On Thu, Aug 06, 1998 at 10:10:49AM -0700, Ted Lemon wrote:
> 
> Cool!   How do you get a com port to be a MIDI port, BTW?   I mean, do
> you have a circuit that you wired up, or is there a dongle you can buy
> that does the job?   Also, how do you get the UART to run at the right
> baud rate?

the MIDI rate is, I think, 31250 bps.

Amiga mainboard hardware can do it bretty closely (about 0.5% off);
on AmigaOS, 31250 bps is a standard value in the serial preferences
editor.

com hardware with a 4x standard clock (e.g., the Amiga "HyperCom"
board series but also some "high performance" PC boards) can do
it, too, at less than 2% error.

I think Sparc hardware would have a less then 2% error.

BUT

you need opto couplers, anyway (I think, demanded by the spec)... so, as 
you NEED a hardware dongle, you can integrate back-to-back UARTS to transform
the bitrate. Needed, e.g., for standard com hardware.

Standard com hardware would have an error of 8.5%, which is probably too much.
As far as I know, there are ready to use dongles, which integrate the opto 
couplers and back to back UARTs, to do the translation.

Regards,
	Ignatios