xtest17_3.c

AT91sam7s 256 B/D example

/* ========================================================================== */
/*	    Xtest17_3.c : A/D Conversion of AD4(LM35DZ) and AD5(VR1)	      */
/* ========================================================================== */
/*			  Designed and programmed by Duck-Yong Yoon in 2007.  */

#include "AT91SAM7S256.h"
#include "lib_AT91SAM7S256.h"
#include "OK7S256ads.h"

void LCD_2d1(float number)			/* floating-point number xx.x */
{ unsigned int i, j;

  j = (int)(number*10. + 0.5);
  i = j / 100;					// 10^1
  if(i == 0) LCD_data(' ');
  else       LCD_data(i + '0');

  j = j % 100;					// 10^0
  i = j / 10;
  LCD_data(i + '0');
  LCD_data('.');

  i = j % 10;					// 10^-1
  LCD_data(i + '0');
}

void LCD_1d2(float number)		        /* floating-point number x.xx */
{ unsigned int i, j;

  j = (int)(number*100. + 0.5);
  i = j / 100;					// 10^0
  LCD_data(i + '0');
  LCD_data('.');

  j = j % 100;					// 10^-1
  i = j / 10;
  LCD_data(i + '0');

  i = j % 10;					// 10^-2
  LCD_data(i + '0');
}

int main(void)
{ unsigned int i, sum;

  MCU_initialize();				// initialize AT91SAM7S256 & kit
  Delay_ms(50);					// wait for system stabilization
  LCD_initialize();				// initialize text LCD module

  LCD_string(0x80,"LM35 = 00.0 [");		// display title
  LCD_data(0xDF);
  LCD_string(0x8E,"C]");
  LCD_string(0xC0," VR1 = 0.00 [V] ");
  Beep();

  AT91F_ADC_CfgPMC();				// enable peripheral clock for ADC
  AT91F_ADC_SoftReset(AT91C_BASE_ADC);		// clear all previous ADC settings
  *AT91C_ADC_MR = 0x02020400;			// SHTIM=2 (sample & hold time = 625ns)
						// STARTUP=2 (startup time = 5us)
						// 4.8MHz, 10 bit, software trigger

  while(1)
    { AT91F_ADC_DisableChannel(AT91C_BASE_ADC, AT91C_ADC_CH5);
      AT91F_ADC_EnableChannel(AT91C_BASE_ADC, AT91C_ADC_CH4); // select CH4 for LM35DZ
      sum = 0;
      for(i=0; i<32; i++)
        { AT91F_ADC_StartConversion(AT91C_BASE_ADC); // start conversion
          while(!(AT91F_ADC_GetStatus(AT91C_BASE_ADC) & AT91C_ADC_EOC4)); // wait for EOC
          sum += AT91F_ADC_GetConvertedDataCH4(AT91C_BASE_ADC); // add A/D result 32 times
          Delay_ms(1);
        }
      sum >>= 5;				// divide sum by 32 for average value
      LCD_command(0x87);                        // display temperature(xx.x)
      LCD_2d1((float)sum * 66. / 1024.);	// temperature = sum*66/1024

      AT91F_ADC_DisableChannel(AT91C_BASE_ADC, AT91C_ADC_CH4);
      AT91F_ADC_EnableChannel(AT91C_BASE_ADC, AT91C_ADC_CH5); // select CH5 for VR1
      sum = 0;
      for(i=0; i<32; i++)
        { AT91F_ADC_StartConversion(AT91C_BASE_ADC); // start conversion
          while(!(AT91F_ADC_GetStatus(AT91C_BASE_ADC) & AT91C_ADC_EOC5)); // wait for EOC
          sum += AT91F_ADC_GetConvertedDataCH5(AT91C_BASE_ADC); // add A/D result 32 times
          Delay_ms(1);
        }
      sum >>= 5;				// divide sum by 32 for average value
      LCD_command(0xC7);                        // display voltage(x.xx)
      LCD_1d2((float)sum*3.3/1024.);		// voltage = sum*3.3/1024

      Delay_ms(250);                            // delay 250 ms
    }
}