adc1.c

基于c8051f320单片机开发的实验例程

/*****************************************************************************
功能:实现ADC采样芯片外的模拟电压，通过LCD显示，并通过串口发送到PC机
     实验时短接以下跳线：J7.1--J7.2；J9.1--J9.2
     
版本:V1.0
*****************************************************************************/
#include <c8051f320.h>                 // SFR declarations
#include <stdio.h>
#include <INTRINS.H>
//-----------------------------------------------------------------------------
// 16-bit SFR Definitions for 'F02x
//-----------------------------------------------------------------------------
sfr16 DP       = 0x82;                 // data pointer
sfr16 TMR2RL   = 0xca;                 // Timer2 reload value
sfr16 TMR2     = 0xcc;                 // Timer2 counter
sfr16 TMR3RL   = 0x92;                 // Timer3 reload value
sfr16 TMR3     = 0x94;                 // Timer3 counter
sfr16 ADC0     = 0xbd;                 // ADC0 data
sfr16 ADC0GT   = 0xc4;                 // ADC0 greater than window
sfr16 ADC0LT   = 0xc6;                 // ADC0 less than window
sfr16 RCAP2    = 0xca;                 // Timer2 capture/reload
sfr16 T2       = 0xcc;                 // Timer2

#define BAUDRATE     38400              // Baud rate of UART in bps
#define SYSCLK       12000000          // SYSCLK frequency in Hz     
#define SAMPLE_RATE  50000             // Sample frequency in Hz
#define INT_DEC      256               // integrate and decimate ratio

void PORT_Init (void);
void UART0_Init (void);
void ADC0_Init (void);
void Timer2_Init (int counts);
void ADC0_ISR (void);
void Write_CHAR(unsigned char yjchar);
void Write_COM(unsigned char yjcom );
void YJ_Init(void);
void SPI0_Init (void);

long result;
unsigned char NCDdata[10]={0x30};
//------------------------------------------------------------------------------
//main
//------------------------------------------------------------------------------
void main (void) {
   int temp_int, temp_frac,i;            // integer and fractional portions of
   unsigned int temperature;
   long  x;
                                         // Disable Watchdog timer
   PCA0MD &= ~0x40;                      // WDTE = 0 (clear watchdog timer 
                                         // enable)
   OSCICN |= 0x03;                       // Set internal oscillator to highest

   PORT_Init ();                         // initialize crossbar and GPIO
  
   
   SPI0_Init ();

   Timer2_Init (SYSCLK/SAMPLE_RATE);     // initialize Timer3 to overflow at
                                         // sample rate
   UART0_Init ();                        // initialize UART0
   
   ADC0_Init ();                         // init ADC

   AD0EN = 1;                            // enable ADC
   
   EA = 1; 
      
   while(result==0);				     //等于0,侧等待                     
   while (1) {
     EA = 0;                             // 关中断
     temperature = result;
	 temperature &=0x000fff;
     EA = 1;                             //开中断
     temperature = temperature*100L*3/1024;
     temp_int  = temperature/100;
	 temp_frac = temperature - (temp_int * 100);
     for(x=0;x<400;x++);
	
     for(x=0;x<400;x++);

     printf ("V_input is %02d.%02dV\n", temp_int, temp_frac);
	 
	 YJ_Init();
	 NCDdata[0]=temp_int/100+0x30;NCDdata[1]=(temp_int%100)/10+0x30;NCDdata[2]=(temp_int%100)%10+0x30;NCDdata[3]=0x2e;
	 NCDdata[4]=temp_frac/10+0x30;NCDdata[5]=temp_frac%10+0x30;NCDdata[6]=0x20;NCDdata[7]=0x20;NCDdata[8]=0x20;
	 NCDdata[9]=0x20;NCDdata[10]=0x20;NCDdata[11]=0x20;NCDdata[12]=0x20;NCDdata[13]=0x20;NCDdata[14]=0x20;
     YJ_Init();
	 for(i=0;i<7;i++)
	  {
         Write_CHAR(NCDdata[i]);}	 
	}

}
//-----------------------------------------------------------------------------
// PORT配置
//-----------------------------------------------------------------------------
void PORT_Init (void)
{   
   P0SKIP    = 0x4E;
   XBR0    = 0x03;                     // Enable UART on P0.4(TX) and P0.5(RX)                     
   XBR1    = 0x40;                     // Enable crossbar and weak pull-ups
   P2MDIN    = 0x7f;                   // P2.7配置为模拟输入
//   P1SKIP    = 0x02;
   P0MDOUT |= 0xff;                    // enable TX0 as a push-pull output  
   P1MDOUT |= 0xff;
   P2MDOUT |= 0xF7;
   P3MDOUT |= 0x04;                    // P3.3 push-pull output
 
}
//-----------------------------------------------------------------------------
// UART0配置
//-----------------------------------------------------------------------------
// Configure the UART0 using Timer1, for <baudrate> and 8-N-1.
void UART0_Init (void)
{
   SCON0 = 0x10;                       // SCON0: 8-bit variable bit rate
                                       //        level of STOP bit is ignored
                                       //        RX enabled
                                       //        clear RI0 and TI0 bits
   if (SYSCLK/BAUDRATE/2/256 < 1) {
      TH1 = -(SYSCLK/BAUDRATE/2);
      CKCON &= ~0x0B;                  // T1M = 1; SCA1:0 = xx
      CKCON |=  0x08;
   } else if (SYSCLK/BAUDRATE/2/256 < 4) {
      TH1 = -(SYSCLK/BAUDRATE/2/4);
      CKCON &= ~0x0B;                  // T1M = 0; SCA1:0 = 01                  
      CKCON |=  0x09;
   } else if (SYSCLK/BAUDRATE/2/256 < 12) {
      TH1 = -(SYSCLK/BAUDRATE/2/12);
      CKCON &= ~0x0B;                  // T1M = 0; SCA1:0 = 00
   } else {
      TH1 = -(SYSCLK/BAUDRATE/2/48);
      CKCON &= ~0x0B;                  // T1M = 0; SCA1:0 = 10
      CKCON |=  0x02;
   }



   TL1 = TH1;                          // init Timer1
   TMOD &= ~0xf0;                      // TMOD: timer 1 in 8-bit autoreload
   TMOD |=  0x20;                       
   TR1 = 1;                            // START Timer1
   TI0 = 1;                            // Indicate TX0 ready 
}
//-----------------------------------------------------------------------------
// ADC0配置，T3定时启动ADC
//-----------------------------------------------------------------------------
void ADC0_Init (void)
{
   ADC0CN = 0xc2;                      // ADC0 T3定时采样
   REF0CN = 0x0e;                      // 启用内部基准源
   AMX0P     = 0x0F;
   AMX0N     = 0x1F;                   //选择采样输入源GND作为负输入ADC工作在单端方式
   ADC0CF = 0x38;			
   EIE1 |= 0x08;                       // 启用 ADC 中断
}
//-----------------------------------------------------------------------------
// Timer2配置，T2定时启动ADC
//-----------------------------------------------------------------------------
void Timer2_Init (int counts)
{
   TMR2CN = 0x00;                      // STOP Timer2; Clear TF2H and TF2L;
                                       // disable low-byte interrupt; disable
                                       // split mode; select internal timebase
   CKCON |= 0x10;                      // Timer2 uses SYSCLK as its timebase

   TMR2RL  = -counts;                  // Init reload values
   TMR2    = TMR2RL;                   // Init Timer2 with reload value
   ET2 = 0;                            // disable Timer2 interrupts
   TR2 = 1;                            // start Timer2
}

//-----------------------------------------------------------------------------
// ADC0采样中断
//-----------------------------------------------------------------------------
void ADC0_ISR (void) interrupt 10
{
   static unsigned int_dec=INT_DEC;    
   static long accumulator=0L;                     
    ADC0CN &= ~0x20;				    // 清 ADC 中断标志位
    accumulator += ADC0;                // 累加ADC采样数据
    int_dec--;                          // 指针减1

    if (int_dec == 0)
	 {                                  // 累加完了吗？
      int_dec = INT_DEC;                // 指针复位
      result = accumulator>>8;
      accumulator = 0L;                  // 累加和变量清0
     }
}
//------------------------------------------------------------------------------
//END OF FILE