Denial

First of all, it's not the VIC-20 that switches between PAL and SECAM, it's your display which mistakes the video signal of your VIC-20 for SECAM for some of the time. Real SECAM output requires an adapter PCB in the VIC-20. Do you own a contemporary, "non-intelligent" CRT monitor to cross...

i have the FE3 as an .prg file from the BADAPPLE demo with rev020. Please note that the Bad Apple demo comes with an own dedicated firmware for FE3: to play on VICE emulator, first add fe3badas7.5.prg as a Final Expansion cartridge. Then attach badrom7.5.d64 as a 1541 disk image. This firmware dump...

I have some source code that I would like to examine to see if I can find a bug(s) that is present (I didn't write the code). That is a somewhat strange motivation to start out with 6502 machine language, but then so be it. You might want to take a look at my VICMON primer . Only requirements are t...

https://sleepingelephant.com/ipw-web/bulletin/bb/viewtopic.php?t=10756&start=20 I've been working on my own assembler [...] That seems to be MONster , which Bryce hosts on github: MONster is an all-in-one editor/assembler/debugger for the Commodore Vic-20. The design philosophy is uncompromisin...

Screens built this way become somewhat more involved when the viewer cannot anymore tell easily that the picture was 'tiled' from characters. Here is a particularly nice example from a type-in game (Dangerous Planet): https://dateipfa.de/.Public/denial/images/games/d._planet.png These are a number o...

I still haven't figured out the separation between the Vic's screen editor and BASIC itself (like where the kernal ends and the BASIC begins from a functional point of view - such as taking the keypresses using the kernal and starting the BASIC token parsing etc). There is a clear hierarchy between...

What is put into the keyboard buffer by the KERNAL is already the fully decoded result after the modifier keys have been read and the corresponding decoding table has been chosen. You should note that the routine that does this decoding is vectored (via $028F) so a program is free to remap the keybo...

I'm assuming (MX,MY) is the center point and that A and B are the major and minor radii? Yes - to be more specific, A is the half axis in parallel to the x co-ordinate and B the half axis in parallel to y. Rounded rectangles would be neat, but that special-cases a whole bunch of pixels at the corne...

Regrettably, not perfect circles. They are perfect circles in memory, but the wild & whacky pixel aspect ratio of the VIC-20 squashes them into ovals. That, and also with regard to your inquiry about the PAR for PAL/NTSC you might want to take a sharp look at my ellipse routine (snippet taken f...

For more details, please read this post in the thread "How to reinit 16k expansion?", and to quote from there: It all boils down to what contiguous address range in RAM is available for a BASIC program and its variables, what address range of RAM is accessible for the VIC chip and whether ...

For what matters, you can always take a look at the photos I posted last year - and which I already linked to in the start post - to get a first impression of the frenzy taking place on Revision. You can reach Saarbrücken by train as follows (arriving one day earlier on Maundy Thursday to acclimatiz...

From March 29th to April 1st 2024, Revision, the world's biggest pure Demoscene event, opens its doors at the E-Werk in Saarbrücken, Germany! Since 2011, each year there were attending around 800 visitors from more than 30 countries. Main language is English, with people coming from Europe, overseas...

In first place you will need to operate VICE xvic with an emulation of the FE3 cartridge . This needs a suitable firmware image of FE3. Please check the relevant details in this post: Using FE3RD in VICE (was: Re: FE3 RAM Disk) . You'd then unpack ops' repo in a directory on the host PC and point VI...

With a cartridge as intended medium, filling up BLK1..3 and BLK5 with all ROM is the most likely scenario and supported out-of-the-box by VICE. Here's how I would fill these address ranges from disk, on real hardware: 1 POKE55,0:POKE56,32:CLR:DN=PEEK(186) 2 N$="BLK123":GOSUB6 3 N$="BL...

[...] I wonder if I have missed anything [...] LOAD in program mode does not set the pointer in 45/46 (start of variables, a.k.a. "end of program"), rather it retains the value from the program that does the load. In your case, the value of your 2-line boot program. If the chained-through...