ROM-Reader for Super Nintendo / Super Famicom Game Cartridges

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Found a small checksum error bug in the compare_checksum(). Similar to the earlier checksum error bug in getCartInfo(). Need to make sure we compare 4 characters. The original sprintf code used "%X" which drops leading 0s resulting in an error.

void compare_checksum() {
...
  char calcsumStr[5];
  sprintf(calcsumStr, "%04X", calc_checksum(fileName, folder));
...
}

I discovered the bug dumping Super Power League 4 because it has checksum 0x01AA. I can now confirm that my SPC7110 code changes work with all 3 carts - FEOEZ, MDH, and SPL4.

The checksum verification code need to be tweaked for MDH - the checksum should be checksum*2. EDIT: Here's the calc_checksum code addition:

unsigned int calc_checksum (char* fileName, char* folder) {
...
    else if (calcFilesize == 24 || calcFilesize == 28) {
      // Momotarou Dentestu Happy Fix 3MB (24Mbit)
      if ((calcFilesize == 24) && (romSizeExp = 0x0C)) {
       for (unsigned long i = 0; i < myFile.fileSize(); i++) {
          calcChecksum += myFile.read();
       }
       calcChecksum = 2 * calcChecksum;
      }
      else {
        for (unsigned long i = 0; i < (calcFilesize / 16); i++ ) {
          // Add all the bits in the 16Mbit chunks
          for (unsigned long j = 0; j < 2097152; j++) {
            calcChecksum += myFile.read();
          }
          // Add all the chunks together
          calcChecksum +=  calcChecksumChunk;
          calcChecksumChunk = 0;
        }
        // Add the 8Mbit rest
        for (unsigned long j = 0; j < 1048576; j++) {
          calcChecksumChunk += myFile.read();
        }
        calcChecksum +=  2 * calcChecksumChunk;
      }
    }
...
}