[LAD] midi beat clock

Arnout Engelen lad at bzzt.net
Sat Feb 20 15:40:25 UTC 2010

On Sat, Feb 20, 2010 at 01:14:37PM +0100, m.wolkstein at gmx.de wrote:
> 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).

Hydrogen is already a JACK Timebase Master and Slave. However, a quick glance 
suggests it does not emit BBT information when acting as a Master, and does not
understand it when acting as a slave - i might be running a slightly outdated 
version though.

If Hydrogen could be extended to produce (should be doable) and understand 
(harder, but should be doable) JACK BBT information, the MIDI stuff could be
implemented as a separate JACK application that is not directly tied to 

Looks like Gabriel's http://www.teuton.org/~gabriel/jack_midi_clock/ already 
implements one side of such a bridge.

Such a solution would certainly be more complex, but also more flexible 
compared to building this into hydrogen completely.


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