Help with Checksum

kirkm · Post by **kirkm** » Sun Jul 22, 2007 6:15 am

I am new to PCM programming and having problems changing a bin file using Tunerpro 4.14.033. The bin image is from a 1995 LT1 Corvette automatic (original stock) using a EE.xdf definition from the Moates site. Scanning through the values in Tunerpro I see values I would expect. If I save the file without making any changes (SaveAs) , it saves fine but the checksum is invalid using the tunercat checksum checker? The original bin checksum validates with no error. Is this a bug or am I doing something wrong?

Kirk

Post by **Mangus** » Sun Jul 22, 2007 9:25 am

Hi Kirk -

I believe the checkums are calculated incorrectly in the EE definitions on the Moates site. I've been looking to fix them. I'll try to do so this week.

In the meantime, you can disable the checksum by changing the mask ID byte (EE) to 0xAA.

-Mark

kirkm · Post by **kirkm** » Sun Jul 22, 2007 10:44 am

Mark,

Thanks for the quick response.

One thing I did not mention is that I flashed my computer with the image not knowing the checksum was bad. I could no longer communicate to the computer after the flash and get a rapid flashing check check engine light. I assume the computer is toast until the flash chip replaced? Is this true? The good news is it is a spare computer and still have the original intact.

Kirk

Post by **Mangus** » Sun Jul 22, 2007 1:44 pm

That's a good question. Come to think of it, you might be right - if you can't get an ALDL link, it's not possible to flash the PCM over ALDL.

Post by **Mangus** » Sun Jul 22, 2007 1:58 pm

OK, I've fixed the checksums on the moates.net definitions. They were off-by-one (end should have been FFFF and 1FFFF).

kirkm · Post by **kirkm** » Mon Jul 23, 2007 2:51 pm

That did the trick. Thanks!

Is there a stream definition available for $ee (1995 Corvette A4) available? I have downloaded and tried one for an 1994 F Car and get error after a second or two of monitoring. I think it is A223 and/or A275 looking at other tools. What is the relationship of the DS files in the ALDLstuff.zip to ADS files?

Thanks,

Kirk

Post by **Mangus** » Mon Jul 23, 2007 3:38 pm

TunerPro has some issues connecting to 94/95 LT1s, but ScannerPro does not. ScannerPro will be integrated into TunerPro v5.

www.scannerpro.net