PWMOut Error on Raspberry Pi Pico W

[dbisu]

CircuitPython version

Adafruit CircuitPython 8.0.0-beta.4 on 2022-10-30; Raspberry Pi Pico W with rp2040

Code/REPL

import board
import pwmio

led = pwmio.PWMOut(board.LED, frequency=5000, duty_cycle=0)

Behavior

>>> led = pwmio.PWMOut(pin, frequency=5000, duty_cycle=0)
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
TypeError: Expected a Pin

Description

No response

Additional information

Using digitalio.DigitalIO(board.LED) works correctly.

[dhalbert]

The LED pin on Pico W is not a regular pin. It is accessed through the CYW43 coprocessor and its firmware, and is not available for PWM use. Real pins like the regular GPIO physical pins can be used with PWMOut. (The LED pin on the regular Pico works as you would expect.)

@jepler I am not sure if there's an improvable error message here or not.

[dbisu]

Oh, ok. I was porting some code from the Pico to Pico W. This explains the difference. I'll refactor my code that handles the LED.
Thanks.

[jepler]

switch validate_obj_is_pin to use mp_arg_validate_type and make mp_arg_validate_type print the required type, so that the error is

>>> p = pwmio.PWMOut(board.LED)
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
TypeError: pin must be of type Pin, not CywPin

?

[dhalbert]

@jepler is your last comment a suggestion? We can move this away from Support.

[jepler]

Yes, I think a simple change could improve the error message