You might want to take a look at this thread: VIC20 NTSC > PAL Conversion.
The OP links to a document on zimmers.net: PAL VIC20 Goes NTSC (just backwards).
Search found 4673 matches
- Fri Mar 08, 2024 2:11 am
- Forum: Hardware and Tech
- Topic: What do I need for a NTSC to PAL conversion on a short board?
- Replies: 1
- Views: 585
- Fri Mar 08, 2024 2:03 am
- Forum: Emulation and Cross Development
- Topic: Reverse Engineering of JETPAC for VIC-20
- Replies: 12
- Views: 1650
Re: Reverse Engineering of JETPAC for VIC-20
doneMike wrote:[T]hat clearly positions this thread into the "Emulation & Cross-Development" section, as it concerns the use of tools that don't run on the VIC-20 itself.
- Tue Mar 05, 2024 6:00 am
- Forum: General Topics
- Topic: ** Revision 2024 Invitation / Website
- Replies: 18
- Views: 2307
Re: ** Revision 2024 Invitation / Website
The video of the invitation intro is online on YT: https://www.youtube.com/watch?v=fdB3Ell9F1M
Enjoy!
Enjoy!
Re: ELITE
Hi, Meryt, [...] it's really ground my gears all my life that there's no version [of Elite] for the VIC. I understand why. The bitmapping makes it next to impossible. [...] it is not quite clear to me what led you to that false assumption. The VIC-20 is very well capable of doing bitmapped graphics!...
- Mon Mar 04, 2024 1:38 am
- Forum: Programming
- Topic: Screen Management
- Replies: 3
- Views: 514
Re: Screen Management
[...] the value of X could not be higher than the fateful 255, [...] ... yet people have managed to work with the 65xx being an 8-bit CPU all the time. Please check out my VICMON primer thread for standard idioms to address into the screen. If it's just the matter of initialising the screen content...
- Wed Feb 21, 2024 1:09 am
- Forum: Hardware and Tech
- Topic: VIC20 with NOS 6561 sound problem
- Replies: 4
- Views: 521
Re: VIC20 with NOS 6561 sound problem
Even though bigger memory expansions shift things around on the VIC-20 (notably, BASIC memory and text/colour RAM), the behaviour and position of I/O (VIC and VIA) remains unchanged. a 35K RAM expansion (which I think pages in the cart memory over the built-in SRAM unless anyone can say different) T...
- Mon Feb 19, 2024 12:08 pm
- Forum: General Topics
- Topic: Jeff's VIC 20 Book
- Replies: 268
- Views: 29497
Re: Jeff's VIC 20 Book
This is a tip: To plot the cursor on position x,y on the screen: X position is on allocation 211 decimal and Y on 214. But it doesn't work because what is needed is a print HOME and a PRINT after POKE 214,Y-1. It took me hours to find out. I found the answer in Compute!'s Gazette of december 1983. ...
- Mon Feb 19, 2024 10:53 am
- Forum: Programming
- Topic: Can the display window be re-triggered? (was: 9001 when read?)
- Replies: 8
- Views: 896
Re: Can the display window be re-triggered? (was: 9001 when read?)
Warning by viznut/pwp, for example.heaven6502 wrote:And which demo[s] use that bus trick?
- Mon Feb 19, 2024 5:51 am
- Forum: Programming
- Topic: Can the display window be re-triggered? (was: 9001 when read?)
- Replies: 8
- Views: 896
Re: Can the display window be re-triggered? (was: 9001 when read?)
what if I do racing the beam and set $9001 later so it compares more often to $9004? As I wrote: you can't restart [the display window] after it ended by writing a corresponding higher value into $9001 ... I was always wondering how 4mat did stuff (like in C64 terms) FLD like tricks in his VIC20 in...
- Sun Feb 18, 2024 4:28 pm
- Forum: Programming
- Topic: "Free ZP" which ones?
- Replies: 6
- Views: 484
Re: "Free ZP" which ones?
Many of the new graphics modes pioneered by tokra and me routinely use the entire ZP, stack and OS workspace (i.e. $0000..$03FF) for graphics data. The only thing that necessitates the use of ZP are the two indirect-ZP address modes, and maybe the odd cycle saved with ZP (instead of ABS) operands. P...
- Sun Feb 18, 2024 3:47 pm
- Forum: Programming
- Topic: Can the display window be re-triggered? (was: 9001 when read?)
- Replies: 8
- Views: 896
Re: Can the display window be re-triggered? (was: 9001 when read?)
No. The display window is only triggered once per frame (when $9004 compares equal to $9001), i.e. you can't restart it after it ended by writing a corresponding higher value into $9001. What you *can* do is filling part of the display window with characters in multicolour that use %01010101 (85 dec...
- Sun Feb 18, 2024 3:56 am
- Forum: Games
- Topic: Multiplayer VIC20 Games
- Replies: 6
- Views: 882
Re: Multiplayer VIC20 Games
Especially unexpanded for extra charm. What's the point of advocating the use of an essential non-standard hardware extension and at the same time 'disallowing' the use of RAM expansions? No - it wouldn't add any 'extra charm' to me. It just places an unnecessary restriction on any related endeavou...
- Sun Feb 18, 2024 3:44 am
- Forum: Programming
- Topic: "Free ZP" which ones?
- Replies: 6
- Views: 484
Re: "Free ZP" which ones?
$2A $52 $FB - $FE I wouldn't be that sure about $2A and $52. Even though there are no direct ZP operand fields of instructions in the BASIC interpreter that point to these two addresses, these two addresses are part of temporary float values (actually their 5th byte) and might be referenced by indi...
- Sun Feb 18, 2024 3:33 am
- Forum: Programming
- Topic: "Free ZP" which ones?
- Replies: 6
- Views: 484
Re: "Free ZP" which ones?
Just $FB..$FE, actually.heaven6502 wrote:what are the ZPs which are really free?
...
You find more details in this post of mine.
- Thu Feb 15, 2024 1:41 pm
- Forum: Programming
- Topic: Playing better notes
- Replies: 1
- Views: 395
Re: Playing better notes
You probably mean this one: 10-Bit Oscillator Frequency Resolution