1 files changed, 84 insertions, 0 deletions
diff --git a/src/pico/adafruit_register/i2c_bit.py b/src/pico/adafruit_register/i2c_bit.py
new file mode 100755
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+++ b/src/pico/adafruit_register/i2c_bit.py
@@ -0,0 +1,84 @@
+# SPDX-FileCopyrightText: 2016 Scott Shawcroft for Adafruit Industries
+#
+# SPDX-License-Identifier: MIT
+# pylint: disable=too-few-public-methods
+
+"""
+`adafruit_register.i2c_bit`
+====================================================
+
+Single bit registers
+
+* Author(s): Scott Shawcroft
+"""
+
+__version__ = "0.0.0+auto.0"
+__repo__ = "https://github.com/adafruit/Adafruit_CircuitPython_Register.git"
+
+try:
+    from typing import Optional, Type, NoReturn
+    from circuitpython_typing.device_drivers import I2CDeviceDriver
+except ImportError:
+    pass
+
+
+class RWBit:
+    """
+    Single bit register that is readable and writeable.
+
+    Values are `bool`
+
+    :param int register_address: The register address to read the bit from
+    :param int bit: The bit index within the byte at ``register_address``
+    :param int register_width: The number of bytes in the register. Defaults to 1.
+    :param bool lsb_first: Is the first byte we read from I2C the LSB? Defaults to true
+
+    """
+
+    def __init__(
+        self,
+        register_address: int,
+        bit: int,
+        register_width: int = 1,
+        lsb_first: bool = True,
+    ) -> None:
+        self.bit_mask = 1 << (bit % 8)  # the bitmask *within* the byte!
+        self.buffer = bytearray(1 + register_width)
+        self.buffer[0] = register_address
+        if lsb_first:
+            self.byte = bit // 8 + 1  # the byte number within the buffer
+        else:
+            self.byte = register_width - (bit // 8)  # the byte number within the buffer
+
+    def __get__(
+        self,
+        obj: Optional[I2CDeviceDriver],
+        objtype: Optional[Type[I2CDeviceDriver]] = None,
+    ) -> bool:
+        with obj.i2c_device as i2c:
+            i2c.write_then_readinto(self.buffer, self.buffer, out_end=1, in_start=1)
+        return bool(self.buffer[self.byte] & self.bit_mask)
+
+    def __set__(self, obj: I2CDeviceDriver, value: bool) -> None:
+        with obj.i2c_device as i2c:
+            i2c.write_then_readinto(self.buffer, self.buffer, out_end=1, in_start=1)
+            if value:
+                self.buffer[self.byte] |= self.bit_mask
+            else:
+                self.buffer[self.byte] &= ~self.bit_mask
+            i2c.write(self.buffer)
+
+
+class ROBit(RWBit):
+    """Single bit register that is read only. Subclass of `RWBit`.
+
+    Values are `bool`
+
+    :param int register_address: The register address to read the bit from
+    :param type bit: The bit index within the byte at ``register_address``
+    :param int register_width: The number of bytes in the register. Defaults to 1.
+
+    """
+
+    def __set__(self, obj: I2CDeviceDriver, value: bool) -> NoReturn:
+        raise AttributeError()