This is a generic API for synchronously bit-banging data on a pin.
Initially this adds a single supported encoding, which supports controlling
WS2812 LEDs.
Signed-off-by: Jim Mussared <jim.mussared@gmail.com>
machine.time_pulse_us() is intended to provide very fine timing, including
while working with signal bursts, where each transition is tracked in row.
Throwing and handling an exception may take too much time and "signal loss".
So instead, in case of a timeout, just return negative value. Cases of
timeout while waiting for initial signal stabilization, and during actual
timing, are recognized.
The documentation is updated accordingly, and rewritten somewhat to clarify
the function behavior.
Jim Mussared
Damien George
Paul Sokolovsky