Denial

That's just amazing! I'll have to make myself a 35k expansion I think, and try it on the real thing!

When I look at the character ROM glyphs, I can see easy correlation between the letters and the shift key symbols associated with them: dzIYRhB.png The difference between A and the spade is 97 - 65 = 32, the difference between S and the heart is 32 The CBM key characters don't seem to follow the sam...

groepaz wrote: ↑Mon Feb 05, 2024 3:30 pm you shouldnt have to wait, it takes 16 machine cycles to fill the lfsr with 1 bits:

I think I need to clock the Vic at least 1 cycle first though. The way my code was working, it was setting register values before the very first cycle - and that's why it would never work.

yes it requires "enabled" being zero (for some cycles) to start. which it is after reset. vic_sound_machine_init( 44100, VIC20_PAL_CYCLES_PER_SEC ); //POKE( 36874, 230 ); //POKE( 36875, 220 ); //POKE( 36876, 0 ); POKE( 36877, 220 ); POKE( 36878, 15 ); Yup. If I wait 2 seconds and then do ...

groepaz wrote: ↑Mon Feb 05, 2024 3:23 pm Sorry, i interpreted wrong what you wrote...

yes it requires "enabled" being zero (for some cycles) to start. which it is after reset.

I'll load it up and give that a try.. stay tuned..

groepaz wrote: ↑Mon Feb 05, 2024 3:16 pm 1 AND 1 is 1, not 0

Correct but 1 ^ 1 is 0

bit 0 of gate4 is either 0 or 1 on each iteration, and ORed into the LFSR ... so thats how 1 bits go into the LFSR int gate3 = (gate1 ^ gate2) ^ 1; // Always 1 int gate4 = (gate3 & enabled) ^ 1; // ( 1 & 1 ) ^ 1 -> 0 I can only see this working if enabled is 0. I wonder if I'm setting enabl...

What doesn't work though? (That it sounds different is quite expected - there should be a thread somewhere around here about the new reverse engineered LFSR) also the quoted code is missing some lines? it should be: int bit3 = (noise_LFSR >> 3) & 1; int bit12 = (noise_LFSR >> 12) & 1; int b...

I've spent most of the morning trying to get the latest white noise generation code to work from VICE (I have a Windows SDL app and I've borrowed the sound generation code from the VICE source). I noticed the old code I'd borrowed from VICE 2.2 didn't sound the same when doing POKE36877,220 with VIC...

Here are the book listings if anyone is interested:
http://www.vic20listings.freeolamail.co ... arted.html

Along the way, I found this treasure trove: https://web.archive.org/web/*/http://archive.6502.org/publications/icpug/* Interesting...! https://i.imgur.com/7Jp9oUv.png I found a Getting Started with you ZX Spectrum book which was pretty much the same. I just remember Dad picking up this book from a ...

Using the monitor in VICE is a good way of understanding how this all works. Or my own app :-) I can see what's happening now: 0000(0000) 31 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 1............... 0000(0000) 31 30 00 00 00 00 00 00 00 00 00 00 00 00 00 00 10.............. 0000(0000) 31 30 20 ...

JSR CRNCH ; crunch keywords into BASIC tokens JMP LAB_C7E1 ; go scan and interpret code [/code] The line ends at the NUL following the line number, everything after is just part of the original ASCII text before tokenization. Right, so this is the result of the CRNCH routine? 89 20 31 30 00 Probabl...

The BASIC interpreter calls CHRIN in the KERNAL to fill the input line buffer from the input. The first call of CHRIN stops the calling program, switches on the cursor and remains in the screen editor until the user enters the line with the RETURN key. Then CHRIN returns with the first character on...

you try to draw conclusions from the document that are not in any way backed by what is actually the case: That's just the iterative questioning process I follow. I guess I'm just not that smart or have limited intelligence or time to invest in my projects. I am by no means a Vic purist so whatever...