# SPDX-FileCopyrightText: 2022 Randall Bohn (dexter)
#
# SPDX-License-Identifier: MIT
"Provides the protocol objects for I2C and SPI"
from busio import I2C, SPI
from digitalio import DigitalInOut
[docs]
class I2C_Impl:
"Protocol implementation for the I2C bus."
def __init__(self, i2c: I2C, address: int) -> None:
from adafruit_bus_device import ( # pylint: disable=import-outside-toplevel
i2c_device,
)
self._i2c = i2c_device.I2CDevice(i2c, address)
[docs]
def read_register(self, register: int, length: int) -> bytearray:
"Read from the device register."
with self._i2c as i2c:
i2c.write(bytes([register & 0xFF]))
result = bytearray(length)
i2c.readinto(result)
return result
[docs]
def write_register_byte(self, register: int, value: int) -> None:
"""Write to the device register"""
with self._i2c as i2c:
i2c.write(bytes([register & 0xFF, value & 0xFF]))
[docs]
class SPI_Impl:
"""Protocol implemenation for the SPI bus."""
def __init__(
self,
spi: SPI,
cs: DigitalInOut,
baudrate: int = 100000,
) -> None:
from adafruit_bus_device import ( # pylint: disable=import-outside-toplevel
spi_device,
)
self._spi = spi_device.SPIDevice(spi, cs, baudrate=baudrate)
[docs]
def read_register(self, register: int, length: int) -> bytearray:
"Read from the device register."
register = (register | 0x80) & 0xFF # Read single, bit 7 high.
with self._spi as spi:
spi.write(bytearray([register])) # pylint: disable=no-member
result = bytearray(length)
spi.readinto(result) # pylint: disable=no-member
# print("$%02X => %s" % (register, [hex(i) for i in result]))
return result
[docs]
def write_register_byte(self, register: int, value: int) -> None:
"Write value to the device register."
register &= 0x7F # Write, bit 7 low.
with self._spi as spi:
spi.write(bytes([register, value & 0xFF])) # pylint: disable=no-member