[rec.music.synth] SoftMacMIDI

shri@ccs1.cs.umass.edu (H.Shrikumar{shri@ncst.in}) (01/12/90)

Hi,

[Attn: people on RMS -
I am still looking for a used Yamaha FB-01, anybody got one or know
anybody who is willing to sell. I need one fast.  pls e-mail or phone.]

But to get to the subject ...

   I understand that typically a RS-232 to MIDI box is used to 
interface MIDI to a Mac. I also believe that the box is usually smart
and does some timing etc. locally.
 
   Due to various reasons I cannot use such a box. On the other hand
my needs are very simple too, compared to a performing musician.
I wish to use a MacII to just input and output MIDI data - ie. I
am not too worried about timing messages etc. and I dont expect more
than some note-on note-off messages and a few sys-ex (for the FB-01).
I am assuming that these do not generate much MIDI bandwidth since I 
expect to have just one FB-01 connected to the MacII.

   I believe the Mac has a USART which allows external clocking. My 
question specifically is - 

1. Can the USART be persuaded to generate 31250 baud 8 bit no-parity
serial data, (which is what MIDI requires) by software tricks only ?

2. Or can it be done by feeding an external clock at 31250 Hz. to the USART ?

If this can be done, a the serial port can be interfaced to MIDI with just
the optoisolator for the RS232 voltage to 5ma current loop standard of MIDI.

Anyone done this ? Thanx in advance for comments/ideas.

-- shrikumar ( shri@ccs1.cs.umass.edu, shri@ncst.in (413)-549-1836 )