kmk_firmware/kmk/circuitpython/matrix.py

50 lines
1.8 KiB
Python

import digitalio
from kmk.common.abstract.matrix_scanner import AbstractMatrixScanner
from kmk.common.consts import DiodeOrientation
class MatrixScanner(AbstractMatrixScanner):
def __init__(self, cols, rows, diode_orientation=DiodeOrientation.COLUMNS):
# A pin cannot be both a row and column, detect this by combining the
# two tuples into a set and validating that the length did not drop
#
# repr() hackery is because CircuitPython Pin objects are not hashable
unique_pins = {repr(c) for c in cols} | {repr(r) for r in rows}
if len(unique_pins) != len(cols) + len(rows):
raise ValueError('Cannot use a pin as both a column and row')
self.cols = [digitalio.DigitalInOut(pin) for pin in cols]
self.rows = [digitalio.DigitalInOut(pin) for pin in rows]
self.diode_orientation = diode_orientation
if self.diode_orientation == DiodeOrientation.COLUMNS:
self.outputs = self.cols
self.inputs = self.rows
elif self.diode_orientation == DiodeOrientation.ROWS:
self.outputs = self.rows
self.inputs = self.cols
else:
raise ValueError('Invalid DiodeOrientation: {}'.format(
self.diode_orientation,
))
for pin in self.outputs:
pin.switch_to_output()
for pin in self.inputs:
pin.switch_to_input(pull=digitalio.Pull.DOWN)
def _normalize_matrix(self, matrix):
return super()._normalize_matrix(matrix)
def raw_scan(self):
matrix = []
for opin in self.outputs:
opin.value = True
matrix.append([ipin.value for ipin in self.inputs])
opin.value = False
return self._normalize_matrix(matrix)