main.c

这是单片机C51典型应用设计代码

#include <ADUC831.H>
#include <stdio.h>

void main (void)
{
unsigned char chan_2_convert;

/*-----------------------------------------------
Configure the serial port to run at 9600 Baud.
-----------------------------------------------*/
  SCON  = 0x50;               // SCON: mode 1, 8-bit UART, enable rcvr
  TMOD  = 0x20;               // TMOD: timer 1, mode 2, 8-bit reload
  TH1   = 0xFD;               // TH1:  reload value for 9600 baud @ 11MHz
  PCON &= 0x7F;				        // SMOD: Reset SMOD bit in PCON disables UART baud rate doubler
  TR1   = 1;                  // TR1:  timer 1 run
  TI    = 1;                  // TI:   set TI to send first char of UART
  EA    = 1;				  

/*-----------------------------------------------
Configure the A/D to sequentially convert each
input channel.
-----------------------------------------------*/
ADCCON1 = 0xFC;     // 1111 1100

while (1)
  {
  unsigned int conv_val;
  unsigned char channel;

/*-----------------------------------------------
Start a conversion and wait for it to complete.
-----------------------------------------------*/
  chan_2_convert = (chan_2_convert + 1) % 8;
  ADCCON2 = (ADCCON2 & 0xF0) | chan_2_convert;
  SCONV = 1;
  while (ADCCON3 & 0x80);

/*-----------------------------------------------
Read A/D data and print it out.
-----------------------------------------------*/
  channel  = ADCDATAH >> 4;
  conv_val = ADCDATAL | ((ADCDATAH & 0x0F) << 8);

  printf ("ADC Channel %bu = 0x%4.4X\r\n", channel, conv_val);
  }

}