max525.c

低功耗、四路、12位、电压输出DAC

//ICC-AVR application builder : 2007-8-11 14:36:41
// Target : M16
// Crystal: 16.000Mhz

#include <iom16v.h>
#include <macros.h>
#include <delay.h>

///////////////////////硬件接口/////////////////
#define DDR         DDRA
#define PORT        PORTA
#define PIN         PINA
///////////////////控制////////////////////////
#define CS_525      0
#define DIN_525     1
#define SCLK_525    2
#define	SETBIT(x,y) (x|=(1<<y))      //set bit y in byte x
#define	CLRBIT(x,y) (x&=(~(1<<y)))   //clear bit y in byte x
#define	CHKBIT(x,y) (x&(1<<y))       //check bit y in byte x
/////////////////////////////////////////////// 
#define Reg_Unchanged    0x0D
#define Reg_Updated      0X0f
#define Start_Up_Reg     0x04
#define Start_Up_Load    0x08
#define Shutdown         0x0c
//#define Mode_1           0x0e
//#define Mode_2           0x0a
//////////////////////////////////////////////

void Sent_to_max525(unsigned char Addr,int Data)
{
 unsigned char i,j;//temp;
 CLRBIT(PORT,CS_525);     //CS=0
 
 //CLRBIT(PORT,SCLK_525);
 //SETBIT(PORT,SCLK_525);
 ////////////////////////////////////////////////
 for (i=0;i<4;i++)      //传地址4位
 {
   	
  CLRBIT(PORT,SCLK_525);
  
  if(Addr&0x08)
    SETBIT(PORT,DIN_525);
  else
    CLRBIT(PORT,DIN_525);
  
  	
  SETBIT(PORT,SCLK_525);
  //CLRBIT(PORT,SCLK_525);
   Addr=Addr<<1;
 }
/////////////////////////////////////////////////////
  for (j=0;j<12;j++)      //传数据12位
 {
  
  CLRBIT(PORT,SCLK_525);
  
  if(Data&0x0800)
    SETBIT(PORT,DIN_525);
  else
    CLRBIT(PORT,DIN_525);
   
  SETBIT(PORT,SCLK_525);
  Data=Data<<1;
 }
  
  SETBIT(PORT,SCLK_525);
  delay_nus(50);
  CLRBIT(PORT,SCLK_525);
  SETBIT(PORT,CS_525);     //CS=1
}

///////////////////////////////////////////////////////
void port_init(void)
{
 PORTA = 0xff;
 DDRA  = 0xff;
 PORTB = 0xff;
 DDRB  = 0xff;
 PORTC = 0x00; //m103 output only
 DDRC  = 0x00;
 PORTD = 0x00;
 DDRD  = 0x00;
}

//call this routine to initialize all peripherals
void init_devices(void)
{
 //stop errant interrupts until set up
 CLI(); //disable all interrupts
 port_init();

 MCUCR = 0x00;
 GICR  = 0x00;
 TIMSK = 0x00; //timer interrupt sources
 SEI(); //re-enable interrupts
 //all peripherals are now initialized
}

void main()
{
// unsigned char i,Addr=0xaA;
 init_devices();
 //CLI();
   Sent_to_max525(0x04,0x000);
while(1)
 {
  //Sent_to_max525(0x08,0x0);

  
  Sent_to_max525(0x0f,0xfff);
  Sent_to_max525(0x0f,0x000);
  // Sent_to_max525(0x0f,0xfff);
   //Sent_to_max525(0x0f,0xfff);
 // Sent_to_max525(0x0f,0xFFF);
  //(0x0f,0x0FFF);
  //delay_nms(100);
  //Sent_to_max525(0x0f,0x0000);
 } 
 
}