BBC Micro on Pi400 running RetroPie

lonestar

I have recently installed RetroPie on a Pi400 and got some C64 and PET games working. Thank you to those who contributed to this project and made it possible.

Since, once upon a time, I had a BBC Micro, I wondered whether there was an emulator for this machine. It seems there isn't one by default in RetroPie. However, I came across this script:

https://www.stardot.org.uk/forums/download/file.php?id=99372&sid=51bffcc819121a6d040fd3f423e47460

It seem that it ran OK for most part and downloaded then compiled the emulator. However, something went awry towards the end because I ended up with an empty es_systems.cfg file. Fortunately I have been able to recover from this and now have a working Emulationstation with the C64 and PET emulators running again. However, there is no entry for the BBC Micro.

Based on what I could ascertain from the above script and with a little help from the RetroPie documentation, I manually created a new system section in es_systems.cfg which looks like this:

<system>
    <name>bbcmicro</name>
    <fullname>Acorn BBC micro</fullname>
    <path>~/RetroPie/roms/bbcmicro</path>
    <extension>.uef .ssd</extension>
    <command>/opt/retropie/supplementary/runcommand/runcommand.sh 0 _SYS_ bbcmicro %ROM%</command>
    <platform>bbcmicro</platform>
    <theme>bbcmicro</theme>
</system>

I also copied a couple of the .ssd files from /opt/retropie/emulators/b-em-allegro4/discs to ~/RetroPie/roms/bbcmicro, but the emulator still does not come up in Emulationstation. Likely I have got something wrong in the system definition as this was something of an educated guess on my part. For example, I don't quite understand the <command> field and how it is actually mapped to the emulator in the /opt/retropie/emulators path.

Does anyone have a working BBC emulator in RetroPie and could I request they post a copy of their system configuration in es_systems.cfg? Does there need to be a separate configuration for the Master?

Any further insights would be appreciated.

mitu

...
I also copied a couple of the .ssd files from /opt/retropie/emulators/b-em-allegro4/discs to ~/RetroPie/roms/bbcmicro, but the emulator still does not come up in Emulationstation. Likely I have got something wrong in the system definition as this was something of an educated guess on my part. For example, I don't quite understand the <command> field and how it is actually mapped to the emulator in the /opt/retropie/emulators path.

The command is not that important for EmulationStation to show the system and the game within. Check 2 things:

replace the path with the full path (/home/pi/RetroPie/roms/bbcmicro. I don't think ~ is expanded here.
make sure your .ssd files have a lowercase extension, Linux filesystems are case sensitive. Add .SSD to the list of exensions for the system just to be sure.

lonestar

@mitu said in BBC Micro on Pi400 running RetroPie:

replace the path with the full path (/home/pi/RetroPie/roms/bbcmicro. I don't think ~ is expanded here.

You were quite correct. Putting in the full path made a difference. On lauching Emulationstation I got the BBC Micro option with the Acorn logo and artwork. When I selected that I initially got a prompt asking me which emulator I wanted to use (BBC Micro or BBC Master). I selected BBC Micro and the emulator started and the first .ssd "disc" was loaded. I checked, the extension was lower case for both files, but it is worth bearing in mind.

I made some further progress by setting up a second system profile for the BBC Master. I didn't get prompted to select the emulator this time and it took me a while to find the configuration file where this is configured. All that was needed was to change the 'default' setting to point to the already configured Master option. There seems to be no artwork provided for the master so I ended up creating some on a similar theme using the artwork for the Micro as a starting point.

I encountered one rather unusual problem with the artwork. I used Inskape to edit the .svg artwork files supplied with the emulator and discovered that Emulationstation does not show any text that was added using fonts (XML <font> tag). Perhaps that explans why all text in the artwork has been created with each individual letter created as a <path> object., i.e. a polygon. When I followed this original approach, drawing each individual letter (which took some time), everything then appeared as it should. I do find it a little odd though.

The good news is that I now have both emulators working from RetroPie.

The Master didn't like one of the items on the demo disc - a demo of some window manager. Maybe I need to select the 512 emulation as opposed to the 128? Will need to experiment with that. In the meantime I will need to do some work to convert my existing .mmb file to .ssd files. I will then be able to try some games.