[Coco] DriveWire does MIDI

Gene Heskett gene.heskett at gmail.com
Fri May 21 10:36:49 EDT 2010


On Friday 21 May 2010, Aaron Wolfe wrote:
>At the cocofest, Brian Schuhbring showed me his MIDI setup which he
>used to play music throughout the event. We talked about using CoCo as
>a MIDI player, and of course I wondered if DriveWire could be used.
>Turns out it can.  By renaming one of the virtual channels to 'MIDI'
>and adding some code to redirect its output to the synthesizer built
>into the Java VM, I've got "mfplayer" working pretty well.  I'd expect
>that any other program which uses a MIDI device in OS-9 would work as
>well.  I also added MIDI file detection to the /N handler, so you can
>dump
>any standard MIDI file to the /N port and it will play on the PC.
>
>There is some latency at times.  I have ideas on how to reduce if not
>eliminate this.  I'm also going to explore having the server pass the
>MIDI events on to an external keyboard or synthesizer the way Brian
>does with his setup, which would provide much nicer sounding
>instruments.   There are ways to load different sound banks into
>Java's internal synth too, that might be interesting.
>
>Here's a video of DW4/MIDI in action:
>http://www.youtube.com/watch?v=F2VXN1zIt_g
>
>So now we have disks, printing, clock, virtual modems, tcp/ip
>networking, and MIDI running on the built in bitbanger.
>
>The CoCo rules :)
>
Awesome.  This bitbanger is turning into quite a workhorse. 

17 or so years ago, I had a modified rs232 pack and the bitbanger both 
working with Ultimuse, driving my two cheap keyboards.  I have forgotten how 
I did it now (blame it on CRS), but I was feeding each keyboard with only as 
many channels as it had voices, 4 for the Casio MT-whatever and 8 for the 
CZ-101. But both of those have succumbed to dead battery damage, so I need to 
find a new, better one than either of those were.

I may have a tin ear for latency problems as the demo above didn't seem to 
suffer badly enough to get my attention.  In any event, the demos latency 
problems were totally swamped by pulseaudios latency problem as it takes 
pulesaudio about 2 or 3 minutes to get its stuff in one sock when playing 
that from a cold start. Pulse is getting better on linux, but it still has a 
long way to go before it is 100% transparent.

Thanks Aaron, great demo.

>-Aaron
>
>--
>Coco mailing list
>Coco at maltedmedia.com
>http://five.pairlist.net/mailman/listinfo/coco
>


-- 
Cheers, Gene
"There are four boxes to be used in defense of liberty:
 soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
You are so boring that when I see you my feet go to sleep.



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