte (include carry bit) 8 times
// the bit0 change to bit1
//so I use the bit1 to judge whether it's a read command or not
#define IsReadOP(x)  x&0x02

//define a global variable, so that the data transfer between 
//the functions will be faster
//and can make the asm code easier
//unsigned char DataAll;  //Transfer data between the inner function

unsigned char DataTemp; //Temp byte for one-byte-write command
unsigned char MyINDF @ 0x00;

//declare an inner function, read and write a byte
//before use the write function
//Make sure the clock bit is low and the RST bit is high
void    WriteByte2();

//Operation of the DS1302
//Require data address,length and the command you want to send
unsigned char OperateDS(unsigned char ptr ,
unsigned char DataLen,unsigned char CMDByte)
{
        unsigned char i;
        DS_RST=0;
        DataDir=WriteData;
        DS_RST=1;
        asm("movwf _FSR");
        WriteByte2();
        if(IsReadOP(CMDByte))
        {
            //Read operation
            DataDir=ReadData;
            do{
                i=8;
                do
                {
                    DS_Clock=0;
                    MyINDF>>=1;
                    if(DS_Data)
                        MyINDF|=0x80;
                    DS_Clock=1;
                }while(--i);
                FSR++;
            }while(--DataLen);
        //*/
            DataTemp=DataTemp; //The return value for single byte read
        }
        else
        {
            //Write operation
            do{
                CMDByte=MyINDF;
                WriteByte2();
                FSR++;
            }while(--DataLen);
            //*/
        }
        DS_RST=0;
}
//inner function
void    WriteByte2()
//Make sure the clock bit is low and the RST bit is high
{
    unsigned char i=0x08;
    do
    {
        DS_Clock=0;
        DS_Data=0;
        //*
        //The first parameter of OperateDS is ptr, restored in w
        //The second one is DataLen, restored in ?_OperateDS+0
        //The third one is CMDByte, restored in ?_OperateDS+1 
        asm("BTFSC  ?_OperateDS+1,0");
        DS_Data=1;
        asm("rrf  ?_OperateDS+1,f");
        //*/
        DS_Clock=1;
    }while(--i);
}
//end inner function
//*/