Problems programming the Blinky Grid

Hello, I seem to be having problems getting the Blinky Grid to display a clear message. I can see the semblance of the message or the pixel grid that I programmed, but there are several glitches in each frame. It would seem like there are some shorts or bad solder joints but I can’t find any. Is there anything you could suggest trying?

Hi Tony, sorry for the delay in getting back to you. I’m still figuring out the new Discuss “not a forum” software notification settings. Are there any LEDs that are never, ever lit? You could try programming in a solid grid pattern that might help make it easier to diagnose. Are any LEDs installed backwards? You could look to see if the flat side of the LED base is aligned with the white outline on the circuit board (for example,

Also double-check the soldering connections to the pins on the chip. Unfortunately, the complex behavior of the charlieplexing display makes it more difficult to troubleshoot, but I’m sure we’ll be able to figure it out.