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