het_pwm_01.c

tmp470开发板的源程序

//******************************************************************************
//  TMS470 Demo - HET used to generate PWM
//
//  Program name : HET_PWM_01.c associated with HET program HET_PWM_01_H.het
//
//  This programs initializes the HET using the ECMP instruction to
//  generate two PWMs of 25% and 50% duty cycle. The pulses is generated by the
//  HET on CC0 and CC2 lighting the corresponding LEDs.
//
//  *An external 12Mhz XTAL on OSCIN OSCOUT with proper load caps required*
//
//              TMS-FET470A256
//             -----------------
//         /|\|            OSCIN|-
//          | |                 | 12MHz
//          --|PLLDIS     OSCOUT|-
//            |                 |
//            |            CC0  |---> LED
//            |                 |
//            |            CC2  |---> LED
//            |                 |
//
//  John Mangino / Andreas Dannenberg
//  Texas Instruments, Inc
//  May 2005
//  Built with IAR Embedded Workbench Version: 4.20A
//  A256 EVM
//******************************************************************************
#include <intrinsic.h>
#include "iotms470r1a256.h"
#include "tms470r1a256_bit_definitions.h"
#include "std_het.h"
#include "HET_PWM_01_H.h"

__no_init volatile HETPROGRAM0_UN e_HETPROGRAM0_UN @ 0x00800000;

void MemCopy32(unsigned long *dst, unsigned long *src, int bytes)
{
  for (int i = 0; i < (bytes + 3) / 4; i++)
    *dst++ = *src++;
}

void main(void)
{
  // Set up peripheral registers.
  // First disable interrupts.
  __disable_interrupt();

  PCR = CLKDIV_1;                        // ICLK = SYSCLK/4
  PCR |= PENABLE;                        // enable peripherals

  HETGCR = CLK_MASTER + IGNORE_SUSPEND;  //  HET Master Mode, Ignore SW BP

  // copy HET instructions to HET ram

  MemCopy32((void *) &e_HETPROGRAM0_UN, (void *) HET_INIT0_PST,
            sizeof(HET_INIT0_PST));

  HETPFR = 0x0000052b;                   // Set PFR register	

  HETDIR  = 0xFFFFFFFF;                  // Set all HET as GIO outputs
  HETDOUT = 0xFFFFFFFF;                  // Flash all leds off and on and off

  HETGCR |= ON;                          // Start HET

  __enable_interrupt();                  // Enable Interrupts

  while(1);
}