[LAD] midi beat clock

m.wolkstein at gmx.de m.wolkstein at gmx.de
Sat Feb 20 12:14:37 UTC 2010


hi, thx to all. i learn something more.
in my case i was only interested on midi clock. but now i plan to make a flexible standard
implementation in this way.

hydrogen will support midi clock as slave and master.
as slave hydrogen receives:
midi clock (0xF8) 24midi clocks in every quarter note,
midi start (0xFA),
midi stop  (0xFC),
midi continue (0xFB),
to snap to songpositions if status is stop h2 get position informations via song position
pointer(spp) (0xF2).

as master, hydrogen sends information in the way it receive the information's.
if internal sequencer is stopped hydrogen sends spp.
if people arrange songs with complexer beats than 4/4, all involved sequencers have to know the timeline.
e.g 3/4|4/4|3/4|7/8| and so on.

i think user interface can looks like this.
status led blinks in quarter notes. red as master, green as slave.
for humans the led can blink yellow or what ever on each first quarter into a bar. 
two check-boxes or buttons switch all conditions.
button one can toggle the whole midi clock on/off.
button two switch between master/slave.

more words over syncing the playback you can find here.
http://www.blitter.com/~russtopia/MIDI/~jglatt/tech/midispec.htm
i will use this specs as reference.

greetings wolke 




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