tms470r1a256_adc10_02.c

tmp470开发板的源程序

//******************************************************************************
//  Functional
//  TMS470 Demo - MibADC Sample ADIN0 Continuous 20KSPS
//
//  Description; A single sample is made continously ADIN0 with reference to
//  AVcc/AVss. Software toggles HET31 after each conversion
//  Software sets starts sample and conversion and polls for end of conversion.
//
//  Total sample and convert time = 12MHz/(8*((62+2)+11)) = 20KSPS
//  ACLK = SYSCLK = MCLK = ICLK = 12MHz
//  //*An external 12Mhz XTAL on OSCIN OSCOUT with proper load caps required*//	
//
//              TMS-FET470A256
//             -----------------
//         /|\|            OSCIN|-
//          | |                 | 12MHz
//          --|PLLDIS     OSCOUT|-
//            |                 |
//        >---|ADIN0       HET31|---> Toggle
//            |                 |
//
//  M.Buccini/J.Mangino
//  Texas Instruments, Inc
//  December 2004
//  Built with IAR Embedded Workbench Version: 3.20A
//******************************************************************************

#include <intrinsic.h>
#include "iotms470r1a256.h"
#include "tms470r1a256_bit_definitions.h"

void main(void)
{
  PCR = CLKDIV_1;                         // ICLK = SYSCLK
  PCR |= PENABLE;                         // enable peripherals

  HETDIR  = 0xFFFFFFFF;                   // HETx Output direction
  HETDOUT = 0xFFFFFFFF;

  ADCR1 |= PS_8;                          // ADCLK prescaler = 8
  ADSAMPEV |= SEN;                        // ADCSAMP1 controls SW
  ADSAMP1 = 62;                           // SW = 62+2
  ADCR1 |= ADC_EN;                        // Enable ADC
  ADISR1 = 0x0001;                        // Convert croup 1 = channel 0
  ADCR2 |= G1_MODE;                       // Continuous Conversion

  for (;;)
  {
    while (!(ADSR & GP1_END));            // Wait for conversion to complete
    HETDOUT ^= 0x80000000;                // Toggle
    ADSR |= GP1_END;                      // Clears flag
  }
}