Added typing and missing CP7 functions

[hackapet/Adafruit_Blinka_Displayio.git] / paralleldisplay.py

diff --git a/paralleldisplay.py b/paralleldisplay.py
new file mode 100644 (file)
index 0000000..f2aae8d
--- /dev/null
+++ b/paralleldisplay.py
@@ -0,0 +1,69 @@
+# SPDX-FileCopyrightText: 2020 Melissa LeBlanc-Williams for Adafruit Industries
+#
+# SPDX-License-Identifier: MIT
+
+"""
+`paralleldisplay`
+================================================================================
+
+paralleldisplay for Blinka
+
+**Software and Dependencies:**
+
+* Adafruit Blinka:
+  https://github.com/adafruit/Adafruit_Blinka/releases
+
+* Author(s): Melissa LeBlanc-Williams
+
+"""
+
+import _typing
+import microcontroller
+
+__version__ = "0.0.0-auto.0"
+__repo__ = "https://github.com/adafruit/Adafruit_Blinka_displayio.git"
+
+
+class ParallelBus:
+    """Manage updating a display over 8-bit parallel bus in the background while Python code
+    runs. This protocol may be refered to as 8080-I Series Parallel Interface in datasheets.
+    It doesn't handle display initialization.
+    """
+
+    def __init__(
+        self,
+        *,
+        data0: microcontroller.Pin,
+        command: microcontroller.Pin,
+        chip_select: microcontroller.Pin,
+        write: microcontroller.Pin,
+        read: microcontroller.Pin,
+        reset: microcontroller.Pin,
+        frequency: int = 30000000,
+    ):
+        # pylint: disable=unnecessary-pass
+        """Create a ParallelBus object associated with the given pins. The
+        bus is inferred from data0 by implying the next 7 additional pins on a given GPIO
+        port.
+
+        The parallel bus and pins are then in use by the display until
+        displayio.release_displays() is called even after a reload. (It does this so
+        CircuitPython can use the display after your code is done.) So, the first time you
+        initialize a display bus in code.py you should call
+        :py:func`displayio.release_displays` first, otherwise it will error after the first
+        code.py run.
+        """
+        pass
+
+    def reset(self) -> None:
+        """Performs a hardware reset via the reset pin. Raises an exception if called when
+        no reset pin is available.
+        """
+        raise NotImplementedError("ParallelBus reset has not been implemented yet")
+
+    def send(self, command: int, data: _typing.ReadableBuffer) -> None:
+        """Sends the given command value followed by the full set of data. Display state,
+        such as vertical scroll, set via ``send`` may or may not be reset once the code is
+        done.
+        """
+        raise NotImplementedError("ParallelBus send has not been implemented yet")