PCM Hammer P12 development

[Gampy]

Yup, I just sent a test without them, but we do need to see if we can find tidbits like that to verify files ... I'm sure in time we'll learn more.

[Tazzi]

Well, AA55 does appear in the bin at FFFF8 along with FFFF at that location.. soooo. maybe thats all it checks?

Id assume thats a "sanity check" to ensure its not all FF's or 00's. Then a checksum check ontop would verify its not corrupted.

[antus]

Yeah I would include that check at this point for those 4 bytes. Its not going to hurt, and might help.

[Gampy]

I just used AA 55 ... Have tests out, will test this next round.

[antus]

Id assume thats a "sanity check" to ensure its not all FF's or 00's. Then a checksum check ontop would verify its not corrupted.

Yeah thats a good hardware test actually, AA55 would confirm all bits are toggling and in the right order so that would check that no address or data lines are stuck, and the flash is programmed. not foolproof, but reasonably sound for the simplicity. And only about 30 bytes of program space, and bugger all runtime.

[Gampy]

The Signature detection is limited to AA55 starting at 0xFFFF8, hopefully time/understanding will prove up more.
If it should be expand to include the following FFFF, or whatever else please do so speak your mind!
Tazzi, I wasn't sure what you were meaning when you mentioned them ... They are also part of the Signature ??

File Checksum validation has been skipped, I have barely looked at the file yet, I do not know the file layout, let alone how to do the checksums for it.
Besides I don't do checksums ... It's math! I'll leave that to those that are smarter then I.

If someone has found the OsID somewhere other then at 0x800C, and hopefully in hex, I'd would appreciate that info.
It's ASCII Text at that location ... It's a bit more difficult to extract then integer values.

Test is out, we'll see if I've butchered it up enough ...

[kur4o]

Os is at 8004 in hex.

Checksum are much more like e38-on type. You have a crc-16 and than a sum that also include the crc-16 one. SO it must be done in particular order.
Ranges can be taken from bin, read at specific address. Not a big deal but you need to add necessary changes to pcmhammer. There is also a boot block checksum 0-4000.

[Gampy]

Thank you!

That's scary, don't know how I missed that ...

I did look at what you did in xml for UP, couldn't decipher it, I moved on ...

[kur4o]

It is some scripting, no wonder there is no hints.
If you have
@8022*3 means read 3 start-end ranges at address 8022
#4 means 04 bytes from start of segment.

[Gampy]

Sorry, I must be dense, still to cryptic for me ...