1 (edited by Shiru 2021-08-22 20:26:38)

Topic: Squat for Atari

Here it is, the source code for CA65 assembler, my song from Silly Venture 2K20+1 in 1tracker format, and SquatM engine for 1tracker that has an option to export CA65 compatible data (but Z80 version plays in the tracker).

More unnecessary details at Patreon, like (now) usual. Don't be afraid to visit it, it is not behind a paywall, I'm just running a public blog there.

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Re: Squat for Atari

:-) thanks

I was on SV, your song got a lot of applause

Re: Squat for Atari

Hi Shiru

I can't get the tune to load into 1tracker, it errors.

I've copied the squatm.1te into the engines folder, is there anything else to do ?

Re: Squat for Atari

No probs, I've sorted it now. I was using v0.29 rather than v0.30

Very impressive tune

Re: Squat for Atari

Thanks, guys!

Yeah, better to keep 1tracker up to date to use newer engines. Not that it changes terribly, but it does get updates and fixes time to time (now as I'm using it by myself more often).

website - 1bit music - other music - youtube - bandcamp - patreon (latest news there)

Re: Squat for Atari

Awesome, thanks for the hard work and the great write-up, Shiru. And not least congrats on composing such a kick-ass tune.

I faintly remember trying to code something for GTIA some years ago and also being frustrated by the not-so-stellar documentation available. I wonder if there are any GTIA-specific tricks one could pull here. The basic mode of operation is to write a value < 8 to 0xd01f to set the beeper on, else it's off, right? Did you discover anything beyond that?

Re: Squat for Atari

Thanks!

No, I barely managed to get this basic on/off stuff to work properly in time for the compo, so I didn't investigate it further than that. I guess there can be more, and in general Atari XL/XE platform is worthy enough to pay more attention in regards of the 1-bit stuff.

website - 1bit music - other music - youtube - bandcamp - patreon (latest news there)

Re: Squat for Atari

utz: you need to turn off the screen (DMA off) and turn off the NMI interrupts because during its execution the CONSOL (1-bit sound) register is reset, IRQ should also be turned off and possibly read the keyboard directly. there are no restrictions beyond these guidelines.

Re: Squat for Atari

Shiru: maybe another engine? maybe you can add export for Atari to 1tracker as well?

Re: Squat for Atari

There is export for this SquatM engine, but it only exports an assembly source with DBs. I sure would like to eventually get to a proper support, with a built-in 6502 assembler and XEX export.

As for porting other engines, we'll see. I think it is a good to bring some more of the finest ZX developments to the Atari platform.

website - 1bit music - other music - youtube - bandcamp - patreon (latest news there)

11

Re: Squat for Atari

xxl, what is the timing for the interrupts? If we had some fast interrupt reset CONSOL each scanline, for example, then this could actually be useful for PCM/pulse-interleaving playback.

12

Re: Squat for Atari

1/50 sec. NMI interrupt (vertical blank interrupt also performs other operations and thus takes a long time)

if you use interrupts then you can use IRQs to interrupt playback loops to reload counters but regular loop works well too

Re: Squat for Atari

Offtopic somewhat, but got 'High Orbit' sounding beautifully on the VZ200 (Z80).

I passed your link to a TRS80 Coco fan (he is a 6809 guru), and he is going to attempt to port it over.

Thanks Shiru.