hi everyone.
i have Ecu AC Delco E84 for spark M400 and some file calib of this. now i need modify some byte on calib file but i can't not realize what is algorithm checksum of this file.
please help me find checksum fomular. thank you very much.
i have 3 file with 1 purpose 25202848, 25202950, 25202953. after i compare 3 file, i realize $08 -> $0b is length of this file - 12 byte, $0d-$0e maybe a checksum, $12-$15 is a name of file, and $28-$29 is CVN.
but i can't find how it calculate to check sum ( i tried not (sum 16 bit big ediant ) +1, or sometihing like this) but not success. i just want to change name of this calib file to name i want. please help me find it out. thank you very much.
Need to find AC DelCo E84 ECM Calib file checksum algorithm
Need to find AC DelCo E84 ECM Calib file checksum algorithm
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- ecu - 04 calib.zip
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Re: Need to find AC DelCo E84 ECM Calib file checksum algori
Do you have more files for that pcm I will look for more patterns. Also a full dump from pcm will help too.
The files you have are compressed, for that reason you can`t get find a good checksum algo.
After the file is decompressed it uses standard checksum routine that is known already.
The files you have are compressed, for that reason you can`t get find a good checksum algo.
After the file is decompressed it uses standard checksum routine that is known already.
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Re: Need to find AC DelCo E84 ECM Calib file checksum algori
Ill pm you a full file.
Re: Need to find AC DelCo E84 ECM Calib file checksum algori
What do you want to do
I didn't understand anything again
I can work with files of this format
I didn't understand anything again
I can work with files of this format
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- Posts: 1
- Joined: Thu Jul 22, 2021 11:15 pm
Re: Need to find AC DelCo E84 ECM Calib file checksum algori
try crc16 poly 8005. sometimes called crc16 buypass