src/adafruit_blinka/microcontroller/nxp_lpc4330/i2c.py

   1 # SPDX-FileCopyrightText: 2021 Melissa LeBlanc-Williams for Adafruit Industries
   2 #
   3 # SPDX-License-Identifier: MIT
   4 """I2C Class for NXP LPC4330"""
   5 from greatfet import GreatFET
   6
   7
   8 class I2C:
   9     """Custom I2C Class for NXP LPC4330"""
  10
  11     # pylint: disable=unused-argument
  12     def __init__(self, *, frequency=100000):
  13         self._gf = GreatFET()
  14
  15     def scan(self):
  16         """Perform an I2C Device Scan"""
  17         return [index for index, dev in enumerate(self._gf.i2c.scan()) if dev[0]]
  18
  19     def writeto(self, address, buffer, *, start=0, end=None, stop=True):
  20         """Write data from the buffer to an address"""
  21         if end is None:
  22             end = len(buffer)
  23         self._gf.i2c.write(address, buffer[start:end])
  24
  25     def readfrom_into(self, address, buffer, *, start=0, end=None, stop=True):
  26         """Read data from an address and into the buffer"""
  27         if end is None:
  28             end = len(buffer)
  29         readin = self._gf.i2c.read(address, end - start)
  30         for i in range(end - start):
  31             buffer[i + start] = readin[i]
  32
  33     # pylint: enable=unused-argument
  34
  35     def writeto_then_readfrom(
  36         self,
  37         address,
  38         buffer_out,
  39         buffer_in,
  40         *,
  41         out_start=0,
  42         out_end=None,
  43         in_start=0,
  44         in_end=None,
  45         stop=False,
  46     ):
  47         """Write data from buffer_out to an address and then
  48         read data from an address and into buffer_in
  49         """
  50         self.writeto(address, buffer_out, start=out_start, end=out_end, stop=stop)
  51         self.readfrom_into(address, buffer_in, start=in_start, end=in_end, stop=stop)