Date   : Tue, 16 Mar 1999 16:03:45 -0000
From   : "Fraser, Colin J" <Colin.Fraser@...>
Subject: Re: MIDI Interface

> -----Original Message-----
> From: jgh@... [mailto:jgh@...]
> Sent: 16 March 1999 12:48
> To: bbc-micro@...
> Subject: [BBC-Micro] MIDI Interface
> 
> I built a BBC MIDI interface back in '89 - it still works wonderfully.
> It's address configurable, so if I ever I found out what 
> address the AMPLE
> system expected to find a MIDI port at I could set it to it. 
> The circuit
> diagram is on PD disk JGH-007, I could post it to the group if the
> moderator agrees (3.5k).

The Music 2000 has three midi ports - all based on 6850 ACIAs.
All the necessary programming information for the 6850 is in the Advanced
User Manual.
Only one midi input is provided, but I don't believe the use of midi input
was ever implemented (?)

The three ACIAs are at &FC08-9, &FC0A-B and &FC0C-D - status and data
registers respectively.
The midi input is connected to the ACIA for output port 3 (&FC0C-D)
There are pulse stretch circuits for the activity LEDs too, but these are
not really needed.

My own midi interface (also 6850 based) appears at &FC08-9, but Ample will
not use it, so I expect it wants to see all three ACIAs at the right
addresses before it believes there is a Music 2000 present.
My own midi sequencer worked fine with the Music 2000.

Colin f