pic_adc.c

基于温度传感器LM35与PIC16F877A的应用程序

#include <pic.h> 
#define portbit(address,bits) ((unsigned)(&address)*8 + (bits)) 
#define BUSY 0x80 
#define WRITE_DATA 0xff 
#define delay_data 0xff 
#define COMMAND 0x00 
#define LCD_CLEAR 0x01 
#define portdata PORTB 

volatile bit E  @ portbit(PORTD,7); 
volatile bit RW @ portbit(PORTD,6); 
volatile bit RS @ portbit(PORTD,5); 
bank2 volatile unsigned int temperature[40];
volatile unsigned int checksum;
volatile unsigned char count;
volatile double squ;

void delay(unsigned int delay_time) 
{ 
  unsigned char i;
  while (delay_time--)
  {
   for (i = 0; i <0xff; i ++)
    {
      } 
   }
}  

unsigned char lcd_busy(void) 
{ 
  unsigned char temp; 
   
  portdata = 0xff; 
  RS = 0; 
  RW = 1; 
  E = 1; 
  TRISB = 0xff; 
  temp = portdata; 
  TRISB = 0x00; 
  E = 0; 
  return (temp); 
} 

void lcd_command_writedata(unsigned char check,unsigned char data) 
{ 
  if (check == COMMAND) 
  { 
   RS = 0; 
   } 
  else 
  { 
   RS = 1; 
  } 
  RW = 0; 
  portdata = data; 
  E = 1; 
  E = 0; 
  while (lcd_busy() & BUSY); 
} 

void lcd_disp(unsigned char adr,unsigned char disp_data) 
{ 
 lcd_command_writedata(COMMAND,adr);
 lcd_command_writedata(WRITE_DATA,disp_data);
} 

void lcd_init(void) 
{ 
  lcd_command_writedata(COMMAND,LCD_CLEAR); 
  lcd_command_writedata(COMMAND,0x38); 
  lcd_command_writedata(COMMAND,0x0e); 
  lcd_command_writedata(COMMAND,0x06); 
} 

void system_init(void) 
{ 
  delay(10); 
  INTCON = 0x00; 
  OPTION = 0xff;
  TRISB = 0x00; 
  TRISD = 0x00; 
} 

void adc_init(void)
{
 ADCON1 = 0x8e;
 ADCON0 = 0x81;
 ADIF = 0;
 PEIE = 1;
 ADIE = 1;
 TRISA0 = 1;
 count = 0;
  }
 
void main(void) 
{ 
unsigned char i; 
unsigned long temperature_temp;
unsigned char a,b,c,d;

delay(delay_data); 
system_init(); 
lcd_init(); 
adc_init();
ADCON0 |= 0x04;
ei();
while (1) 
{ 
 while (1)
 {
  if (count == 40)
   {
     break;
     }
   }
  di();
  for (i = 0; i < 40; i ++)
   {
    checksum = checksum + temperature[i];
    }
  squ = (double)checksum;
  squ = squ / 4;
  temperature_temp = (unsigned long)((100 * squ) / 1023);
  a = temperature_temp / 100;
  lcd_disp(0x86, a + 0x30);
  d = temperature_temp % 100;
  b = d / 10;
  lcd_disp(0x87, b + 0x30);
  lcd_disp(0x88, 0x2e);
  c = temperature_temp - a * 100 - b * 10; 
  lcd_disp(0x89, c + 0x30);
  lcd_disp(0x8a, 0xdf);
  lcd_disp(0x8b, 0x43);
  checksum = 0;
  ADCON0 |= 0x04;
  count = 0;
  lcd_disp(0xcf, 0xfe);
  delay(1500);
  ei();
  } 
}

void interrupt adc_interrupt(void)
 {
  unsigned char i;
 
  ADIF = 0;
  temperature[count] = (ADRESH << 8) + ADRESL;
  count ++;
  i = 10;
  while(--i);
  ADCON0 |= 0x04;
   }