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Support Forum » Problem with LED Array Kit

May 29, 2011
by Mick_Richards
Mick_Richards's Avatar

When first hooked up it randomly flashed all over the board. After some time the whole thing stopped. I have tried every combination with the "col" and "row" wires to no avail. The voltage regulator is putting out 4.9 volts. The microcontroller wire points are all putting out 1.4 volts. All wires on the LED board are reading 2 volts. Further the LCD display unit was functioning normally - it now will only display 20 rectangular patterns. Have I damaged the microcontroller? If so where do I go from here?

May 30, 2011
by Rick_S
Rick_S's Avatar

The LED Array project is one that was real popular about a year and a half ago when the tutorial was posted on the site. So there are lots of posts regarding it going back to October '09 thru probably January '10 that you could probably get a lot of good info out of. That said, it definately sounds like a wiring problem. If you get your row wires attached to the coulumn outputs on the micro, I'm pretty sure the LED display will go totally blank.

As for the LCD problem, if the 1st and 3rd rows are a line of black rectangles and the 2nd and 4th are not, that usually indicates a wiring problem there as well. Typically if the display isn't getting proper data to initialize it, that's what you get.

So my advice would be to step back, and start from scratch. Strip your board, build the basic circuit from the guide with the LCD, load the initialload program and see if the LCD works. Once that circuit is know good and working, then remove the LCD and connect the LED display per it's guide.

If you still have problems, good photo's of your wiring will help us help you much more.


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