You maybe at a physical limitation for the FC and transmission over a long distance
it is a known limitation unfortunately
I did solder header pins. Right now I've only got one of the grounds connected, since they're all tied together on the FC anyhow (or so says the schematic). I wonder if the half-inch difference in return path could actually cause that sort of issue. Would surprise me.
I had a 3 meter run that I had to do recently on another project and ended using a 10' extension USB cable and it fixed my problem
you are correct they are all common on the board
I should have noted that in my situation where the grounds were split, it was not at the FC - it was at the strip where I jumped it back to the bus for all the negative terminals - I had the strip on one PS ground and the FC on a separate one - I suspect this in some way messed with the timing or something - once I had common grounds across the whole display, all of the strange flickering in that situation went away
Wish I had more to offer :(
That's odd ... same power supply, but different ground screws? (Like one of the typical-ish 5v/60A supplies w/ three grounds and three +5v?)
I am actually using 2801 LEDs for my next display due to the limitation you are hitting right now - not giving up on FC though as it has some really awesome applications - though I do wish there were a headless all in one option, but that was not part of the original design motivation I don't think - I am currently (tonight) messing with trying to get the ARTNET functionality to work with http://www.solderlab.de/index.php/software/glediator - just now reading through all of the code
Define: "headless all in one"?
meaning a controller with something like the RPzero or small form factor arduino
one thing I like about the arduino for the signs that I have lit lately is that running my configs without the FC and straight from an Arduino is much more reliable from a power on power off perspective - RP as you probably know have a huge issue with power loss - which means in addition to powering something installed for a long time PLUS providing a battery backup that shuts down the display in the event of a power failure becomes painful
Using the FASTLED libraries on an Ardiuno has become my goto for all small projects - the FC does excel for large scale projects - particularly the ingenious implementation of OPC and all of @scanlime goodness.
Much different foot print for sure - but has a lot of built in components that make doing large installs much easier it would seem - would be awesome to see where FC could be integrated into a project like this
buy this board - snap in a FC and away you go with all the ports and connections ready to roll