diff --git a/drivers/epaper/pico_epaper_42_v2_gs.py b/drivers/epaper/pico_epaper_42_v2_gs.py new file mode 100644 index 0000000..ab5a98f --- /dev/null +++ b/drivers/epaper/pico_epaper_42_v2_gs.py @@ -0,0 +1,362 @@ +# Materials used for discovery can be found here +# https://www.waveshare.com/wiki/4.2inch_e-Paper_Module_Manual#Introduction +# Note, at the time of writing this, none of the source materials have working +# code that works with partial refresh, as the C code has a bug and all the other +# materials use that reference material as the source of truth. +# ***************************************************************************** +# * | File : pico_epaper_42_v2_gs.py +# * | Author : michael surdouski +# * | Function : Electronic paper driver (greyscale) +# *---------------- +# * | This version: rev2.2 +# * | Date : 2024-05-22 +# ----------------------------------------------------------------------------- +# Permission is hereby granted, free of charge, to any person obtaining a copy +# of this software and associated documnetation files (the "Software"), to deal +# in the Software without restriction, including without limitation the rights +# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell +# copies of the Software, and to permit persons to whom the Software is +# furished to do so, subject to the following conditions: +# +# The above copyright notice and this permission notice shall be included in +# all copies or substantial portions of the Software. +# +# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR +# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, +# FITNESS OR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE +# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER +# LIABILITY WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, +# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN +# THE SOFTWARE. +# + +from machine import Pin, SPI +import framebuf +import time +import asyncio +from drivers.boolpalette import BoolPalette + + +def asyncio_running(): + try: + _ = asyncio.current_task() + except: + return False + return True + + +# Display resolution +_EPD_WIDTH = const(400) +_BWIDTH = _EPD_WIDTH // 4 +_EPD_HEIGHT = const(300) + +_RST_PIN = const(12) +_DC_PIN = const(8) +_CS_PIN = const(9) +_BUSY_PIN = const(13) + +_WHITE = 0xff # white +_LIGHT_GREY = 0xC0 +_DARK_GREY = 0x80 # gray +_BLACK = 0x00 # Blackest + + +# Pulled from demo code in the waveshare link at the top +_LUT = [ + b"\x01", b"\x0A", b"\x1B", b"\x0F", b"\x03", b"\x01", b"\x01", + b"\x05", b"\x0A", b"\x01", b"\x0A", b"\x01", b"\x01", b"\x01", + b"\x05", b"\x08", b"\x03", b"\x02", b"\x04", b"\x01", b"\x01", + b"\x01", b"\x04", b"\x04", b"\x02", b"\x00", b"\x01", b"\x01", + b"\x01", b"\x00", b"\x00", b"\x00", b"\x00", b"\x01", b"\x01", + b"\x01", b"\x00", b"\x00", b"\x00", b"\x00", b"\x01", b"\x01", + b"\x01", b"\x0A", b"\x1B", b"\x0F", b"\x03", b"\x01", b"\x01", + b"\x05", b"\x4A", b"\x01", b"\x8A", b"\x01", b"\x01", b"\x01", + b"\x05", b"\x48", b"\x03", b"\x82", b"\x84", b"\x01", b"\x01", + b"\x01", b"\x84", b"\x84", b"\x82", b"\x00", b"\x01", b"\x01", + b"\x01", b"\x00", b"\x00", b"\x00", b"\x00", b"\x01", b"\x01", + b"\x01", b"\x00", b"\x00", b"\x00", b"\x00", b"\x01", b"\x01", + b"\x01", b"\x0A", b"\x1B", b"\x8F", b"\x03", b"\x01", b"\x01", + b"\x05", b"\x4A", b"\x01", b"\x8A", b"\x01", b"\x01", b"\x01", + b"\x05", b"\x48", b"\x83", b"\x82", b"\x04", b"\x01", b"\x01", + b"\x01", b"\x04", b"\x04", b"\x02", b"\x00", b"\x01", b"\x01", + b"\x01", b"\x00", b"\x00", b"\x00", b"\x00", b"\x01", b"\x01", + b"\x01", b"\x00", b"\x00", b"\x00", b"\x00", b"\x01", b"\x01", + b"\x01", b"\x8A", b"\x1B", b"\x8F", b"\x03", b"\x01", b"\x01", + b"\x05", b"\x4A", b"\x01", b"\x8A", b"\x01", b"\x01", b"\x01", + b"\x05", b"\x48", b"\x83", b"\x02", b"\x04", b"\x01", b"\x01", + b"\x01", b"\x04", b"\x04", b"\x02", b"\x00", b"\x01", b"\x01", + b"\x01", b"\x00", b"\x00", b"\x00", b"\x00", b"\x01", b"\x01", + b"\x01", b"\x00", b"\x00", b"\x00", b"\x00", b"\x01", b"\x01", + b"\x01", b"\x8A", b"\x9B", b"\x8F", b"\x03", b"\x01", b"\x01", + b"\x05", b"\x4A", b"\x01", b"\x8A", b"\x01", b"\x01", b"\x01", + b"\x05", b"\x48", b"\x03", b"\x42", b"\x04", b"\x01", b"\x01", + b"\x01", b"\x04", b"\x04", b"\x42", b"\x00", b"\x01", b"\x01", + b"\x01", b"\x00", b"\x00", b"\x00", b"\x00", b"\x01", b"\x01", + b"\x01", b"\x00", b"\x00", b"\x00", b"\x00", b"\x01", b"\x01", + b"\x00", b"\x00", b"\x00", b"\x00", b"\x00", b"\x00", b"\x00", + b"\x00", b"\x00", b"\x00", b"\x00", b"\x00", b"\x00", b"\x00", + b"\x02", b"\x00", b"\x00", b"\x07", b"\x17", b"\x41", b"\xA8", + b"\x32", b"\x30" +] + + +# Framebuf mapping is pixel 0 is in LS 2 bits +@micropython.viper +def _lmap(dest: ptr8, source: ptr8, pattern: int, length: int): + d: int = 0 # dest index + s: int = 0 # Source index + e: int = 0 # Current output byte (8 pixels of 1 bit) + t: int = 0 # Current input byte (4 pixels of 2 bits) + while d < length: # For each byte of o/p + e = 0 + # Two sets of 4 pixels + for _ in range(2): + t = source[s] + for _ in range(4): + e |= (pattern >> (t & 3)) & 1 + t >>= 2 + e <<= 1 + s += 1 + dest[d] = e >> 1 + d += 1 + + +class EPD(framebuf.FrameBuffer): + MAXBLOCK = 25 # Max async blocking time in ms + # A monochrome approach should be used for coding this. The rgb method ensures + # nothing breaks if users specify colors. + @staticmethod + def rgb(r, g, b): + return min((r + g + b) >> 7, 3) # Greyscale in range 0 <= gs <= 3 + + def __init__(self, spi=None, cs=None, dc=None, rst=None, busy=None): + self._rst = Pin(_RST_PIN, Pin.OUT) if rst is None else rst + self._busy_pin = Pin(_BUSY_PIN, Pin.IN, Pin.PULL_UP) if busy is None else busy + self._cs = Pin(_CS_PIN, Pin.OUT) if cs is None else cs + self._dc = Pin(_DC_PIN, Pin.OUT) if dc is None else dc + self._spi = ( + SPI(1, sck=Pin(10), mosi=Pin(11), miso=Pin(28)) if spi is None else spi + ) + self._spi.init(baudrate=4_000_000) + # Busy flag: set immediately on .show(). Cleared when busy pin is logically false. + self._busy = False + # Async API + self.updated = asyncio.Event() + self.complete = asyncio.Event() + + # Public bound variables required by nanogui. + # Dimensions in pixels as seen by nanogui + self.width = _EPD_WIDTH + self.height = _EPD_HEIGHT + # Other public bound variable. + # Special mode enables demos written for generic displays to run. + self.demo_mode = False + + self._buf = bytearray(_EPD_HEIGHT * _BWIDTH) + self._mvb = memoryview(self._buf) + self._ibuf = bytearray(1000) # Buffer for inverted pixels + # Patterns for the two hardware buffers. + # LS 4 bits are o/p colors for white, grey1, grey2, black + self._patterns = (0b0101, 0b0011) + mode = framebuf.GS2_HMSB + self.palette = BoolPalette(mode) # Enable CWriter. + super().__init__(self._buf, _EPD_WIDTH, _EPD_HEIGHT, mode) + self.init() + time.sleep_ms(500) + + # Hardware reset + def reset(self): + for v in (1, 0, 1): + self._rst(v) + time.sleep_ms(20) + + def _command(self, command, data=None): + self._dc(0) + self._cs(0) + self._spi.write(command) + self._cs(1) + if data is not None: + self._data(data) + + def _data(self, data): + self._dc(1) + self._cs(0) + self._spi.write(data) + self._cs(1) + + def display_on(self): + self._command(b"\x22") + self._data(b"\xCF") + self._command(b"\x20") + + def init(self): + self.reset() # hardware reset + self.wait_until_ready() + + self._command(b"\x12") # software reset + self.wait_until_ready() + + self._command(b"\x21") # Display update control + self._data(b"\x00") + self._data(b"\x00") + + self._command(b"\x3C") # BorderWaveform + self._data(b"\x03") + + self._command(b"\x11") # data entry mode + self._data(b"\x03") # X-mode + + self._command(b"\x0C") # Boost soft start + self._data(b"\x8B") + self._data(b"\x9C") + self._data(b"\xA4") + self._data(b"\x0F") + + self.set_grey() + + self._set_window() + self._set_cursor() + + self.wait_until_ready() + + def set_grey(self): + self._command(b"\x32") + for i in range(0, 227): + self._data(_LUT[i]) + + self._command(b"\x3F") + self._data(_LUT[227]) + + self._command(b"\x03") + self._data(_LUT[228]) + + self._command(b"\x04") + self._data(_LUT[229]) + self._data(_LUT[230]) + self._data(_LUT[231]) + + self._command(b"\x2C") + self._data(_LUT[232]) + + def wait_until_ready(self): + while not self.ready(): + time.sleep_ms(100) + + def set_partial(self): + pass + + def set_full(self): + pass + + def ready(self): + return not (self._busy or self._busy_pin()) # 1 == busy + + @micropython.native + def _bsend(self, start, pattern, nbytes): # Invert b<->w, buffer and send nbytes source bytes + buf = self._ibuf # Invert and buffer is done 32 bits at a time, hence >> 2 + _lmap(buf, self._mvb[start:], pattern, nbytes) # Invert image data for EPD + self._dc(1) + self._cs(0) + self._spi.write(buf) + self._cs(1) + + def _send_bytes(self, idx): + asyn = asyncio_running() + for _idx, pattern in enumerate(self._patterns): + if _idx != idx: + continue + fbidx = 0 # Index into framebuf + nbytes = len(self._ibuf) # Bytes to send + didx = nbytes * 2 # Increment of framebuf index + nleft = len(self._buf) # Size of framebuf + def inner(): + nonlocal fbidx + nonlocal nbytes + nonlocal nleft + nonlocal didx + ts = time.ticks_ms() # Time of last yield + while nleft > 0: + self._bsend(fbidx, pattern, nbytes) # Grey-map, buffer and send nbytes + fbidx += didx # Adjust for bytes already sent + nleft -= didx + nbytes = min(nbytes, nleft) + if asyn and time.ticks_diff(time.ticks_ms(), ts) > EPD.MAXBLOCK: + return nbytes # Probably not all done; quit and call again + return 0 # All done + return inner + + async def _as_show(self): + self._command(b"\x24") + sb = self._send_bytes(0) # Instantiate closure + while sb(): + await asyncio.sleep_ms(0) + + self._command(b"\x26") + sb = self._send_bytes(1) # Instantiate closure + while sb(): + await asyncio.sleep_ms(0) + + self.updated.set() + self.display_on() + while self._busy_pin(): + await asyncio.sleep_ms(0) + self._busy = False + self.complete.set() + + # Specific method for micro-gui. Unsuitable EPD's lack this method. Micro-gui + # does not test for asyncio as this is guaranteed to be up. + async def do_refresh(self, split=0): + assert not self._busy, "Refresh while busy" + await self._as_show() + + def show(self): + if self._busy: + raise RuntimeError("Cannot refresh: display is busy.") + self._busy = True # Immediate busy flag. Pin goes low much later. + if asyncio_running(): + self.updated.clear() + self.complete.clear() + asyncio.create_task(self._as_show()) + return + + self._command(b"\x24") + sb = self._send_bytes(0) # Instantiate closure + sb() + self._command(b"\x26") + sb = self._send_bytes(1) # Instantiate closure + sb() + self._busy = False + + self.display_on() + + if not self.demo_mode: + # Immediate return to avoid blocking the whole application. + # User should wait for ready before calling refresh() + return + + self.wait_until_ready() + time.sleep_ms(2000) # Demo mode: give time for user to see result + + def sleep(self): + self._command(b"\x10") # deep sleep + self._data(b"\x01") + + # window and cursor always the same for 4.2" + def _set_window(self): + self._command(b"\x44") + self._data(b"\x00") + self._data(b"\x31") + + self._command(b"\x45") + self._data(b"\x00") + self._data(b"\x00") + self._data(b"\x2B") + self._data(b"\x01") + + def _set_cursor(self): + self._command(b"\x4E") + self._data(b"\x00") + + self._command(b"\x4F") + self._data(b"\x00") + self._data(b"\x00")