I would like to block fader movement feedback messages from DAW to controller when I move the physical fader, so that it does not fight back.
The faders do not send touch messages, so I can not use that.
I want to do it using a global variable that will be set to 1 when a fader message comes from the controller , and test this variable when fader messages come from DAW.
I want to use a onetime (not repeating) timer set to 1000 milliseconds to set the locking variable back to 0 when no faders on the controller are moved for one second or more.
Now the questions.
Do I understand it correctly, that the timer will keep restarting the 1 second interval with every fader movement update, so that the 1 second timeout will be measured from the very last fader message received? Manual says the timer retriggers, so I guess this is it, but please confirm.
Are there any race conditions and/or deadlock risks when doing this? I believe there should not be any problems, but please confirm as well.
Yes, you can, for instance, start a 1 second single shot timer upon movement of your fader. The timer will not trip until you stop moving the fader and the 1 second interval has completed. Generally I use a global variable as a “timer busy” flag. Then when receiving from your DAW you can use that flag to indicate if you want to process messages back from the DAW. You can set the global variable back to 0 when the 1 second timer trips.
Example:
Incoming (from DAW) - CC12 on MIDI CH 1 any value set to qq
Rules
// check timer busy flag
if ga==1 then exit rules, skip outgoing action.
Outgoing (to controller ) - CC5 on MIDI CH 3 value qq
The outgoing would probably look like this
Incoming (from controller) - CC5 on MIDI CH3 value qq
Rules
// don’t mess with it if it is set (just to be safe)
if ga==1 then skip next rule
ga=1
Outgoing - Timer ‘Watchdog’ 1 second delay
And another to send the fader message
Incoming (from controller) - CC5 on MIDI CH3 value qq
Outgoing( to DAW)- CC 12 on MIDI CH 1 value qq
As long as you are careful that only one translator has the ability to update the global variable at any given time you should be OK.
Steve Caldwell
Bome Customer Care
Also available for paid consulting services: bome@sniz.biz
