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Posted: 05 Jan 2018, 09:28
by Ken29
Hi, this is a good one, how do I detect Null data ? I explain :

I have a sysex message coming from a machine remote. Only the fourth digit matters.
I have one button play and I want to use it as play or pause.
It's clear in the data flow, there's no signal [-1], between two hits, but this Null data isn't detected and the display array sees only the first hit. Thus, the first "3" is send to the BUS and then nothing happens.
"Has changed" doesn't work, it doesn't see the null data has a change...

I could reset the array with a timer but it is really not elegant...

Cheers

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Posted: 05 Jan 2018, 23:47
by 23fx23
there is a dedicaced module "Is NULL" in patching that detects null flows

Posted: 06 Jan 2018, 13:13
by Ken29
Thanks for your answer, but for some reason, "Is Null" doesn't see Sysex messages as datas and the Null output stays on "1"...

PS : it is not totally exact, on time on twenty Sysex hits, Is null detect it.... So strange...

Kenan

Posted: 06 Jan 2018, 14:58
by 23fx23
mm thats strange indeed. ive no sysex device to test here, but altervanitely think you could use a midi filter module set to sysex messages, wich would outputs pass or rejects pulses.

i don't undersnt exactly what should go to your sysex bus aftewards to, it should be 3 on a receive and 0 otherwise?

Posted: 06 Jan 2018, 19:02
by Ken29
Good guess 23fx23, the midi filter detect the Sysex.

The patch works,I now have 3 on receive and 0 otherwise.

Previously, because of the null between the sysex messages, the output of the Display Array was never changing when I was hitting several times the same button...

Best

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Posted: 06 Jan 2018, 22:58
by 23fx23
good if that work :)
can't test here but here is a possible alternative way (maybe you ll need the same wait module out of pass).
the get array element value would scan the index 3 of sysex (since array pos are 0,1,2,3 its the 4th data where your '3' comes from), multiplied by the 1 pulse on receive make 3, or 0 when not receiving.

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Posted: 07 Jan 2018, 12:10
by Ken29
It works except you have to plug the "Midi In" Sysex out to the "Filter" midi In, else you will never trigg the filter...

Posted: 07 Jan 2018, 12:26
by 23fx23
oh ok yes, interesting to know thanks