Make LED_BUILTIN definition available for Arduino Due, Zero and Circuit Playground

[hlovdal]

Updates to CHANGELOG.md will trigger conflicts for this branch (led_builtin.m, rebased on top of master) when #338 is completed (or if this is done first, then #338 will get conflicts).

There is an alternative branch led_builtin applied in series with other branches that does not have those conflicts when #338 is completed. Let me know if you rather want that one merged (later).

[ianfixes]

Can you confirm that the defined value should be 13 for these platforms? If not, can you open an issue for us to look into that later?

[hlovdal]

Ok, I'll check (later).

[hlovdal]

Confirmed. Adding

static_assert(LED_BUILTIN == 13, "not 13");

to main.cpp and compiling with

~/arduino-cli compile --fqbn arduino:avr:circuitplay32u4cat .
~/arduino-cli compile --fqbn adafruit:avr:circuitplay32u4cat .
~/arduino-cli compile --fqbn adafruit:samd:adafruit_circuitplayground_m0 .
~/arduino-cli compile --fqbn arduino:sam:arduino_due_x .
~/arduino-cli compile --fqbn arduino:sam:arduino_due_x_dbg .

all succeeds.

(package install steps from here)

[ianfixes]

Thanks for checking, I really appreciate it!