BlankCheck

int BlankCheck (
  unsigned long adr,          /* Block start address */
  unsigned long sz,           /* Block size in bytes */
  unsigned char pat);         /* Pattern to compare  */

The BlankCheck function can be used to check whether the specified block is empty, or whether the content is equal to a specific pattern pat.

The BlankCheck function returns the value:

• 0 - when the block content is equal to the pattern pat.
• 1 - when the block content differs from the pattern pat.

int BlankCheck (unsigned long adr, unsigned long sz, unsigned char pat) {

  unsigned long i, j, k;

  // Recalculate address for External SDRAM addresses
  if (adr >= SDRAM_START)
    adr = adr - SDRAM_START + USER_OFFSET;

  for (i = 0; i < sz; i += 256) {
    // Read 256 bytes
    ReadPage_HW (adr+i, 256, &rd_buf[0]);

    // Determine size to compare
    if ((sz-i) >= 256) k = 256;
    else               k = (sz-i);

    // Check up to 256 bytes if equal to pattern "pat"
    for (j = 0; j < k; j++)
      if (rd_buf[j] != pat) return (1); // Memory is not blank
  }

  return (0);                           // Memory is blank
}

Complete example exists in folder \KEIL\ARM\FLASH\AS352x_M25P40.