//***************************************
// HMC5883 51ڲԳ
// ʹõƬSTC89C51 
// 11.0592M
// ʾPC
// 뻷 Keil uVision2
// ο꾧վ24c04ͨų
// ʱ䣺201131
//****************************************
#include  <REG51.H>	
#include  <math.h>    //Keil library  
#include  <stdio.h>   //Keil library	
#include  <INTRINS.H>
#define   uchar unsigned char
#define   uint  unsigned int	
//ʹõĶ˿ڣ밴½
#define DataPort P0	//LCD1602ݶ˿
sbit	SCL=P1^0;      //IICʱŶ
sbit	SDA=P1^1;      //IICŶ


#define	SlaveAddress   0x3C	  //5883IICеĴӵַ
typedef unsigned char BYTE;
typedef unsigned short WORD;

BYTE BUF[8];                         //ݻ      	
uchar ge,shi,bai,qian,wan;           //ʾ
int  dis_data;                       //
//************

//************
void delay(unsigned int k);
void Init_HMC5883(void);            //ʼ5883
void conversion(uint temp_data);

void  Single_Write_HMC5883(uchar REG_Address,uchar REG_data);   //д
//uchar Single_Read_HMC5883(uchar REG_Address);                   //ȡڲĴ
void  Multiple_Read_HMC5883();                                  //ĶȡڲĴ
//ģiicʹú-------------
void Delay5us();
void Delay5ms();
void HMC5883_Start();
void HMC5883_Stop();
void HMC5883_SendACK(bit ack);
bit  HMC5883_RecvACK();
void HMC5883_SendByte(BYTE dat);
BYTE HMC5883_RecvByte();
void HMC5883_ReadPage();
void HMC5883_WritePage();
//-----------------------------------

//*********************************************
//ڳʼ
//9600 bps @ 11.059 MHz 
void init_uart()
{
	TMOD=0x21;				
	TH1=0xfd;				
	TL1=0xfd;				
	SCON=0x50;
	PS=1;      //жΪȼ
	TR0=1;	   //ʱ			
	TR1=1;
	ET0=1;     //򿪶ʱ0ж			
	ES=1;	
}

//*********ݷ******************
void  SeriPushSend(uchar send_data)
{
    SBUF=send_data;  
	while(!TI);TI=0;	  
}
//*********************************************************
void conversion(uint temp_data)  
{  
    wan=temp_data/10000+0x30 ;
    temp_data=temp_data%10000;   //ȡ
	qian=temp_data/1000+0x30 ;
    temp_data=temp_data%1000;    //ȡ
    bai=temp_data/100+0x30   ;
    temp_data=temp_data%100;     //ȡ
    shi=temp_data/10+0x30    ;
    temp_data=temp_data%10;      //ȡ
    ge=temp_data+0x30; 	
}

/*******************************/
void delay(unsigned int k)	
{						
unsigned int i,j;				
for(i=0;i<k;i++)
{			
for(j=0;j<121;j++)			
{;}}						
}
	

/**************************************
ʱ5΢(STC90C52RC@12M)
ͬĹ,Ҫ˺עʱӹʱҪ޸
1TMCUʱ,ʱ
**************************************/
void Delay5us()
{
    _nop_();_nop_();_nop_();_nop_();
    _nop_();_nop_();_nop_();_nop_();
	_nop_();_nop_();_nop_();_nop_();
	_nop_();_nop_();_nop_();_nop_();
    _nop_();_nop_();_nop_();_nop_();
}

/**************************************
ʱ5(STC90C52RC@12M)
ͬĹ,Ҫ˺
1TMCUʱ,ʱ
**************************************/
void Delay5ms()
{
    WORD n = 560;

    while (n--);
}

/**************************************
ʼź
**************************************/
void HMC5883_Start()
{
    SDA = 1;                    //
    SCL = 1;                    //ʱ
    Delay5us();                 //ʱ
    SDA = 0;                    //½
    Delay5us();                 //ʱ
    SCL = 0;                    //ʱ
}

/**************************************
ֹͣź
**************************************/
void HMC5883_Stop()
{
    SDA = 0;                    //
    SCL = 1;                    //ʱ
    Delay5us();                 //ʱ
    SDA = 1;                    //
    Delay5us();                 //ʱ
}

/**************************************
Ӧź
ڲ:ack (0:ACK 1:NAK)
**************************************/
void HMC5883_SendACK(bit ack)
{
    SDA = ack;                  //дӦź
    SCL = 1;                    //ʱ
    Delay5us();                 //ʱ
    SCL = 0;                    //ʱ
    Delay5us();                 //ʱ
}

/**************************************
Ӧź
**************************************/
bit HMC5883_RecvACK()
{
    SCL = 1;                    //ʱ
    Delay5us();                 //ʱ
    CY = SDA;                   //Ӧź
    SCL = 0;                    //ʱ
    Delay5us();                 //ʱ

    return CY;
}

/**************************************
IIC߷һֽ
**************************************/
void HMC5883_SendByte(BYTE dat)
{
    BYTE i;

    for (i=0; i<8; i++)         //8λ
    {
        dat <<= 1;              //Ƴݵλ
        SDA = CY;               //ݿ
        SCL = 1;                //ʱ
        Delay5us();             //ʱ
        SCL = 0;                //ʱ
        Delay5us();             //ʱ
    }
    HMC5883_RecvACK();
}

/**************************************
IIC߽һֽ
**************************************/
BYTE HMC5883_RecvByte()
{
    BYTE i;
    BYTE dat = 0;

    SDA = 1;                    //ʹڲ,׼ȡ,
    for (i=0; i<8; i++)         //8λ
    {
        dat <<= 1;
        SCL = 1;                //ʱ
        Delay5us();             //ʱ
        dat |= SDA;             //               
        SCL = 0;                //ʱ
        Delay5us();             //ʱ
    }
    return dat;
}

//***************************************************

void Single_Write_HMC5883(uchar REG_Address,uchar REG_data)
{
    HMC5883_Start();                  //ʼź
    HMC5883_SendByte(SlaveAddress);   //豸ַ+дź
    HMC5883_SendByte(REG_Address);    //ڲĴַοpdf 
    HMC5883_SendByte(REG_data);       //ڲĴݣοpdf
    HMC5883_Stop();                   //ֹͣź
}
 /*
//********ֽڶȡڲĴ*************************
uchar Single_Read_HMC5883(uchar REG_Address)
{  uchar REG_data;
    HMC5883_Start();                          //ʼź
    HMC5883_SendByte(SlaveAddress);           //豸ַ+дź
    HMC5883_SendByte(REG_Address);                   //ʹ洢Ԫַ0ʼ	
    HMC5883_Start();                          //ʼź
    HMC5883_SendByte(SlaveAddress+1);         //豸ַ+ź
    REG_data=HMC5883_RecvByte();              //Ĵ
	HMC5883_SendACK(1);   
	HMC5883_Stop();                           //ֹͣź
    return REG_data; 
}
*/
//******************************************************
//
//HMC5883ڲǶݣַΧ0x3~0x5
//
//******************************************************
void Multiple_read_HMC5883(void)
{   uchar i;
    HMC5883_Start();                          //ʼź
    HMC5883_SendByte(SlaveAddress);           //豸ַ+дź
    HMC5883_SendByte(0x03);                   //ʹ洢Ԫַ0x3ʼ	
    HMC5883_Start();                          //ʼź
    HMC5883_SendByte(SlaveAddress+1);         //豸ַ+ź
	 for (i=0; i<7; i++)                      //ȡ6ַݣ洢BUF
    {
        BUF[i] = HMC5883_RecvByte();          //BUF[0]洢0x32ַе
        if (i == 6)
        {
           HMC5883_SendACK(1);                //һҪNOACK
        }
        else
        {
          HMC5883_SendACK(0);                //ӦACK
       }
   }
    HMC5883_Stop();                          //ֹͣź
    Delay5ms();
}

//ʼHMC5883Ҫοpdf޸****
void Init_HMC5883()
{
     Single_Write_HMC5883(0x02,0x00);  //
	 Single_Write_HMC5883(0x01,0xE0);  //
}
//*********************************************************
//********
//*********************************************************
void main()
{ // bit sign_bit;

   unsigned int i;
   int x,y,z;
   double angle;


   delay(100);			
   init_uart();
   Init_HMC5883();

  while(1)            //ѭ
  { 

    Multiple_Read_HMC5883();      //ݣ洢BUF
	x = BUF[0] << 8 | BUF[1]; 
    y = BUF[4] << 8 | BUF[5]; 
	z = BUF[2] << 8 | BUF[3]; 
    angle= atan2((double)y,(double)x) * (180 / 3.14159265) + 180; // angle in degrees
    conversion(angle);       //ݺʾ

    SeriPushSend(bai);
    SeriPushSend(shi);
	SeriPushSend(ge);

	SeriPushSend(0x0d);
	SeriPushSend(0x0a);

    for (i=0;i<10000;i++);   //ʱ                   
  }
} 

