JVIC: New web-based Commodore VIC 20 emulator

Posted by lance_ewing 8 hours ago

Comments

Comment by davepdotorg 3 hours ago

Guess it’s time to finally type this out again: https://www.davep.org/misc/grid-bike/

Comment by aenis 1 hour ago

Nostalgia overload.

I got a Commodore/PLUS 4 - With almost no games (just Saboteur, Jet Set Willy and Booty), and my father taught me how to program in Basic 3.5 - and before I was 10 i was making trainers with 7501 assembly learned almost by trial and error. I knew back then what I wanted to do in life and followed that path to the fullest extent.

Comment by Eggpants 2 hours ago

Young me remembers fondly poking and peeking system memory locations to see what happens. The manual, if I remember right, had a table of memory locations to system settings. Things like font and background colors.

I made a “punch out like” boxing game in basic where the background color blocks was the opponent and the font lines was your character via poking memory locations.

It was slow but I was just a kid at the time. It definitely told me what I wanted to do for a living at an early age.

Comment by lance_ewing 2 hours ago

Exactly the same story with me. I got my VIC 20 when I was about 10, in the mid 80s, and that is how I learnt how to program and how I knew what I wanted to do as a career.

Comment by technothrasher 1 hour ago

Add me to that list, though my Commodore machine was a PET 2000. In fact, I was young enough at first that all I could do was remove lines from other people's basic programs and see what happened. It all grew from there.

Comment by lance_ewing 1 hour ago

I probably started the same way. I remember spending forever typing in BASIC games from magazines and books from the local library. They never worked straight off, so a bit of "debugging" was usually required, i.e. spot the typos.

Comment by mixmastamyk 1 hour ago

Interesting, did similar. But there was no information available to me about working on them for a living in the early 80s. Only the movie Wargames, which while cool didn’t seem like a realistic path, nor did it pay. Didn’t figure it out until a full decade later.

Comment by lance_ewing 1 hour ago

Maybe at 10 years old, I wasn't thinking much about working, but the VIC 20 started me on the programming path, with an IBM PC being our next home computer a few years later.

Comment by Eggpants 1 hour ago

Definitely helped that I just missed the punch card era. I know young me would have dropped my stack of cards many times…

Comment by pipo234 3 hours ago

Nice to have this, though I personally find Matt Godbolt's web-based BBC emulator more exciting (and useful)

https://bbc.xania.org/

Comment by lance_ewing 2 hours ago

Yeah, that one is a great online emulator. I've played around a bit with that one. I have fond memories of the BBC Micro from my school days, especially the game Castle Quest.

How does it handle being run on a mobile phone? My main focus with JVIC was to try making it as easy as possible to use on mobile devices, although I'll admit that my testing has only been on Android so far. I haven't tried it on iOS yet.

Comment by pipo234 1 hour ago

Castle Quest - an impossibly hard game (to modern standards). I spent so many hours only to die and start al over once more. Great fun!

My Android phone is way too old and slow to load jvic, unfortunately. Let alone jsbeeb.

But works great on my 2013 laptop when plugged into a wall socket!

Comment by lance_ewing 59 minutes ago

Yeah, it was very difficult, but a lot of fun. We used to book the school library's BBC Micro out after school and spend an hour or two each day trying to beat it. I still remember working out how to use the torches to guide the little men to walk into the room with the spider, and how to escape from the prison cell. - I'd love to try porting this game to the VIC 20 at some point. Same cpu, but the VIC's graphics are more limited. Still, with some of the tricks that people use in some of the games and demos for the VIC, maybe something similar could be achieved. Pitfall for the VIC 20 is really impressive, graphically, given its on the VIC 20:

https://vic20.games/#/pitfall

Comment by p0w3n3d 1 hour ago

So everything is web-based today I guess? But why? Is this about programming language? Packaging?

Comment by B1FIDO 3 hours ago

  THI5 1Z A WAY-K00L BBOARDZ D00DZ!!1!

  B1FF
    ...B1FF ... B1FF ?!

   ... ... B1FF B1FF B1FF BB0ARDZ!1

   B1FF ... ... ... B1FF!

  D0EZ THI5 MEAN MY BR0THER CAN KEEP HIZ OWN Vic-20 NOW??!?!????!!!


   ... BIFF B1FF B1FF D00DZ!!1!

Comment by lance_ewing 8 hours ago

The code and instructions on how to use it are here: https://github.com/lanceewing/jvic

Comment by pjmlp 2 hours ago

In LibGDX, that is great!

Comment by lance_ewing 1 hour ago

Yeah, libGDX is my go to now for web-based emulators and interpreters. JVIC is the third one I've written now. The other two are JOric and AGILE:

https://oric.games/

https://agi.sierra.games/

They all use the GWT html target. I realise that there is now also a TeaVM target. I might try converting JVIC to use TeaVM at some point.

Comment by pjmlp 1 hour ago

I still remember when it used to be all the rage before Unity and Unreal took off, especially in Android indie games.

Comment by lance_ewing 1 hour ago

JVIC (the libGDX version of JVIC) actually started out as mainly an Android project 10 years ago, but I didn't release it at that time. It was only a few months ago that I decided to add the html platform as a target, tidied it up in general, and thought it was time to release it. Given that this html version can be installed as an app on android phones, I'm not sure I need the android target anymore :D. It avoids the whole play store / app store process.

Comment by empressplay 4 hours ago

Neat, but crashed when I tried to load Frogger

Comment by lance_ewing 2 hours ago

In what way did it crash? What browser and device did you try running it on? - There might be an issue where its possible to start typing before the program load sequence has finished, e.g. where it has queued a "RUN" command for when the disk load has finished, but if you start typing before that, it might interfere with that RUN. I have an idea on how to fix that, if this is the issue. Just need to ignore key presses until all program load commands have been processed.

Comment by drzaiusx11 3 hours ago

Sounds authentic

Comment by lance_ewing 1 hour ago

Do you mean specifically the Frogger game? Or in general? - If you mean in general, it hopefully does sound very close to the original VIC 20. I actually reversed engineered the VIC chip schematic from photos of the silicon chip, so the sound emulation is based on what I worked out from the reversed engineered schematic. Some of my discussion on that is covered here:

https://sleepingelephant.com/ipw-web/bulletin/bb/viewtopic.p...

Comment by drzaiusx11 48 minutes ago

That's awesome! I had access to an electron microscope at my last makespace and always wanted to decap a simple chip for reverse engineering. A close friend of mine did that with a SID and recreated it in verilog with good results, which I always found fascinating. Great work on the VIC20 side! And yeah, my VIC20 was never the most stable machine, crashing frequently but I also had a bunch of janky expansion boards attached so ymmv...

Comment by waldrews 6 hours ago

That's one maxed out RAM configuration. Back in my day, we had 4k RAM, about 3500 bytes usable from BASIC, and that was enough, unless you were rich enough to have a 3k memory expansion cartridge. But really, if you need that extra 3k, you're just not writing code efficiently enough, right.

Comment by lance_ewing 2 hours ago

Back in the 80s, I was lucky that my father was an electronics design engineer, so he built a 24K expansion cartridge for us. I agree that there were some great games for the unexpanded VIC 20 though, such as Rockman. I loved that game. So many levels for a small game.

Comment by drzaiusx11 22 minutes ago

I had a home brewed ram expansion board (still do actually, in a box somewhere...) I powered everything up a couple years ago when my kids found it and asked what the heck it was. Still works