Migrating a 'mixed' arcade folder from one retropie install to another

rbaker

@Chillimonster Why not just clone the card?

Chillimonster

Current build is 3.7,

Dont like doing the upgrade script and prefer to perform clean formats (OCD and all that) so when 4.0 drops i want to be able to move all across with little fuss.

Chillimonster

Transfering the files to a 3.8.1 build does not work and i have to re-assign the neo-geo roms individually.

Does 3.8.1 store the runcommand allocations somewhere differently? Or in a different format?

dankcushions

as far as i know /opt/retropie/configs/all/emulators.cfg is the file.

what happens when you create a new association? do you see a new entry appear on this file along with all your old ones?

Chillimonster

@dankcushions

I will check when i get home as i've started a fresh 3.8.1 build before i came to work and copied the roms over but not the .cfg file ready for me to have a play later.

I was hoping i could just copy the .cfg file over for an easy life ;-)

ben_thatmustbeme

@Chillimonster just did a little digging
/opt/retropie/configs/all/emulators.cfg uses an md5 checksum of the system it is trying to run it with and the path to the rom. So make sure the path to the rom is exactly the same and whatever emulator the arcade folder is defaulted to is the same.

Chillimonster

@ben_thatmustbeme said in Migrating a 'mixed' arcade folder from one retropie install to another:

@Chillimonster just did a little digging
/opt/retropie/configs/all/emulators.cfg uses an md5 checksum of the system it is trying to run it with and the path to the rom. So make sure the path to the rom is exactly the same and whatever emulator the arcade folder is defaulted to is the same.

Thanks for the insight - very useful information.

So..... could the updated emulator binaries have an effect on the checksums in the hash files, causing the roms not to run on the new system?

ben_thatmustbeme

@Chillimonster no
it literally does this, and i ran this manually to confirm
/etc/emulationstation/es_systems.cfg
under n64 has
<command>/opt/retropie/supplementary/runcommand/runcommand.sh 0 _SYS_ n64 %ROM%</command>

it will take the third and forth options and jam them together and do the md5sum of that. I checked it and

echo 'n64/home/pi/RetroPie/roms/n64/Goldeneye.v64 ' |md5sum
gave me the same hash as my file.

So if
/etc/emulationstation/es_systems.cfg and /opt/retropie/configs/all/emulators.cfg and the files are in the exact same path, and named the same, you should be good to go.

Chillimonster

@ben_thatmustbeme

Thanks for taking the time to find this out for me - i would have been lost!

Will confirm the positions of the files are the same across 3.7 / 3.8 / 3.8.1 later when i get out of the workshop.

BuZz

I guess it could be improved to just hash the system name and filename without path. I did that code some time ago, and I didn't really think about a case where roms may be moved to another path etc. Changing it would break backward compatibility though, unless it checked for old and new hash etc. Maybe it would be easier to just use a human readable key. system_romname (removing spaces and so on). I might revisit this at some point.

BuZz

PS. I have moved this thread to help/support