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View Full Version : Some 8088 action at Revision 2017



Scali
April 18th, 2017, 01:36 PM
Perhaps some of you were aware that this past Easter weekend, the world's biggest demoparty was on: Revision.
There was one release for 8088 there, it was a chipmod song using the sound routine that reenigne originally developed for the endtune of 8088 MPH. The rules required that the executable be 32 KB or less. Of course we can pack 3 minutes of music in there just fine :)
Perhaps you like it. This will run on a real IBM 5150 or 5160 provided you have enough memory (I suppose 256 KB should do it, perhaps slightly more).

https://youtu.be/L2ppIrtcD3w
I also created a 'safe' version that requires a slightly faster CPU, but uses the PIT for timing, and is therefore not sensitive to the speed of the system. This makes it more friendly for clones and emulators.
Binaries can be downloaded here: https://www.dropbox.com/s/l6s4f3bigilkoz8/SIZEMTRS_drums.zip?dl=0

1ST1
April 18th, 2017, 09:39 PM
Thanks, downloaded...

Xacalite
April 19th, 2017, 05:03 AM
Is 32KB a typical limit at today's demoparties?
From what I recall, common limits were 256B, 4KB, 64KB...
32KB looks weird.

Scali
April 19th, 2017, 05:19 AM
Is 32KB a typical limit at today's demoparties?
From what I recall, common limits were 256B, 4KB, 64KB...
32KB looks weird.

This was an "executable music" compo, so it was music-only. Even if you were to include visuals, they would not be shown.
I'm not sure if 32KB is typical for this type of compo, but they are always size-limited, otherwise you could just create a huge WAV file and stream that.
The point is that the size-limit should force you to create some kind of software synthesizer that generates the music in realtime.

evildragon
April 19th, 2017, 10:07 AM
This.....didn't quite work correctly on my model 25. Lol

https://www.youtube.com/watch?v=5NsNIThdFVM

Scali
April 19th, 2017, 10:45 AM
This.....didn't quite work correctly on my model 25. Lol

https://www.youtube.com/watch?v=5NsNIThdFVM

It works correctly, this is the expected result :)
I take it the SAFEMTRS.EXE version worked fine though?

evildragon
April 19th, 2017, 10:59 AM
I didn't even try to use the safe one honestly. I'll have to try it when I boot it up again..

Only thing was, I couldn't actually hear anything out of the model 25. The nyan cat demo is louder (but with a high pitched whine).

Scali
April 19th, 2017, 11:11 AM
Only thing was, I couldn't actually hear anything out of the model 25. The nyan cat demo is louder (but with a high pitched whine).

Well, it probably played the music WAY too fast as well, so the PWM can't do its magic.
The safe version is synced with the PIT, which should run at 1.19 MHz regardless of what CPU you have, so it should always play at the correct speed, at the cost of more CPU overhead, so you can't get by with an 8088 at 4.77 MHz.
I'm not sure how fast a machine you'd need for that particular safe version, but I have a slightly more optimized version of it, which runs fine on an 8088 clone with 8 MHz turbo: https://www.dropbox.com/s/aldvo61jaygqn8b/OPTMTRS.EXE?dl=0
So it doesn't need to be THAT much faster.

Xacalite
April 19th, 2017, 05:26 PM
Isn't the speaker in Model 25 a piezo one?
Bad for pulse-width modulation...

Xacalite
April 19th, 2017, 05:59 PM
The point is that the size-limit should force you to create some kind of software synthesizer that generates the music in realtime.
Well, just had a look at the rules: "Any platform that is able to generate sound can compete!"
Which probably means somebody could bring a 16-bit PC with some ROM-based wavetable synth card...

MicroCoreLabs
April 19th, 2017, 09:18 PM
Im surprised that nobody has posted that they liked it! This is most impressive! A very catchy and entertaining tune.. Who composed it? Did it win a prize?

Scali
April 19th, 2017, 10:42 PM
Well, just had a look at the rules: "Any platform that is able to generate sound can compete!"
Which probably means somebody could bring a 16-bit PC with some ROM-based wavetable synth card...

Well, probably not... the rules say: "This competition also supports "oldskool" PC soundcards such as AdLib and SB16." But they probably wouldn't consider a ROM-based card "oldskool". Unless it's a Sound Canvas/SCC-1 perhaps? :)
And in fact, the PC speaker was competing against things like Amigas and C64s (including dual-SID configurations). Amiga being the original wavetable platform of course.
But also Atari 2600 :)

Scali
April 19th, 2017, 10:46 PM
Im surprised that nobody has posted that they liked it! This is most impressive! A very catchy and entertaining tune.. Who composed it? Did it win a prize?

It was made by no less than 3 musicians: dLx, Vedder and Triace.
Sadly we came 13th out of 14. I think the annoying 16.5 kHz carrier wave may have had something to do with that. I wasn't there, but it supposedly was quite annoying in the party hall on the big sound system. Could have been the result of some bad encoding that made it worse than it already is.
So for next time, I'll try to alter the routine to see if we can get the carrier wave well out of harm's way (20+ kHz).