Flickering when using multiple channels

[pierrep]

Just wanted to report that I've had some issues with the ofxDMX addon recently.

I've been using this device together with an Enttec DMX Usb Pro:
http://www.enttec.com/?main_menu=Products&pn=71003

The issue I had was occasional weird flickering when I was sending different data to each channel. I had no visual glitches when sending the same data to all four channels (testing with a sinusoidal signal).

I looked at the code but couldn't find any obvious bugs. I then swapped to ofxGenericDmx and my problems were gone.

I think it could be the serial driver vs FTDI driver....not sure really, but thought I'd flag it in case anyone else has had problems. This was on Ubuntu 12.10, 64 bit.

Also posted this here:
http://forum.openframeworks.cc/index.php/topic,7277.new/topicseen.html

[kylemcdonald]

thanks, that's really good to know. i'll leave this open in case anyone else runs into this.

[quadbyte]

I can confirm the issue on Ubuntu 13.04 running ofxDmx on my BeagleBone Black.
With a DMX projector fixture, ramping Red and Blue channel back and forth from 0..255. I get one frame where I can see the Green leds flicker, every three or four cycle.

Switching to ofxGenericDmx (harder to install due to FTDI dependencies) and the problem is gone.