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Old October 25th 19, 12:39 AM posted to alt.windows7.general,microsoft.public.windowsxp.general,microsoft.public.win98.gen_discussion
Paul[_6_]
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Posts: 41
Default archaeology! MIDI keyboard with joystick interface?

J. P. Gilliver (John) wrote:
(I'm using Windows 7, but have included the other two 'groups for
reasons that will become evident!)

I was explaining about MIDI (musical) keyboards to a friend, when I
remembered I had one, that I'd hardly used. I dug it out - it's still in
its box, even with its original plastic bag - 3 octaves, mini size keys.
"evolution MUSIC WIZARD".

However: it has a 15-pin male connector on the end of a lead coming out
of it!

Looking into things, it would appear that that originally connected to
the joystick port on a soundcard.

I've had a look around, and I can't find anything to connect this to
USB. I've found gameport to MIDI - those seem to consist of four
connectors: a male 15 way and a female 15 way, and two five-pin male DIN
plugs (the sort that was originally used for [mostly Philips] audio
equipment in the 1970s, and early PC keyboards). I _think_ these are
just passive cables - no electronics. I've also found USB to MIDI -
these I think _do_ have electronics in them; they mostly also end in two
male DIN plugs (the electronics in a little lump in the cable), but one
or two are a little box with a couple of female DIN sockets.

If I have to go that way, can I talk to it by using one of each of these
- or, does anyone know of a single adapter (that has 15-way female to USB)?

Looking at the excellent http://www.hardwarebook.info/, it looks as if
MIDI (http://www.hardwarebook.info/MIDI) is just two wires - a current
source and a current sink - plus a shield.
http://www.hardwarebook.info/PC_Gameport_with_MIDI seems to support that.

And before anyone says - yes, I know I could probably get a second-hand
USB MIDI keyboard for less than the price of the two adapters! But I
like a challenge.

And, whether I get the old keyboard working or buy a new [or
second-hand] one, (a) will I need drivers for a MIDI keyboard, or does
Windows 7 know about such things intrinsically, and (b) any suggestions
for good free MIDI editing/recording software? I rather suspect the
software that's with the keyboard won't work with Windows 7, as it says
I need at least Windows 3.1 (-:


This shows an example of buffering (with the 74LS00 uses as a driver to
drive the 220 ohm resistor). And there is an optoisolator on the Midi-In
side. Implying that perhaps someone is concerned about ground differences
in the equipment, eroding the TTL noise margins if the opto wasn't there.

http://midi.teragonaudio.com/hardware/pc_intfc.htm

In this example, they show a TTL-level serial port running at 31250 bps.

https://www.compuphase.com/electronics/midi_rs232.htm

So a USB to serial port, with the level shifter removed, would
be base materials. You can get USB to TX/RX/GND for wiring up
to smartphones, as an example. The article warns though, that
not all serial ports can be programmed for 31250. Maybe 38400
would be the closest baud rate. They mention some FTDI chip
as being a candidate. You would then search Ebay for a serial
port with TTL levels, based on that FTDI chip. Such an adapter
comes with a cable, with three wires with the ends stripped,
for "soldering to circuits". Typically, people use such adapters
for tapping into the serial port on a router board, or the serial
port on a hard drive controller board (pins on the outside, in
the jumper block, do serial!).

The remaining part then would be, how do you convince a serial
driver, to be adopted as MIDI I/O. Not a clue...

At least you're going to have a hobby... or a research project...

Paul