I’ve been looking through the source code to try to figure out how to remap or increase the resolution of the blue LEDs. Since I found out that it uses a single PWM method for all the colours I have hit a wall. I was wondering if anyone has had any luck with alternative ways of defining colours or driving the LED matrix on the Meggy Jr. My desired end result is having more control over colour balance.
The issue is that the blue LEDs are very bright. You can use the same range as the other LEDs, but tend to overwhelm them if turned up all the way.
The library itself is an editable file. Open it up, and look at how it works. It uses C code very similar to that on the Arduino front end. ( Arduino/libraries/MeggyJr/MeggyJr.cpp and MeggyJr.h)
There are various ways that you might approach the issue, for example keeping the blue LEDs off in every other refresh cycle– if you did that, you would automatically dim them by half, increasing the useful resolution by a factor of two.