// filename  adtest.C  

// Test of 6812 8-bit ADC

// 1 Hz sampling and output to  serial port

// Last modified 12/12/02 by Jonathan W. Valvano

 

// Copyright 2003 by Jonathan W. Valvano, valvano@uts.cc.utexas.edu 

//    You may use, edit, run or distribute this file 

//    as long as the above copyright notice remains 



#include "HC12.h"

#include "SCI12.H"



void CycleWait(unsigned int delay){ int Endt;

  Endt = TCNT+delay;          /* Time (125ns cycles) to wait */

  while((Endt-(int)TCNT)>0);  /* wait */

}

//******** SecWait *************** 

// wait 1 second, using TCNT

void SecWait(unsigned int sec){ unsigned int i,j;

  for(i=0; i<sec; i++){

    for(j=0; j<1000; j++){

      CycleWait(8000);   // 1ms wait

    }

  }

}

//******** ADC_Sample *************** 

// perform 4 ADC samples on Chan

// return sum of 4 sample

unsigned short ADC_Sample(unsigned short chan){ 

  ATDCTL5 = chan;                 // start sequence

  while((ATDSTAT&0x8000)==0){};   // wait for SCF

  return ADR0H+ADR1H+ADR2H+ADR3H; 

}

    

//******** ShowSample *************** 

// perform 4 ADC samples on Chan

// print Chan and 4 results on serial port

// wait 1 second

void ShowSample(unsigned short chan){ unsigned short result;

  PORTT ^= 0x40;   // toggle LED

  SCI_OutUDec(chan);

  SCI_OutString(" = ");

  result = ADC_Sample(chan);         // 0 to 1020

  SCI_OutUDec(result);  SCI_OutChar(CR);

  SecWait(1);  // sampling rate is about 1Hz

}



//******** ADC_Init *************** 

// Initialize ADC 

void ADC_Init(void){

  ATDCTL2 = 0x80; // enable ADC

}

void main(void){ int i;

  unsigned int channel;

  COPCTL = 0x00;  // disable COP 

  DDRT |= 0x40;   // PortT bit 6 is output to LED

  TSCR = 0x80;    // TEN(enable) 8 MHz

  ADC_Init();     // initialize ADC, COP, Port T 

  SCI_Init(13);

  SCI_OutString("Adapt812 ADC test 12/12/02 -JWV"); SCI_OutChar(CR);

  SCI_OutString("Chan sum of 4 samples"); SCI_OutChar(CR);

  while(1){

    for(channel=0; channel<=7; channel++) {

      ShowSample(channel);

    }

    for(channel=12; channel<=14; channel++) {

       ShowSample(channel);

    }

  }

}



#include "SCI12.C"

extern void _start();	

#pragma abs_address:0xfffe

void (*reset_vector[])() = { _start };

#pragma end_abs_address