[LAD] computer keyboard control surface update

Len Ovens len at ovenwerks.net
Thu Aug 7 17:44:38 UTC 2014

On Wed, 6 Aug 2014, Len Ovens wrote:

> I do have a question though about ardour control by midi. The Mackie IF says 
> it sends control messages that are in the form num of ticks up or down. This 
> means I should be able to have a key send ticks up and another ticks down, 
> but this doesn't seem to work.

It does work... but only into the the mackie midi in. It only seems to 
expect 0 to 100 ticks which is probably not enough for a fader anyway. 
This is probably due to physical limitations in the encoders, getting more 
than 96 or so ticks per full turn starts to get expensive real quick (10 
to 1 or so... which answers the why use motor faders question). Changing 
controls on the gui while monitoring the midi out was very informative.

> Also, It seems the master rec-enable is not toggle-able. Odd. I have tried

It is if I call myself a mackie control surface. That seems like as good a 
standard as any for mapping, though it would just be a sample config file 
and the user is welcome to create their own.

As it is not too hard, I think it is best to make fader/pitch controls 
that convert ticks to absolute value and accept the same from midi in. All 
the MIDI info I have also suggests that a controller should give a value 
between 0 and 127 so the same there. Encoders are already taken care of 
and work as is (using two key events). I have three LEDs to play with and 
will set them up as user settable, but my default will probably be Record, 
Roll and select (use all controls for stuff on a single channel)

Really, having the logic for a control surface as an application gives a 
lot of room for things a HW surface can't do.

Len Ovens

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