Opening a .PRG file with Atari ST, Hatari Core

[retrogaming]

Hi, I am using the Hatari core and trying to open a Music Disk from here:

STay4Evr by Cream

Once the STAY4EVR(Final).zip is expanded the files include a .prg file.

If I try to open this in Retroarch it gives me a choice of: Atari Jaguar, Commodore or Scumm cores, but no Atari ST.

I am not too familiar with Atari ST software, so this is probably down to my lack of knowledge, but I think you can either boot an ST game etc., or some would load from the TOS.

I am guessing this .PRG needs to load from the TOS, but I am not sure how to boot into TOS?

If I load the Core first there is no option to Start the core.

The core has all the BIOS files etc. installed (and verified) that are required.

Perhaps I need to have a hard drive file for Hatari, and then the .PRG would need to be copied to that before I can run it?

I am hoping someone could please help?

[thingsiplay]

I just could load up a .prg file and run it and listen to some demo music from the linked file.

Disclaimer: I am not familiar with Atari ST or Hatari and discover things as I write this up. .stx files on the other hand run normally without these steps. So I recommend .ipf or .stx instead.

There is probably a better and more direct way to do this and this is just a proof that this works at all. First, .prg files contain only the code without being executable bootable by itself (think of .sh or .bat files, that’s my understanding). So you can’t run them by themselves and Hatari core does not support loading them like a Rom too. The extension .prg is not listed here: https://docs.libretro.com/library/hatari/#extensions

The main menu of Hatari itself (not the one in RetroArch) can be opened up with the START button on my controller. Select button switches some joypad modes, so you may need to experiment. L button on my controller will show some indicators.

Here comes the convoluted way, my apologies, I don’t know any other at the moment:

1. Unzip the STAY4EVR(Final).zip into a folder in your native operating system into any directory you want. I mean before you run any emulator.
2. Load up Hatari core with any game. Because I not sure how to load without a game.
3. Press START on controller to open up the main Hatari menu.
4. Go to menu entry “Floppy disks” and click EJECT on Drive A: (and Drive B: if there is something).
5. Then go back to main menu and into “Hard disks” submenu.
6. Click BROWSE on the “GEMDOS drive”. Search for the directory select it.
7. Go back to main menu. On the left bottom switch from “No Reset” to “Reset machine” and click OK.
8. The desktop of the operating system inside Hatari should open up. click Hard disk, to open the filemanager.
9. Just double click the .prg file and it should start. The first file in the root of the directory STAY4EVR.PRG gives me an error message, but in the subdirectory PARTS double clicking the .prg files will load them up.
10. Here only the keyboard works. ARROW keys up and down to select a tune and ENTER to start the song playing.

Be aware of the RetroArch Game Focus mode, so that your keys go through the emulator and are not interpreted by RetroArch. Default is SCROLL_LCK key to toggle game focus. In example without focus, the key F will be interepred by RetroArch to fullscreen, or the key F1 opens the RetroArch menu. However, if you are in Game Focus mode toggled on, these keys (and all other) are ignored by RetroArch and the emulator Hatari sees them only.

[retrogaming]

thank you @thingsiplay

I managed to get it working thanks to your detailed instructions!

In the internal menu of Hatari I changed the system to STE and changed the memory to 2MiB and then reset.

I opened the STAY4EVR.PRG, which then opens what looks like a C64 emulator (I did have to pick something convoluted), once there I typed:

LOAD"*",8

And then

RUN

and it loads!

Thanks again

EDIT: just to add, I also found HxC Floppy Emulator toolkit:

GitHub - jfdelnero/HxCFloppyEmulator: HxC Floppy Drive Emulator toolkit

You can create .st floppy images (and other formats) and then choose what files to add to the floppy image.

Then if you open the .st file in the Hatari Core and there are no bootable files on the disk it loads the TOS and then you can load the files from the .st image there.

[thingsiplay]

I thought so there would be some program like that to create a bootable media. And nice that you got the main program to run too. Reading its readme file, this is an old C64 demo. So yeah, it seems like a C64 emulator in the Atari ST emulator in RetroArch; you got to have to love that. BTW you can set the RAM setting in RetroArch too, in case the other setting inside Hatari is not persistent.

Unfortunately, I seem to have broken something. Because doing the exact same procedure as I described earlier doesn’t load the .prg folder anymore, but the .stx game runs fine. To me this is not a big deal and I don’t have the nerves to troubleshoot right now.

[retrogaming]

Thanks again @thingsiplay

I did wonder if the internal settings were not persistent as when I reset I noticed the System defaulted back to ST.

You can probably fix whatever you may have broken by removing the Hatari folder from Retroarch’s Config folder.

I am now tinkering with a hd image I found… so many things to waste my time with now