Here's an example of a modified file:

File 'c:\d_drive\bins\unknown\abul.bin'
Address: 0xd000,0xdfff
CRC: 0xbbf73d49
Mask ID: 42
ID byte: 0x42
Sum word: 0x8969 (should be 0x8f39)
Scan ID: 7941
BCC: BDR4376
BCC: ABUL8235

The checksum does not match OEM which means this is a modified chip. Who knows what's changed, so I probably won't use this for anything but educational purposes.