So I got working ages ago some 7219s working on my breadboard on a matrix. very simple only required one passive and that was a resistor from 5v to pin 18 (sets the voltage for the leds) I chose 22k (Worked fine).
I want to externalise the matrix so I soldered on wires to the matrix to then a breadboard. I then use the 3 wires straight from the breadboard to the arduino. (And of course power and ground). When I do this I sometimes get a flicker. But nothing stays. I think this tells me that maybe the signals integrity or something is reducing over the wires(bare in mind there not long only 20 cm project wire). I was wondering if anyone could think of any additional components to add to increase my luck? Its not my soldering as Its hard to get it wrong. (Just wires from matrix directly into the IC)
I hope there is something that can be done and if wire does affect it (hopefully not) I am using 7/0.2 Wire ( very nice wire
Thank you for reading, ill look forward to see what i can do.