slightly OT, JX-8p

[WeAreAs1 at aol.com]

In a message dated 11/13/99 4:05:27 AM, you wrote:

<<A Roland PG-800 Can be used as well.  However, It might be like the
JX-3P, where the programmer and Midi cannot function at the same time,
but I don't know for sure.>>

No, unlike the JX3P and PG200, the PG-800 can be used simultaneously with 
MIDI.  Apparently, Roland was using the serial communication lines of the MCU 
in the JX3P to do double duty, so it had to switch between either MIDI input 
or PG200 input.  Later, on the MKS30 (the rackmount version of the JX3P), 
they added an additional serial interface adapter chip, which only had to 
deal with serial data.  This chip arbitrated between the MIDI data and 
programmer data, then sent the total data to the main MCU, allowing the JX to 
read both signals simulataneously.

Most of the later model Rolands that had companion programmer units (the 
MKS80, D50, MKS50, D20, etc.) actually used their regular MIDI Input jack as 
the programmer input (with an additional merging MIDI Input jack on the 
programmers, for connecting your keyboard controller).  Those programmer 
units were simply sending MIDI sysex data, unlike the proprietary data 
formats used in the PG200 and PG800.

Michael Bacich