The V3 Proffieboard has a Status led. That LED can provide a fair amount of information about what the board is doing. Let this page be your decoder wheel for understanding what it's doing.
If the LED is blinking (not pulsing) then it's trying to show you an error code. The number of blinks tells you what the error is, according to the following table:
The LED will be off if the saber is completely idle in order to save power.
When the saber is doing something, the LED will be pulsing. The speed of the pulse will tell you how busy the saber is. If it's pulsing fast, then the saber is working hard, if it's pulsing slowly, it is not.
When USB is connected, the shape of the pulse will change from a triangle wave ( ⋀⋀⋀⋀ ) to a sawtooth wave ( ⩘⩘⩘⩘ ).
When ignited, the brightness of the LED will increase.
When charging, there will be an extra "blip" every 2 seconds on the Status LED.
So to summarize:
Triangle Pulse (fade in, fade out) = USB is not connected. Pulse is faster when the CPU is busy.
Sawtooth Pulse (fade in, fade in) = USB IS connected. Pulse is faster when the CPU is busy.
It’s brighter when ignited.
Brief blinks every 2 seconds when charging.
If you don't like how the Status LED behaves by default, you can add #define NO_STATUS_LED to your config file. Then you can add a blade to control the status LED like this:
SimpleBlade<CH2LED, NoLED, NoLED, NoLED, StatusLEDPin, -1, -1, -1>()
Blade styles should then use Green or White to drive the Status LED.