Couldnt really find a section for this..

[88GreenVN]

"but remember, these are hexadecimal" - not "then convert them to hexadecimal"

Ok that still is not working ie I get

( ( 14+88+56 ) ^FF ) = 0D F2 = 4F 0B

4F0B D728 EE11 956A

[festy]

4FB0?

[88GreenVN]

OK got some programming done and found that I can get upto 700,070kms to write. I also tried 999,997 kms but it failed to write to the chip. All others readings under 700,070 have worked no problem.

[88GreenVN]

And now I know a trip computer will roll over to start back at zero

Myth busted - it wont stop at 999,999 kms.

[vn5000]

Sweet .So if youve got enough time then you can use a pulse generator.I wonder what the max frequency or km/h the dash can handle.
Also once you got the programming sorted did you try programming the ic on the board soldered in place.

[festy]

I hope it could take a very fast pulse... to knock 100,000 km off your odo with a 40Hz pulse would take just on a year

[vn5000]

Yeah.Or 150 days at 250km/h.

[88GreenVN]

Also once you got the programming sorted did you try programming the ic on the board soldered in place.

No have to take the ic off. Now I'm fixing the spreadsheet error for the larger number groups that fail.

[88GreenVN]

Well after a few dasys with nose in the study books (and some valuable assistance from site members) I have fixed the spread sheet calcs and have the process worked out.

Now to fix all the broken readings I smashed up while not knowing what I needed to do

[88GreenVN]

As testing progressed on the trip computer I noticed that in Diagnostic mode the trip computer shows "FAIL" in the middle screen. The diag mode has 3 modes to scroll through, the last showing all segments in the LCD screens.

Looking over the BIN files in Ponyprog the first 8 bits look all over the shop in most files (The ODO has the correct kms showing.)

However a the BIN file recorded like 358604 still works properly - even when written to a replacement x2444.
first 8 bits
358604 = 01 01 D9 26 FF 00 DF 20 - (WORKS) FD 02 53 AC 9E 61 DF 20
101308 = 00 8A 00 00 08 00 08 08 (FAILS) D4 2B F7 08 37 C8 EF 10

I think I missed the bit on how to structure the first 8 bits of data!