src/adafruit_blinka/microcontroller/generic_micropython/spi.py

   1 # SPDX-FileCopyrightText: 2021 Melissa LeBlanc-Williams for Adafruit Industries
   2 #
   3 # SPDX-License-Identifier: MIT
   4 """SPI Class for Generic MicroPython"""
   5 from machine import SPI as _SPI
   6
   7
   8 # pylint: disable=protected-access, no-self-use
   9 class SPI:
  10     """SPI Class for Generic MicroPython"""
  11
  12     MSB = _SPI.MSB
  13     LSB = _SPI.LSB
  14
  15     def __init__(self, portId, baudrate=100000):
  16         self._frequency = baudrate
  17         self._spi = _SPI(portId)
  18
  19     # pylint: disable=too-many-arguments,unused-argument
  20     def init(
  21         self,
  22         baudrate=1000000,
  23         polarity=0,
  24         phase=0,
  25         bits=8,
  26         firstbit=_SPI.MSB,
  27     ):
  28         """Initialize the Port"""
  29         self._frequency = baudrate
  30         self._spi.init(
  31             baudrate=baudrate,
  32             polarity=polarity,
  33             phase=phase,
  34             bits=bits,
  35             firstbit=firstbit,
  36             mode=_SPI.MASTER,
  37         )
  38
  39     # pylint: enable=too-many-arguments
  40
  41     @property
  42     def frequency(self):
  43         """Return the current frequency"""
  44         return self._frequency
  45
  46     def write(self, buf, start=0, end=None):
  47         """Write data from the buffer to SPI"""
  48         self._spi.write(buf)
  49
  50     def readinto(self, buf, start=0, end=None, write_value=0):
  51         """Read data from SPI and into the buffer"""
  52         self._spi.readinto(buf)
  53
  54     # pylint: disable=too-many-arguments
  55     def write_readinto(
  56         self, buffer_out, buffer_in, out_start=0, out_end=None, in_start=0, in_end=None
  57     ):
  58         """Perform a half-duplex write from buffer_out and then
  59         read data into buffer_in
  60         """
  61         self._spi.write_readinto(
  62             buffer_out,
  63             buffer_in,
  64             out_start=out_start,
  65             out_end=out_end,
  66             in_start=in_start,
  67             in_end=in_end,
  68         )
  69
  70     # pylint: enable=too-many-arguments