fredc@petsd.UUCP (11/27/86)
> > >I want to stick a MIDI interface on my Amiga. I don't want to pay the >40 or so dollars people want for what looks like a cable. So, does >anyone have either > > a recipe for making a MIDI interface (just a schematic or so > would do nicely), or > > a source for the above. > >Reply either via the net or by mail. If I get lots of interesting mail >responses I will post a summary. Thanks a lot. > > David Hendler > > I was under the same impression you are, that the MIDI was just a cable but I decided to buy one anyway. I'm glad I did! When I got the package it came in a 15"x10"x6" cardboard box. Not having any idea what I bought, I opened the box and expected some kind of hardware about the size of an external drive. What I found was lot's of packing popcorn (and I mean lots) and a seemingly trivial RS-232 cable. I moaned and groaned a bit until I opened it up. There's a mini-circuit board inside with what I think is a uart and some other stuff. I'm not a hardware type at all so buying something that works is better then taking a chance on frying my $1300 dollar Amiga! I use the MIDI with a Yamaha DX-27 and it works great. I've tried to write some programs that read/write to the synth using the serial port but I haven't had a lot of luck. I can read from the synth keyboard and display hex MIDI sequences but they don't always seem to be what the MIDI protocol describes. When I try to write to the keyboard it just laughs at me by displaying a DATA ERROR? on the LCD. I think the problem is that MIDI is defined at 31250 baud and I'm writing directly to the SER: device. I'm not sure if it can handle the speed. The interesting thing is that software like Music Studie works great, so they must be sending Ok. I assume that they program the port directly so there is'nt any driver restrictions in there. I know this is more then you probably wanted to hear but I'd be interested in hearing about any tales of MIDI and the Amiga. -Fred Cassirer
wilkes@beatnix..UUCP (John Wilkes) (11/28/86)
In article <878@petsd.UUCP> fredc@petsd.UUCP (Fred Cassirer) writes: > .... I've tried to write some programs that read/write to the synth > using the serial port but I haven't had a lot of luck. I can read from > the synth keyboard and display hex MIDI sequences but they don't always > seem to be what the MIDI protocol describes. When I try to write to > the keyboard it just laughs at me by displaying a DATA ERROR? on the > LCD. I think the problem is that MIDI is defined at 31250 baud and > I'm writing directly to the SER: device. .... According to the ROM Kernel Manual, the serial device can be set to any baud rate from 110 to 292000. Additionally, "Although baud rates above 19200 are supported by the hardware, software overhead may limit your ability to ``catch'' every single character that should be received. The Output data rate, however, is not software dependent." You're probably trying to talk to your keyboard at the wrong baud rate, or something. Have you tried messing around with the settings in Preferences? -- John Wilkes -- UUCP: sun!elxsi!embos!wilkes USPS: ELXSI, 2334 Lundy Pl., San Jose CA 95131 # My Employer appologizes for the fact that I have access to the network. # Furthermore, my Employer disclaims any knowledge of the above ramblings, # which are clearly the product of a deranged mind.
wagner@utcs.UUCP (11/29/86)
If you want to use MIDI, it seems, from the manual (RKM-2) that one must use the SendIO(), DoIO() or BeginIO() level of support, and not the SER: device level of support. You should also read the description of the SERB_RAD_BOOGIE (love those names) bit, and some of the provisos that go along with setting it. Pg 392 in my manual. Hope this helps (it didn't mean a lot to me!) Michael Wagner (wagner@utcs)
cmcmanis@sun.uucp (Chuck McManis) (12/01/86)
In article <878@petsd.UUCP>, fredc@petsd.UUCP (Fred Cassirer) writes:
[ Actually I was going to include Fred's question here but the stupid
inews software disagreed with me as to how much of it was pertinent.
Since I was more concise in my answer than Fred was in his question I
got punished. So if you would like to see Fred's question look up
the above mentioned article, and if you can find it you will be
enlightened, if you can't you will have two reasons to be irritated
witht the Lofty Lords of News Software. Flames to /dev/null please]
Actually in my copy of 1.2 (Gamma 1, haven't got the release stuff yet)
you can select 31.25K baud from preferences for the serial device.
Then it is simply a matter of opening the device from your favorite
language (I use the C syntax fp = fopen("SER:","r+); setnbf(fp); )
then fgetc or fputc seems to work fine.
What we really need is a midi device handler but until I get a lot more
spare time than I have I will have to just wait and see.
--
--Chuck McManis
uucp: {anywhere}!sun!cmcmanis BIX: cmcmanis ARPAnet: cmcmanis@sun.com
These opinions are my own and no one elses, but you knew that didn't you.