Mefi5 tuner pro xdf and checksum calculations bin files

[04colyZQ8]

Looking for help on this mefi5 bin file I think it is mefi5B its 16kb first 4 bytes are the checksum cannot for the life of me calculate it? I have a xdf for a mefi5a but that doesn't work on my controller or calculate the checksums, if anyone has xdfs to share or at least tell me the start and ending file lengths as specified in tuner pro for the checksum calculation! Looking for others who have mefi bins and xdfs.

I have tired for two years to get a hold of Bob from mefi burn! He will not answer my calls! I guess he is out of business? Because I would like to buy stuff from him!! and my cable is not working well loose connection at the box to obd2 adapter, was hoping he might sell me a new box or plug to solder on.

Here is me mefi5b please help calculating the checksum!
This is the mefi5a checksum:

mefi5achecksum.png (32.72 KiB) Viewed 1464 times

And the mefi5B cal file :

mefi5b.bin

(16 KiB) Downloaded 45 times

[antus]

It looks like its standard crc32 from 4-2FFF

Must be your and my lucky day, I saw the FFFFs around that offset and got it first guess!

[antus]

Tunerpro doesnt seem to have CRC out of the box, so you'll need a checksum plugin that provides it, or another tool that can fix it outside of tuner pro. At a minimum you can use hxd like I have above and then type the sum over the first 4 bytes. Just be careful to overwrite, not insert and change all the offsets and extend the file size, obvious problems there.

[04colyZQ8]

Ok great I kept trying around those ffffs as well wondered what that extra stuff was on the end of the file! I tried 4-2fff8, 4-2fffc, 4-2fffa, 4-2fffb no dice must be the tuber pro plugin not working well. I do have an extra plugin for it.

[antus]

My copy of tunerpro (might be out of date) only has checksums and 1s or 2s compliment (which are still checksums), not CRC sums, so its just not capable of the new algorithm needed out of the box.

[04colyZQ8]

Tunerpro doesnt seem to have CRC out of the box, so you'll need a checksum plugin that provides it, or another tool that can fix it outside of tuner pro. At a minimum you can use hxd like I have above and then type the sum over the first 4 bytes. Just be careful to overwrite, not insert and change all the offsets and extend the file size, obvious problems there.

Done that before .. usually results in bricking it!

[antus]

yep, figuring this stuff out is dangerous. Ideally you want an editor that'll make a change and update the sums. Then you can do the same change manually and see if you get the same end result, or if there is a second sum you have missed.