visual glitches/2600

[jp48]

Hi all,

 

I put this same question here (not sure if Batari Basic group is correct one).

 

OK, I have more specific example, from Atari 8-bit machines. There are a bunch of variations of short 32b demo, assembly loop here:

loop
   lax 20 
   ora 19
   tay
   sta $d200,y 
   eor $d40b
   sta $d000,y
bvc loop 

Reading system timers, bit manipulated, and putting to values to POKEY, VSYNC etc.

Anything similar to 2600 ? It doesn't need to be 32b, with proper headers etc, but similar principle, reading (semi)random timer(s), bit manipulation(s), and sending to VSYNC or similar. Glitchy graphics, which run long, any examples, would be used as visuals to chiptune gig.

Thanks !!

Edited February 27, 2016 by jp48

[iesposta]

Hi all,

 

I put this same question here (not sure if Batari Basic group is correct one).

 

OK, I have more specific example, from Atari 8-bit machines. There are a bunch of variations of short 32b demo, assembly loop here:

loop
   lax 20 
   ora 19
   tay
   sta $d200,y 
   eor $d40b
   sta $d000,y
bvc loop 

Reading system timers, bit manipulated, and putting to values to POKEY, VSYNC etc.

Anything similar to 2600 ? It doesn't need to be 32b, with proper headers etc, but similar principle, reading (semi)random timer(s), bit manipulation(s), and sending to VSYNC or similar. Glitchy graphics, which run long, any examples, would be used as visuals to chiptune gig.

Thanks !!

 

Yes.

I have examples.

Most are music with a graphic effect.

Can not yet find the one I am thinking of that goes really crazy with the screen (and its music evolves and changes, always different, and I listened and watched for a long time).

 

These 2 are 128 byte music. The 4K one is the first 128b repeated out to 4K.

genmusic1.bin

genmusic2-4k.bin

 

Lots of these: Song Player Main Music (2003) (Paul Slocum).bin

[iesposta]

Hi all,

 

...

 

Glitchy graphics, which run long, any examples, would be used as visuals to chiptune gig.

Thanks !!

 

 

Found it: Transmat.bin

 

 

P.S. This is the best Atari 2600 TIA chiptune I've heard: !salvotheme.bin

[Thomas Jentzsch]

Hi all,

 

I put this same question here (not sure if Batari Basic group is correct one).

 

OK, I have more specific example, from Atari 8-bit machines. There are a bunch of variations of short 32b demo, assembly loop here:

loop
   lax 20 
   ora 19
   tay
   sta $d200,y 
   eor $d40b
   sta $d000,y
bvc loop 

Reading system timers, bit manipulated, and putting to values to POKEY, VSYNC etc.

Anything similar to 2600 ? It doesn't need to be 32b, with proper headers etc, but similar principle, reading (semi)random timer(s), bit manipulation(s), and sending to VSYNC or similar. Glitchy graphics, which run long, any examples, would be used as visuals to chiptune gig.

A problem is, that without coding the 2600 doesn't produce a valid video signal. So you need quite some extra bytes.

 

Also, there is no built in ROM, so there is nothing you can base your glitches on. You have to produce everything from scratch.

[jp48]

 

 

Found it: Transmat.bin

 

 

P.S. This is the best Atari 2600 TIA chiptune I've heard: !salvotheme.bin

Thanks, very coool !! Looking glitches pretty much like this, do you have source code ? (I need only visual part, if it is possible to extract).

Edited February 27, 2016 by jp48

[jp48]

A problem is, that without coding the 2600 doesn't produce a valid video signal. So you need quite some extra bytes.

 

Also, there is no built in ROM, so there is nothing you can base your glitches on. You have to produce everything from scratch.

 

I am looking of source code examples, I have dasm + Batari + Harmory cart, I don't need built in ROM, I am making that myself. Just looking code snippets (asm, Batari Basic) for similar kind of glitchy visuals, perhaps using timers, and it doesn't need to be short (no byte limits except 2600 own), with proper headers etc.

 

Thanks !

[jp48]

OK, checked Transmat with disassembler, exactly what I needed, I am able to adjust/change whatever I need, making variations of it and compile with dasm.

 

Thanks !!

[TheHoboInYourRoom]

You might not still need this, jp48, but anyone else who's interested can find transmat's source code from its pouet.net page: http://www.pouet.net/prod.php?which=61492

[jp48]

Thanks Hobo, this is helpful, writing a new version with some additional stuff, using BatariBasic. Nice to compare disassembled version to original, I am not assembler guy, though can read and understand it.