Start with two reads of the same software
A compare only means something when both files come from the same ECU family and the same software. If the software numbers differ, nearly every byte differs too, and the result tells you nothing. Check both files first: EcuInside shows the software number of each one, so you can see straight away whether they belong together.
Bytes or tables
There are two ways to compare. A byte compare lists every address where the files differ. Any binary compare tool can do it, and it works on anything, but a long list of addresses doesn’t tell you much on its own.
A table compare groups those differences into the tables they belong to, so you see which tables changed and by how much. That’s the one you want for an ECU file. EcuInside does both: it matches the tables in the two reads, and lists every other changed range of bytes as well.
How to compare on EcuInside
- Open Compare two files.
- Drop the original read in the first box and the changed one in the second.
- Read the list of changed tables, biggest change first. Open one to see which cells changed, and from what to what.
- Below the tables, look at the changed areas that sit outside any table.
Nothing is changed and neither file is kept.
Other ways
- TunerPro has a Difference Tool: you pick two files and it marks what differs. With a definition loaded it shows changes inside the defined tables differently from changes elsewhere (SR20 forum).
- WinOLS compares files too, but it’s a paid editor (EVC).
- OpenRemap compares two files from the command line, offline (OpenRemap).
Reading the result honestly
A changed table tells you that something was changed, not what it does. A factory file doesn’t carry table names, so we can’t say whether a table is boost, fuel or something else, unless a tuner has named it for that software. Then the name shows next to it.
Changed bytes outside any table can be program code or data we can’t place. And if two reads are byte for byte the same, they hold the same program.
Drop the original and the changed read and see which tables changed, by how much, and every other byte. Free, read-only, and neither file is kept.