adc.bak

msc12０0是工程评估板ＭＣＵ的原代码四个差分输入

//********************************************************************
// File name: adc.c
//
// Copyright 2003 Texas Instruments Inc as an  unpublished work. 
//
// Version 1.0
//
// Compiler Version (Keil V2.38), (Raisonance V6.10.13)
//
// Module Description:
//  ADC Example Program
//
//********************************************************************
#include "legal.c"         //Texas Instruments, Inc. copyright and liability 
#include <REG1200.H>       // The header file with the MSC register definitions
#include <stdio.h>         // Standard I/O so we can use the printf function

extern signed long bipolar(void);
extern void autobaud(void);
#define LSB 298e-9
#ifndef XTAL 				// if no XTAL compiler variable defined use:
	#define XTAL 11059200 	// XTAL frequency 11.0592 MHz
#endif

Main(void) {
    char i,j;
    float result;
	
    PDCON = 0x75;          // Turn on the A/D
    ACLK = XTAL/1000000;   // ACLK freq. = XTAL Freq./(ACLK +1) = 0.9216 MHz
                           // 0.9216 Mhz/64 = 14,400 Hz
    DECIMATION = 1440;     // Data Rate = 14,400/1,440 = 10 Hz
    ADMUX = 0x88;          // AINP = AIN7, AINN = AIN6  
    ADCON0 = 0x30;         // Vref On, 2.5V, Buffer Off, PGA=1

	CKCON = 0x10;	// MSC1200 Timer1 div 4
	TCON = 0;		// MSC1200 Stop TR1
    autobaud();
    ADCON1 = 0x01;         // bipolar, auto, self calibration, offset, gain
    printf("ADC Test, ACLK=%d\n",ACLK);
    //wait for the calibration to take place
    for (i=0;i<3;i++){     // dump 3 conversions
        while(!(AIPOL&0x20)) {}
        j=ADRESL; 
    }
	
	j=1;
    while(1){
        while(!(AIPOL&0x20)) {} // Waiting for conversion
        result=bipolar();     // Save Results
        printf ("%10.8f\t", result*LSB);
        if (!(j++%5)) printf("\n");   // Print 2 lines each second
    }
}