Handling PS1 Save Games for RetroArch
So I recently finished Resident Evil: Director’s Cut, and I wanted to play around with the unlimited weapons you get from clearing the game with certain requirements. However, since I was too lazy to try and beat the game under three hours or on the Advanced Mode, I decided to see if I could download a save game for RetroArch to do it. It took some doing, but I managed to figure it out. I posted my process in a Discord, and I was asked to archive, so I’ve copied it here.
By default, Beetle PSX uses the 'Libretro' setting for save files, meaning that each save file will be saved as an '.srm' You can switch it, however, to the 'Mednafen' setting, wherein the saves will be in '.mcr' format. I was able to download '.gme' save files from GameFAQs, but those won't work directly with BeetlePSX, so they have to be converted. I used this program, MemcardRex (https://shendosoft.blogspot.com/2014/01/memcardrex-18-released.html) With it, I was able to convert the '.gme' into a '.mcr.'
The part I struggled with was getting the game to recognize the file. What you have to do is set Beetle PSX to use the 'Mednafen/.mcr.' format, then reset RetroArch and run the game again, so it can generate the memory card files. Two files are generated, depending one your settings; one for each memory card. They are displayed as such.
𝚁𝚎𝚜𝚒𝚍𝚎𝚗𝚝 𝙴𝚟𝚒𝚕 - 𝙳𝚒𝚛𝚎𝚌𝚝𝚘𝚛'𝚜 𝙲𝚞𝚝 - 𝙳𝚞𝚊𝚕 𝚂𝚑𝚘𝚌𝚔 𝚅𝚎𝚛. (𝚄𝚂𝙰).0.𝚖𝚌𝚛 𝚁𝚎𝚜𝚒𝚍𝚎𝚗𝚝 𝙴𝚟𝚒𝚕 - 𝙳𝚒𝚛𝚎𝚌𝚝𝚘𝚛'𝚜 𝙲𝚞𝚝 - 𝙳𝚞𝚊𝚕 𝚂𝚑𝚘𝚌𝚔 𝚅𝚎𝚛. (𝚄𝚂𝙰).𝟷.𝚖𝚌𝚛
The '.0.' and the '.1.' between the game name and the file extension are important, since you want take the downloaded save game you converted with MemCardRex, and rename exactly like that, with the numbers in place. The number refer to the memory card index, with '0' being Slot 1, and '1' being slot 2, by default. From there, you take your converted save file, and drop it into the save game folder in the RetroArch directory, making sure to overwrite the original.
You might want to back up your original save files in a different folder when doing this, and you may want to make sure you copy them back into the RetroArch saves folder instead of moving them directly, as I ran into an interesting issue, related to save-states.
So I had the thought to make a save-state, and see if I could switch my save system back to the LibRetro system, and save with my own personal save games. I moved my save games back into the RetroArch save games folder, and loaded up the state. However, I found that my save games were not there, just the save from the file I downloaded. If you make a save-state on a game with save files present, those save files are retained with the save-state. I deleted the save files out of the folder, and when I started up the game, there were no save files found when attempting to load a game from the main manu. However, when I loaded the state and went to the save/load screen, the save files were there. Even when I quit out and started the game again, I went to 'load game' and the save files had returned. Be sure to take care when using save-states that you don’t lose or overwrite your save.