Rethink contents of board.pins about pingo-py

[danilobellini]

That's as useful as ls /usr/bin: too much information, but it should be there. ls /usr/bin | grep python might make sense. That's what happens when one have board.all_pins and use for something like [el for el in board.all_pins if isinstance(el, SupplyPin)]

Back to a shell, one can type python[TAB] to find all Python versions available, which would be simpler. Likewise, attributes that already selects a class of highly used pins would be useful. That's probably be the case for the data pins (board.data_pins?), which includes digital and analog pins, and for digital pins (board.digital_pins?). But how about PWM pins? I²C pins? UART pins? Analog output-only pins? Pins with pull-up resistors internally? I still think that having some attribute to store the knowledge of all pins is useful.

For some pins, the easiest way to access by a name, like board.all_pins["SCL"] for getting the only I²C clock pin on it. To find if a board have such pin, a trial-and-error approach would do, but something like "SCL" in board.all_pins would be better (which would need a __contains__ for the type(all_pins) to allow pin aliases).

[Vido]

@danilobellini and @ramalho,
Thanks for your suggestion.

We have this function selection with the Board.filter_pins
This came on this (quite old) commit 55339e6

digital_subset = self.board.filter_pins(pingo.DigitalPin)