Two faults from the same audit. Every wire from the Core's M-Bus header
resolved to null: the kind does not start with 'esp32', so boardPinToNumber
fell through every branch and a part wired to the header never saw a signal,
with nothing anywhere saying why. A dedicated branch (like the Cardputer's)
maps the bare-number pads, sends 5V/GND/3V3/BAT to -1, and three new tests
pin it — the board had zero test coverage before.
And LEDC events now carry the carrier frequency. The engines have always
known it; LedcDuty just had no field for it, so a speaker listener could only
ever play a canned note — the Core's piano spent its life on 660 Hz. The duty
handler stashes it per pin in the PinManager (getPwmFreq), a side table
rather than a new callback parameter so the existing two- and three-arg PWM
listeners stay untouched.
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