Questions tagged [vic-20]
For questions about the Commodore VIC-20
36 questions
4 votes
1 answer
309 views
Why does the VIC-20 tinymon relocator escape $00 bytes?
Jim Butterfields tinymon1 monitor for the VIC-20 was distributed as a BASIC program with appended machine language code, as is typical for many CBM machine-language programs. However, in this case the ...
- 29.5k
7 votes
1 answer
761 views
Which computer first used stored characters (shape selector) and character bit patterns in the same memory
On the Commodore VIC-20, the VIC chip alternates between cycles where it fetches a byte from screen memory that identifies a character (and also a nybble from color memory), and cycles where it ...
- 41.2k
9 votes
1 answer
616 views
Did the Vic-20 save money using static RAM?
The unexpanded Vic-20 had 5K of RAM. This was quite small even by 1981 standards, but it was trying to be cheap enough for consumers to buy, and it succeeded, selling over 2 million units. One reason ...
- 65.3k
16 votes
2 answers
3k views
Were cartridge slots cheaper at the back?
I'm remembering a difference in the design of Commodore computers like the Vic and 64, versus the Atari 8-bits, and game consoles from the likes of Atari and Nintendo: they all had cartridge slots, ...
- 65.3k
23 votes
8 answers
5k views
Why did the VIC-20 and C64 have only 22 and 40 columns when the earlier PET had 80 column text?
When I was a kid, the "real" computers in movies looked so cool with that 80-column monochrome green text. My first computer was a VIC-20 and it always felt very "toy-like" to me ...
- 465
7 votes
3 answers
835 views
Why did the Vic-20 need special chips for I/O?
The Vic-20 used two 6522 VIA chips for I/O. I asked why it had two of them but thanks to a comment from Bruce Abbott, I now think that wasn't quite the question I needed to ask. What I really need to ...
- 65.3k
5 votes
1 answer
431 views
From what errors could Commodore's tape loader recover
The Commodore PET/VIC-20/C64 tape routines write out the leader for each file twice, and then write the data twice. While it would seem that this should allow data to be loaded more reliably, ...
- 41.2k
14 votes
3 answers
2k views
VIC-20 vs. VC20 (or VC-20)
My first computer was a VC20. Was it just renamed (for the German market?) as a VolksComputer? (I am a Finn and the VC was bought in Finland). Or were there any actual differences to VIC-20?
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