src/adafruit_blinka/microcontroller/nxp_lpc4330/i2c.py

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