flasherase.c

CHP 2 - Real-Time Digital Signal Processing: Implementations and Applications, Second Edition by Sen

// 
//  Project: Experiment 2.10.5 Flash Programming - Chapter 2 
//  File name: flashErase.c   
//  Function: flashErase()        
//
//  Description: This function erase the entire C5510 DSK flash memory 
//               Note: this funciton is for AMD: AM29LV400B
//
//  For the book "Real Time Digital Signal Processing: 
//                Implementation and Application, 2nd Ed"
//                By Sen M. Kuo, Bob H. Lee, and Wenshun Tian
//                Publisher: John Wiley and Sons, Ltd
//
//  Tools used: CCS v.2.12.07
//              TMS320VC5510 DSK Rev-C
//

#include "flash.h"

#pragma CODE_SECTION(flashErase, ".text:example:flashErase");

short flashErase()
{           
  volatile unsigned long *fBase;
  short retValue;
  volatile short i;
        
  // Issue flash chip erase sequence: AA-55-80-AA-55-10
  *((volatile unsigned short *)FLASH_MEM_ADDR555) = FLASH_MEM_AA;
  *((volatile unsigned short *)FLASH_MEM_ADDR2AA) = FLASH_MEM_55;
  *((volatile unsigned short *)FLASH_MEM_ADDR555) = FLASH_MEM_SETUP;  
  *((volatile unsigned short *)FLASH_MEM_ADDR555) = FLASH_MEM_AA;
  *((volatile unsigned short *)FLASH_MEM_ADDR2AA) = FLASH_MEM_55;
  *((volatile unsigned short *)FLASH_MEM_ADDR555) = FLASH_MEM_ERASE;  
    
  // Wait until flash erase complete
  fBase = (unsigned long *)(FLASH_MEM_BASE);
  for (i=0; i<1000; i++) ;
  while(1) 
  {
    if ((*fBase & FLASH_MEM_DQ7) == FLASH_MEM_DQ7)   
    {
      retValue = 0;      // Normal return
      break;
    }         
    else if ((*fBase & FLASH_MEM_DQ5) == FLASH_MEM_DQ5)   
    {  
      if ((*fBase & FLASH_MEM_DQ7) != FLASH_MEM_DQ7)     
      {
        retValue = 1;    // Erase failed and timed out
        break;
      }
    }  
  }   
  flashReset();
  return (retValue); 
}