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16 bit fader on virtual cconsole

Posted: Wed Feb 03, 2021 6:38 pm
by Myself514
I have a 16 bit parameter and I want to assign this to a virtual fader on the virtual console. How can I do that?

Re: 16 bit fader on virtual cconsole

Posted: Thu Feb 04, 2021 3:41 pm
by lighthacker2020
Short answer after a quick search of the forum: https://www.qlcplus.org/forum/viewtopic ... lit=16+bit

Longer answer:
It'll involve some work on your end to make this happen. DMX being a purely 8 bit system, which means you'll need to chop up that value and feed it to 2 different fixture channels. Many fixtures that support pan and tilt functions do this by having a coarse channel and a fine channel, and logic inside the fixtures electronics combine these in to the 16-bit value used to position the head.

QLC+ sliders (generally) control a single channel; it can control many, but they will all change in unison (all channels get the same slider value). Which means it isn't as simple as assigning 2 channels to the same slider and getting the result. For a 16-bit value, the 2 channels need to function independently (each step in the "coarse" channel can combine with any value in the "fine" channel). It may be possible to do this directly in QLC+, but it would likely involve defining scenes for all 65536 possible values in the 16-bit range. A more tenable solution would probably be to use an external program to manage the 2 8-bit DMX values in to the 16-bit value you want to use. The "logic" part of this is easy, it's simple bit shifting, it's feeding the value back and forth which could get tricky. It may or may not be appropriate to take that 16-bit value and try to squeeze it in to a single 8-bit DMX value for the slider, no matter which way to go with it, you are losing resolution of the value.

You may or may not be trying to do something using DMX with this setup, but QLC+ at it's core is DMX controlling software, so you'll need to work within those boundaries. A bit more info on 8-bit and 16-bit can be found here http://www.thedmxwiki.com/dmx_definitions/8_bit_16_bit

If you provide more details about how and where this 16-bit value is coming from, folks might be able to help you with some more targeted suggestions.

Thanks,

Mike

Re: 16 bit fader on virtual cconsole

Posted: Fri Feb 05, 2021 8:53 am
by GGGss
Quick and dirty -> create a fixture and abuse the pan or tilt feature for your 16b channel.
Make it HTP (default in LTP mode).
Now internal QLC+ logic will keep track of your fine channel values.
But ... I imagine that the VC fader isn't going to be precise enough for you to experience those small differences.