Diff'ing .D81 files

Just jotting down some quick notes of how I went about diff’ing .d81 file changes from Git via Beyond Compare and a bit of scripted use of c1541 and petcat (with Jimbo’s patch applied to it).

It’s not perfect, a little buggy, can be improved, but it does the job for me now…

Beyond Compare - D81 File Format settings

The “c1541.bat” file consists of the following:

C:\Users\GurceI\Downloads\WinVICE-3.2-x86\c1541.exe -attach %1 -dir > %2
if exist \Users\Gurcei\disk2\ (
  rmdir /s /q \Users\Gurcei\disk1
  rmdir /s /q \Users\Gurcei\disk2
  md \Users\Gurcei\disk1
  cp %1 \Users\Gurcei\disk1\
  cd \Users\Gurcei\disk1
  C:\Users\GurceI\Downloads\WinVICE-3.2-x86\c1541.exe -attach %1 -extract
) else if exist \Users\Gurcei\disk1\ (
  md \Users\Gurcei\disk2
  cp %1 \Users\Gurcei\disk2
  cd \Users\Gurcei\disk2
  C:\Users\GurceI\Downloads\WinVICE-3.2-x86\c1541.exe -attach %1 -extract
  cd \Users\Gurcei
  start bcompare.bat \Users\Gurcei\disk1 \Users\Gurcei\disk2
) else (
  md \Users\Gurcei\disk1
  cp %1 \Users\Gurcei\disk1/
  cd \Users\Gurcei\disk1
  C:\Users\GurceI\Downloads\WinVICE-3.2-x86\c1541.exe -attach %1 -extract
  cd ..
)

Beyond Compare - .PRG / .C65 settings

TODO: This’d work much better if c1541 extracted out prg files with a .prg extension (instead of just leaving the extension blank by default).

Usage

Once these two file formats are set up, and your git config is configured to diff via beyond compare, the next time there’s a modification done to a .d81 file you could assess it with a command like:

git difftool MEGA65.D81

This will bring up two beyond-compare windows:

Window 1: A diff of .d81 dir-entries as text

Window 2: A directory-diff of all extracted prg files

…and then you can dig a bit deeper into a diff of basic 65 .PRG files too

TODO: Would be nice if one day we also had a disassembly differ too 😃