Adafruit_CircuitPython_EPD/adafruit_epd/epd.py
2025-05-14 10:08:24 -05:00

428 lines
14 KiB
Python

# SPDX-FileCopyrightText: 2018 Dean Miller for Adafruit Industries
#
# SPDX-License-Identifier: MIT
"""
`adafruit_epd.epd` - Adafruit EPD - ePaper display driver
====================================================================================
CircuitPython driver for Adafruit ePaper display breakouts
* Author(s): Dean Miller
"""
import time
from digitalio import Direction
from micropython import const
from adafruit_epd import mcp_sram
try:
"""Needed for type annotations"""
from typing import Any, Callable, Optional, Union
from busio import SPI
from circuitpython_typing.pil import Image
from digitalio import DigitalInOut
from typing_extensions import Literal
except ImportError:
pass
__version__ = "0.0.0+auto.0"
__repo__ = "https://github.com/adafruit/Adafruit_CircuitPython_EPD.git"
class Adafruit_EPD:
"""Base class for EPD displays"""
BLACK = const(0)
WHITE = const(1)
INVERSE = const(2)
RED = const(3)
DARK = const(4)
LIGHT = const(5)
def __init__(
self,
width: int,
height: int,
spi: SPI,
cs_pin: DigitalInOut,
dc_pin: DigitalInOut,
sramcs_pin: DigitalInOut,
rst_pin: DigitalInOut,
busy_pin: DigitalInOut,
) -> None:
self._width = width
self._height = height
# Setup reset pin, if we have one
self._rst = rst_pin
if rst_pin:
self._rst.direction = Direction.OUTPUT
# Setup busy pin, if we have one
self._busy = busy_pin
if busy_pin:
self._busy.direction = Direction.INPUT
# Setup dc pin (required)
self._dc = dc_pin
self._dc.direction = Direction.OUTPUT
self._dc.value = False
# Setup cs pin (required)
self._cs = cs_pin
self._cs.direction = Direction.OUTPUT
self._cs.value = True
# SPI interface (required)
self.spi_device = spi
while not self.spi_device.try_lock():
time.sleep(0.01)
self.spi_device.configure(baudrate=1000000) # 1 Mhz
self.spi_device.unlock()
self._spibuf = bytearray(1)
self._single_byte_tx = False
self.sram = None
if sramcs_pin:
self.sram = mcp_sram.Adafruit_MCP_SRAM(sramcs_pin, spi)
self._buf = bytearray(3)
self._buffer1_size = self._buffer2_size = 0
self._buffer1 = self._buffer2 = None
self._framebuf1 = self._framebuf2 = None
self._colorframebuf = self._blackframebuf = None
self._black_inverted = self._color_inverted = True
self.hardware_reset()
def display(self) -> None:
"""show the contents of the display buffer"""
self.power_up()
self.set_ram_address(0, 0)
if self.sram:
while not self.spi_device.try_lock():
time.sleep(0.01)
self.sram.cs_pin.value = False
# send read command
self._buf[0] = mcp_sram.Adafruit_MCP_SRAM.SRAM_READ
# send start address
self._buf[1] = 0
self._buf[2] = 0
self.spi_device.write(self._buf, end=3)
self.spi_device.unlock()
# first data byte from SRAM will be transfered in at the
# same time as the EPD command is transferred out
databyte = self.write_ram(0)
while not self.spi_device.try_lock():
time.sleep(0.01)
self._dc.value = True
if self.sram:
for _ in range(self._buffer1_size):
databyte = self._spi_transfer(databyte)
self.sram.cs_pin.value = True
else:
self._spi_transfer(self._buffer1)
self._cs.value = True
self.spi_device.unlock()
time.sleep(0.002)
if self.sram:
while not self.spi_device.try_lock():
time.sleep(0.01)
self.sram.cs_pin.value = False
# send read command
self._buf[0] = mcp_sram.Adafruit_MCP_SRAM.SRAM_READ
# send start address
self._buf[1] = (self._buffer1_size >> 8) & 0xFF
self._buf[2] = self._buffer1_size & 0xFF
self.spi_device.write(self._buf, end=3)
self.spi_device.unlock()
if self._buffer2_size != 0:
# first data byte from SRAM will be transfered in at the
# same time as the EPD command is transferred out
databyte = self.write_ram(1)
while not self.spi_device.try_lock():
time.sleep(0.01)
self._dc.value = True
if self.sram:
for _ in range(self._buffer2_size):
databyte = self._spi_transfer(databyte)
self.sram.cs_pin.value = True
else:
self._spi_transfer(self._buffer2)
self._cs.value = True
self.spi_device.unlock()
elif self.sram:
self.sram.cs_pin.value = True
self.update()
def hardware_reset(self) -> None:
"""If we have a reset pin, do a hardware reset by toggling it"""
if self._rst:
self._rst.value = False
time.sleep(0.1)
self._rst.value = True
time.sleep(0.1)
def command(self, cmd: int, data: Optional[bytearray] = None, end: bool = True) -> int:
"""Send command byte to display."""
self._cs.value = True
self._dc.value = False
self._cs.value = False
while not self.spi_device.try_lock():
time.sleep(0.01)
ret = self._spi_transfer(cmd)
if data is not None:
self._dc.value = True
self._spi_transfer(data)
if end:
self._cs.value = True
self.spi_device.unlock()
return ret
def _spi_transfer(self, data: Union[int, bytearray]) -> Optional[int]:
"""Transfer one byte or bytearray, toggling the cs pin if required by the EPD chipset"""
if isinstance(data, int): # single byte!
self._spibuf[0] = data
# easy & fast case: array and no twiddling
if not self._single_byte_tx and isinstance(data, bytearray):
self.spi_device.write(data)
return None
# if its a single byte
if isinstance(data, int): # single byte!
if self._single_byte_tx:
self._cs.value = False
try:
self.spi_device.write_readinto(self._spibuf, self._spibuf)
except NotImplementedError:
self.spi_device.write(self._spibuf)
if self._single_byte_tx:
self._cs.value = True
return self._spibuf[0]
if isinstance(data, bytearray):
for x in data:
self._spi_transfer(x)
return None
def power_up(self) -> None:
"""Power up the display in preparation for writing RAM and updating.
must be implemented in subclass"""
raise NotImplementedError()
def power_down(self) -> None:
"""Power down the display, must be implemented in subclass"""
raise NotImplementedError()
def update(self) -> None:
"""Update the display from internal memory, must be implemented in subclass"""
raise NotImplementedError()
def write_ram(self, index: int) -> None:
"""Send the one byte command for starting the RAM write process. Returns
the byte read at the same time over SPI. index is the RAM buffer, can be
0 or 1 for tri-color displays. must be implemented in subclass"""
raise NotImplementedError()
def set_ram_address(self, x: int, y: int) -> None:
"""Set the RAM address location, must be implemented in subclass"""
raise NotImplementedError()
def set_black_buffer(self, index: Literal[0, 1], inverted: bool) -> None:
"""Set the index for the black buffer data (0 or 1) and whether its inverted"""
if index == 0:
self._blackframebuf = self._framebuf1
elif index == 1:
self._blackframebuf = self._framebuf2
else:
raise RuntimeError("Buffer index must be 0 or 1")
self._black_inverted = inverted
def set_color_buffer(self, index: Literal[0, 1], inverted: bool) -> None:
"""Set the index for the color buffer data (0 or 1) and whether its inverted"""
if index == 0:
self._colorframebuf = self._framebuf1
elif index == 1:
self._colorframebuf = self._framebuf2
else:
raise RuntimeError("Buffer index must be 0 or 1")
self._color_inverted = inverted
def _color_dup(
self,
func: Callable,
args: Any,
color: Literal[0, 1, 2, 3, 4, 5],
) -> None:
black = getattr(self._blackframebuf, func)
red = getattr(self._colorframebuf, func)
if self._blackframebuf is self._colorframebuf: # monochrome
black(*args, color=(color != Adafruit_EPD.WHITE) != self._black_inverted)
else:
black(*args, color=(color == Adafruit_EPD.BLACK) != self._black_inverted)
red(*args, color=(color == Adafruit_EPD.RED) != self._color_inverted)
def pixel(self, x: int, y: int, color: int) -> None:
"""draw a single pixel in the display buffer"""
self._color_dup("pixel", (x, y), color)
def fill(self, color: int) -> None:
"""fill the screen with the passed color"""
red_fill = ((color == Adafruit_EPD.RED) != self._color_inverted) * 0xFF
black_fill = ((color == Adafruit_EPD.BLACK) != self._black_inverted) * 0xFF
if self.sram:
self.sram.erase(0x00, self._buffer1_size, black_fill)
self.sram.erase(self._buffer1_size, self._buffer2_size, red_fill)
else:
self._blackframebuf.fill(black_fill)
self._colorframebuf.fill(red_fill)
def rect(self, x: int, y: int, width: int, height: int, color: int) -> None:
"""draw a rectangle"""
self._color_dup("rect", (x, y, width, height), color)
def fill_rect(self, x: int, y: int, width: int, height: int, color: int) -> None:
"""fill a rectangle with the passed color"""
self._color_dup("fill_rect", (x, y, width, height), color)
def line(self, x_0: int, y_0: int, x_1: int, y_1: int, color: int) -> None:
"""Draw a line from (x_0, y_0) to (x_1, y_1) in passed color"""
self._color_dup("line", (x_0, y_0, x_1, y_1), color)
def text(
self,
string: str,
x: int,
y: int,
color: int,
*,
font_name: str = "font5x8.bin",
size: int = 1,
) -> None:
"""Write text string at location (x, y) in given color, using font file"""
if self._blackframebuf is self._colorframebuf: # monochrome
self._blackframebuf.text(
string,
x,
y,
font_name=font_name,
size=size,
color=(color != Adafruit_EPD.WHITE) != self._black_inverted,
)
else:
self._blackframebuf.text(
string,
x,
y,
font_name=font_name,
size=size,
color=(color == Adafruit_EPD.BLACK) != self._black_inverted,
)
self._colorframebuf.text(
string,
x,
y,
font_name=font_name,
size=size,
color=(color == Adafruit_EPD.RED) != self._color_inverted,
)
@property
def width(self) -> int:
"""The width of the display, accounting for rotation"""
if self.rotation in {0, 2}:
return self._width
return self._height
@property
def height(self) -> int:
"""The height of the display, accounting for rotation"""
if self.rotation in {0, 2}:
return self._height
return self._width
@property
def rotation(self) -> Literal[0, 1, 2, 3]:
"""The rotation of the display, can be one of (0, 1, 2, 3)"""
return self._framebuf1.rotation
@rotation.setter
def rotation(self, val: int) -> None:
self._framebuf1.rotation = val
if self._framebuf2:
self._framebuf2.rotation = val
def hline(
self,
x: int,
y: int,
width: int,
color: int,
) -> None:
"""draw a horizontal line"""
self.fill_rect(x, y, width, 1, color)
def vline(
self,
x: int,
y: int,
height: int,
color: int,
) -> None:
"""draw a vertical line"""
self.fill_rect(x, y, 1, height, color)
def image(self, image: Image) -> None:
"""Set buffer to value of Python Imaging Library image. The image should
be in RGB mode and a size equal to the display size.
"""
imwidth, imheight = image.size
if imwidth != self.width or imheight != self.height:
raise ValueError(
f"Image must be same dimensions as display ({self.width}x{self.height})."
)
if self.sram:
raise RuntimeError("PIL image is not for use with SRAM assist")
# Grab all the pixels from the image, faster than getpixel.
pix = image.load()
# clear out any display buffers
self.fill(Adafruit_EPD.WHITE)
if image.mode == "RGB": # RGB Mode
for y in range(image.size[1]):
for x in range(image.size[0]):
pixel = pix[x, y]
if (pixel[1] < 0x80 <= pixel[0]) and (pixel[2] < 0x80):
# reddish
self.pixel(x, y, Adafruit_EPD.RED)
elif (pixel[0] < 0x80) and (pixel[1] < 0x80) and (pixel[2] < 0x80):
# dark
self.pixel(x, y, Adafruit_EPD.BLACK)
elif image.mode == "L": # Grayscale
for y in range(image.size[1]):
for x in range(image.size[0]):
pixel = pix[x, y]
if pixel < 0x80:
self.pixel(x, y, Adafruit_EPD.BLACK)
else:
raise ValueError("Image must be in mode RGB or mode L.")