da_040.c

c8051f040实验程序含CAN SMBUS IIC

#include "C8051f040.h"

#define uchar unsigned char
#define uint unsigned int
void da_init();
void port_init();
void os_init();

char bdata ad=0;
sbit df0=ad^0;
sbit df1=ad^1;
sbit df2=ad^2;
char bdata as=0;
sbit sc0=as^0;

/*************************************************************************
*
*主函数
*************************************************************************/
void main()
{   char sd,sd1;
    WDTCN = 0xDE;              // 关闭看门狗
	WDTCN = 0xAD;
    os_init();
	SFRPAGE   = ADC0_PAGE;
    REF0CN    = 0x03;		   //内部参考电压
	da_init();
	while(1)
	{

	  df0=1;
	  df1=1;
	  df2=1;
	  sc0=1;
	  sd=ad;
	  sd1=as;
	  SFRPAGE   = DAC0_PAGE;
	  DAC0L=0x66;                 //改变此处的值后，在DAC0输出端的电压会随着变化
	  DAC0H=0x06;
	  SFRPAGE   = DAC1_PAGE;
	  DAC1L=0x00;
	  DAC1H=0x0f;              //改变此处的值后，在DAC1输出端的电压会随着变化
	 }
}
/************************************************************************
*
*DAC初始化函数
*************************************************************************/
void da_init()
{
    SFRPAGE   = DAC0_PAGE;
    DAC0CN    = 0x80;
    SFRPAGE   = DAC1_PAGE;
	DAC1CN    = 0x80;
}

/***********************************************************************
*
*系统时钟初始化，选择外部晶振
************************************************************************/
void os_init()
{
    uint i ;
	SFRPAGE   = CONFIG_PAGE;
	OSCXCN    = 0x67;
    for (i = 0; i < 3000; i++);  // 等待晶振稳定加的延时
    while ((OSCXCN & 0x80) == 0);
    CLKSEL    = 0x01;

}