Pin.pull() needs PyMCU/PyMCU#448 (HAL getter); Pin.irq() blocked on #12

[begeistert]

Update 2026-09-15: Pin.init done, Pin.pull/Pin.irq split into precise HAL/compiler tickets

machine.Pin.init(value=...) is implemented (src/pymcu_micropython/machine.py), forwarding
to the HAL's own init() which already had value/drive/alt; mode/pull's sentinel
default is now the literal -1 MicroPython itself uses (verified byte-identical to the old
255 spelling). drive=/alt= raise, matching what the HAL already does for them (this
chip's GPIO has neither a pin-mux nor a drive-strength register). This closes the
machine.Pin.init allowlist entry.

Remaining two, now precisely filed:

• machine.Pin.pull() -- needs a no-arg getter overload on
  pymcu.hal.avr.gpio.Pin.pull(), the same way Pin.mode() right below it already reads back
  what it maintains. Filed with the exact function and signature at pymcu.hal.avr.gpio.Pin.pull() has no no-arg getter overload PyMCU#448
  (milestone Peripherals).
• machine.Pin.irq() -- handler/trigger are stub-declared positional-only
  (self, /, handler=None, ...), the same compiler gap machine/micropython/time/utime can't match MicroPython's positional-only C-function signatures: the compiler has no PEP 3102 / syntax #12 already
  tracks; priority=/wake=/hard= don't map to anything on this chip (documented
  limitation), but the signature cannot match at all until / lands regardless. Blocked on
  machine/micropython/time/utime can't match MicroPython's positional-only C-function signatures: the compiler has no PEP 3102 / syntax #12, no new ticket needed.

Original report

Compared against micropython-rp2-stubs:

• machine.Pin.init(mode=-1, pull=-1, *, value=None, drive=None, alt=None) -- this layer's
  init(mode=255, pull=255) had neither value= nor drive=/alt=.
• machine.Pin.pull() -- a getter for the currently configured pull mode; only the setter
  (init(pull=...)) existed.
• machine.Pin.irq(handler, trigger, *, priority=1, wake=None, hard=False) -- this layer's
  irq(handler, trigger) has none of priority=/wake=/hard=; on this chip none of the
  three map onto anything real (documented limitation, not a gap to close).

Repo choice

machine.Pin.pull()'s getter needs PyMCU/PyMCU#448 (HAL). machine.Pin.irq() needs
#12 (compiler, positional-only /).