tms470r1a256_rti_01.c

tmp470开发板的源程序

//*******************************************************************************
//  TMS470 Demo - RTI Interrupts From TAP, CMP1 and CMP2
//
//  Description; Service TAP, CMP1 and CMP2 interrupts and toggle Pin HET0,
//  HET12 and HET31 in response. Software adds offset to CMP1 and CMP2 to
//  maintain intervals.
//  ACLK = SYSCLK = MCLK = ICLK = 12MHz
//  //*An external 12Mhz XTAL on OSCIN OSCOUT with proper load caps required*//	
//
//              TMS-FET470A256
//             -----------------
//         /|\|            OSCIN|-
//          | |                 | 12MHz
//          --|PLLDIS     OSCOUT|-
//            |                 |
//            |             HET0|---> LED Toggle
//            |            HET12|---> LED Toggle 2X
//            |            HET31|---> LED Toggle 4X
//            |                 |
//
//  M.Buccini/A.Dannenberg
//  Texas Instruments, Inc
//  January 2005
//  Built with IAR Embedded Workbench Version: 4.20A
//******************************************************************************

#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;

  RTIPCTL = 1;                            // Preload modulo /1
  RTICNTL |= TAPENA;                      // Enable TAP interrupt
  RTICMP1 = 1048576;
  RTICMP2 = 524288;
  RTICINT |= CMP1ENA + CMP2ENA;           // Enable CMP1/CMP2 interrupts
  REQMASK = (1 << CIM_TAP)+(1 << CIM_COMP1)+(1 << CIM_COMP2); // Enable RTI TAP/CMP1/2 chan's
  __enable_interrupt();                   // Enable interrupts

  for (;;) {}
}
//------------------------------------------------------------------------------
// TMS470R1A256 Standard Interrupt Handler
//------------------------------------------------------------------------------
#pragma vector = IRQV
__irq __arm void irq_handler(void)
{
   switch ((0xff & IRQIVEC) - 1)
  {
   case CIM_TAP:
    {
    RTICNTL &= ~ 0x80;                  // Clear TAP flag
    HETDOUT ^= 0x01;                    // Toggle using exclusive-OR
    break;
    }
   case CIM_COMP1:
    {
    RTICMP1 += 1048576;                 // Add offset
    RTICINT &= ~ 0x80;                  // Clear CMP1 flag
    HETDOUT ^= 0x1000;                  // Toggle using exclusive-OR
    break;
    }
   case CIM_COMP2:
    {
    RTICMP2 += 524288;                  // Add offset
    RTICINT &= ~ 0x40;                  // Clear CMP2 flag
    HETDOUT ^= 0x80000000;              // Toggle using exclusive-OR
    break;
    }
  }
}