I have a C64 motherboard, and I used it to practice my desoldering skills when I got my desoldering iron earlier this year. The first chip I took out was a character ROM. I managed to remove it cleanly, and I put it in my office desk drawer.
Cut to now. I noticed that the Commodore 64 character set is different from the VIC-20's. Yeah, I'm sure everyone in the world knows this. I just never really thought about it. So, I fished out the extracted character ROM, popped it in my minipro, and read it like a 2732. This sort of worked, in that I got the top half of the normal character set and the top half of the reverse character set in the bottom half ($800-$fff) of the image.
I suspect this happens because one or more of the address lines are different between the ROM and a real 2732 (see viewtopic.php?f=11&t=9497&p=109459&hili ... ng#p109450). There's probably no way to get everything (lowercase, etc.) from the minipro, because its focus is on chips that can be burned. For example, there's no 2332 device in its library.
But anyway, it's fun to play with. The C64 character set looks nice enough on a VIC-20, and I might steal it for use in a game at some point. It probably needs to be chunky like this on a 40-column screen. The VIC-20 character set might look a bit wispy on a C64. For the record, I think the VIC-20 letters are more elegant.
Playing with a Dead C64
Moderator: Moderators
- chysn
- Vic 20 Scientist
- Posts: 1205
- Joined: Tue Oct 22, 2019 12:36 pm
- Website: http://www.beigemaze.com
- Location: Michigan, USA
- Occupation: Software Dev Manager
Playing with a Dead C64
VIC-20 Projects: wAx Assembler, TRBo: Turtle RescueBot, Helix Colony, Sub Med, Trolley Problem, Dungeon of Dance, ZEPTOPOLIS, MIDI KERNAL, The Archivist, Ed for Prophet-5
WIP: MIDIcast BASIC extension
he/him/his
WIP: MIDIcast BASIC extension
he/him/his
- chysn
- Vic 20 Scientist
- Posts: 1205
- Joined: Tue Oct 22, 2019 12:36 pm
- Website: http://www.beigemaze.com
- Location: Michigan, USA
- Occupation: Software Dev Manager
Re: Playing with a Dead C64
(Would this C64 character ROM work as expected if I simply popped it into a VIC-20? My character ROM probably isn't socketed, but I'm curious...)
- orion70
- VICtalian
- Posts: 4341
- Joined: Thu Feb 02, 2006 4:45 am
- Location: Piacenza, Italy
- Occupation: Biologist
Re: Playing with a Dead C64
I personally find the C64 character set on the VIC better than the native one. I never really liked the VIC's "wireframe" characters: they add to the general "toy computer" look and feel .