RomRaider

Anybody know the difference between A8DK100X and A8DK101X for the USDM 07 WRX MT?
Mine came with a 100 and most of the open source Roms (gabedude and bullwinkle) branch off that.
I'd like to try Merp's SD rom, mostly for the LC and FFC features, but it only patches a 101X.

1. I'm assuming I could flash a 101 based ROM onto my 07 ECU with no issues
2. I'm just curious what Subaru might have changed. Can't find any reference to a TSB or anything, it was probably a running change of some sort.

The ROM compare tool says they're different but it doesn't identify it as table values that have changed.

Minor changes like this tend to be 'non-service updates', I.e. they're only applied to cars that come off the line. Yes it should still work as one is just a newer ROM for the same car than the other. It is likely that if the maps have not changed then some of the logic has.

It would be interesting to determine what they changed in the logic. Unfortunately I don't yet have the skills to reverse engineer the ROM otherwise I'd investigate myself.

The ECU ID's are compatible, flash in a 101X non-SD version to check car idles and drives fine before converting to SD

How do you compare ECU ID to determine which ROM can be used?

4D1258 sequence means the ECU firmware and hardware is identical. The final 4006 and 4106 means the 4106 was a minor revision possibly to address an issue Subaru found during warranty period

viewtopic.php?f=35&t=7591

2007 USDM Subaru Impreza WRX MT A8DK100X 4D12584006
2007 USDM Subaru Impreza WRX MT A8DK101X 4D12584106


I found the same thing when i was trying to define an A4SE50TI ROM, I found that the A4SE900I used the exact same ECU ID which made upgrading to a define ROM quite easy

Yep, these two roms are compatible. To avoid any complications and keep things moving quickly I have opted only to patch the latest rom for each model year/market/model.

I will add a note to the download page as this is the case for a couple different roms.

Thanks for the info on assuring compatibility.
I'm actually considering using it for its LC and FFC functionality, planning on leaving it in MAF mode. I don't have any modifications that warrant using SD.

So it seems that Subaru fixed a small bug in the ROM that warranted a running change in production but wasn't big enough to warrant a TSB to update existing cars? Or more likely it was just a small improvement or optimization?

Usually they are just small improvements/optimizations. Each one I have looked at so far was only calibration, no logic changes.

I would like to add a feature to the patching utility to allow a single patch to cover multiple rom revisions after it is confirmed to be only calibration changes.

There have been cases where it was a full on TSB with some major calibration changes, and I'm sure there are some that have slightly altered logic.

Using the compare utility, I couldn't identify it being a change to any of the tables, in fact the utility isn't able to compare, at least I don't know how to get it too (see attached). Even browsing through each of the tables "manually" I didn't notice anything, but I could have missed something.