Midi Merge Technique?

[Byron G. Jacquot]

>How then should active sensing messages be handled, maybe that's
>on MIDI specs?

[this is all found in the MMA spac, page 2-32/3]

First of all, it's optional for both transmitters and recievers.  You can
just ignore it, if you want.

It's main idea was to prevent stuck notes if a controller plays a note, then
is disconnected, never to send the corresponding note off.  It makes more
sense for strap-on controllers than other situations.

The transmitting side needs to send an active sensing message ($fe) at least
every 300 ms (with a recommended window of +/- 30 ms).  A timer/interrupt
could keep this going if needed, maybe coupled to the transmitters watchdog,
if it's got one.

The recieving side should wake up not expecting active sensing, until it
sees the first $fe message, which then starts up the active sensing mode.
After that first byte, there must be following bytes at least every 300 ms
(+/- 10%).  If one of those bytes is missing, it should shut off all playing
notes (similar to an all notes off message), then wait for move valid notes.

In reality, I dont know how many instruments implement it.  I know that my
Octapad II transmits, but checking the manuals for the Juno 106 and MSQ100,
neither of them recieve it.

Anyone else have MIDI implementation charts handy for their instruments
(usually in the back of the manual), who would care to check to see if
active sensing is included?

Byron Jacquot