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Path: sserve!newshost.anu.edu.au!munnari.oz.au!constellation!convex!convex!cs.utexas.edu!swrinde!elroy.jpl.nasa.gov!ncar!newshost.lanl.gov!demos.lanl.gov!jxg From: jxg@demos.lanl.gov () Newsgroups: comp.os.386bsd.apps Subject: New MPU401 MIDI driver available Date: 13 Mar 1994 02:36:29 GMT Organization: Los Alamos National Laboratory Lines: 39 Distribution: world Message-ID: <2ltu7d$nmk@newshost.lanl.gov> Reply-To: jxg@demos.lanl.gov () NNTP-Posting-Host: nash.lanl.gov I have uploaded my Roland MPU-401 driver to freebsd.cdrom.com. It is in a file called mpu401.tar.z. (For anybody who doesn't know what the mpu401 is, then you probably don't care either. It is a MIDI coprocessor for driving musical synthesizers.) The driver takes advantage of almost all of the coprocessor. All the other drivers that I have seen only use the circuit as a UART (including the mpu driver bundled in the sound driver). There are advantages to using the coprocessor - mostly to reduce load on the operating system (MIDI is a 31.25 Kilobaud serial protocol) and to reduce the affect of interrupt latency on sequenced music. (Although this might not be a big deal. Adagio doesn't have any problems.) Hannu Savolainen is currently implementing some of the same features to be included in a later release of the sound driver. I don't really know what all he is doing, but it might be a while before we see it in FreeBSD. This doesn't really affect the current sound driver. Hannu's driver can handle all kinds of PC soundcards as far as actually synthesizing sounds and provides MIDI support for the soundcards as well. The mpu is only used to drive external synthesizers and has no sound capabilities of it's own. Both of these drivers can be used in the same kernel and even the same application. (It works for me.) I haven't really messed with the MIDI functions in Hannu's driver, so I can't say much else about it. By using the coprocessor, much of the work of implementing a full blown sequencer is already done in hardware. The early DOS sequencers worked this way. I and some others are really anxious to get some music applications going for unix. I have started work on a sample editor, but I don't know of anybody yet working on a interactive sequencer. If you decide to try it out and find any bugs, let me know. I am womanless for another couple of months, so I will can right on it. I will probably look at any problems the same night that I get any mail. john galbraith jxg@demos.lanl.gov