Upgraded to Arduino Due

A project log for Very large LED Display

Build 8.2 ft Serial Addressable LED Display. Will be used to display message and basic animation. Leading 4H club project

hamblin.joehamblin.joe 07/18/2019 at 01:450 Comments

We made the jump to an Arduino Due.  The reason was kept running our of resources with the Arduino Mega.  We have 2100 LEDs, even using progmem for our arrays, fonts etc we where very tight on memory.  Then we started looking at having some animation images, this put us over the limit.  The switch was pretty easy.  Luckly the proto shield I had not the Mega fit perfectly on the Duo.   I wanted everything to be soldered, nothing was going bread board, concerned about wires coming loose.  There was some house keeping had to do, the code would compile for the Arduino Uno/Mega but there where warnings, of course I ignored these.  The program would not compile for the Due.  There where three problems

   1.  Array out of bounds.  it was defined at 14, and there was a 14 character string being stored.  Simple to resolve I increase size to 18

   2.  Global defined variable conflict.  This was coming from one of the libraries we where using.  I simply added a number to the end of the variable in our code

   3.  Variable Type conflict.  We where defining our Arrays as Const Boolean but had a function that did not use the "const" definition.  Took me a bit to find it, google search was very helpful

I had to also use a level shifter, get deal for $2.95 for 9 !!

I tested this our with the LED on a small 15x20 matrix and it worked fine.  I soldered into the shield and re-routed the data line.  Very easy.  Lastly I encased the level shifter in epoxy, I didn't want to worry with it touching something inside the cabinet and shoring out.