I thought this was interesting. While troubleshooting my issue that is now marked 'RESOLVED' I found that each time I started sending data out (the clock Signal running) without any have any pixels light, a column was lighting. I was working on this column before noticing this so I assumed I shorted something out.
I started by unplugging the cathode for that column and surrounding columns. It still continued to light. I check everything around it for a short, didn't see to be a the case. I am puzzled as to how with only the anode plugged into the control board it was able to light up the column. Not all the leds in the column were lit.
I began to fix this (with the cathode still unplugged) un soldering LEDs until the row stopped lighting when power and single was on. In the end I replaced 5 LEDs in the column and had no further problems.
My guess is the LEDs had an internal short. I read something about the MBI / Allergro chips having a feature to identify shorts but am not sure how that works. I am still puzzled how it was able to light with only the anode hooked up.
ms
I started by unplugging the cathode for that column and surrounding columns. It still continued to light. I check everything around it for a short, didn't see to be a the case. I am puzzled as to how with only the anode plugged into the control board it was able to light up the column. Not all the leds in the column were lit.
I began to fix this (with the cathode still unplugged) un soldering LEDs until the row stopped lighting when power and single was on. In the end I replaced 5 LEDs in the column and had no further problems.
My guess is the LEDs had an internal short. I read something about the MBI / Allergro chips having a feature to identify shorts but am not sure how that works. I am still puzzled how it was able to light with only the anode hooked up.
ms