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Merge pull request #40 from mikeysklar/fpc7519-support
Auto-detect FPC-7519rev.b panel so old and new MagTags work without manual configuration
2 parents 292f58b + d391233 commit f17e62d

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Lines changed: 129 additions & 46 deletions

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‎adafruit_ssd1680.py‎

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"""
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import time
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import digitalio
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from epaperdisplay import EPaperDisplay
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try:
@@ -58,6 +61,101 @@
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_STOP_SEQUENCE = b"\x10\x80\x01\x01\x64" # Deep Sleep
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# LUT for original MagTag panel: FPC-A005 (SSD1680, User ID first byte 0x00)
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FPC_A005_LUT = (
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b"\x2a\x60\x15\x00\x00\x00\x00\x00\x00\x00\x00\x00" # VS L0
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b"\x20\x60\x10\x00\x00\x00\x00\x00\x00\x00\x00\x00" # VS L1
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b"\x28\x60\x14\x00\x00\x00\x00\x00\x00\x00\x00\x00" # VS L2
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b"\x00\x60\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00" # VS L3
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b"\x00\x90\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00" # VS L4
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b"\x00\x02\x00\x05\x14\x00\x00" # TP, SR, RP Group0
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b"\x1e\x1e\x00\x00\x00\x00\x01" # TP, SR, RP Group1
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b"\x00\x02\x00\x05\x14\x00\x00" # TP, SR, RP Group2
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b"\x00\x00\x00\x00\x00\x00\x00" # TP, SR, RP Group3
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b"\x00\x00\x00\x00\x00\x00\x00" # TP, SR, RP Group4
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b"\x00\x00\x00\x00\x00\x00\x00" # TP, SR, RP Group5
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b"\x00\x00\x00\x00\x00\x00\x00" # TP, SR, RP Group6
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b"\x00\x00\x00\x00\x00\x00\x00" # TP, SR, RP Group7
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b"\x00\x00\x00\x00\x00\x00\x00" # TP, SR, RP Group8
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b"\x00\x00\x00\x00\x00\x00\x00" # TP, SR, RP Group9
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b"\x00\x00\x00\x00\x00\x00\x00" # TP, SR, RP Group10
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b"\x00\x00\x00\x00\x00\x00\x00" # TP, SR, RP Group11
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b"\x24\x22\x22\x22\x23\x32\x00\x00\x00" # FR, XON
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)
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# LUT for FPC-7519rev.b and newer panels (User ID first byte != 0x00).
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# GxEPD2_4G (GDEM029T94) waveform with L0/L3 swapped to match CircuitPython's luma mapping
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# (luma 0→L0=black, luma 255→L3=white) and 0x48 flag for DC-balanced drive.
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FPC7519_LUT = (
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b"\x20\x48\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00" # VS L0 (black)
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b"\x08\x48\x10\x00\x00\x00\x00\x00\x00\x00\x00\x00" # VS L1 (dark gray)
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b"\x02\x48\x04\x00\x00\x00\x00\x00\x00\x00\x00\x00" # VS L2 (light gray)
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b"\x40\x48\x80\x00\x00\x00\x00\x00\x00\x00\x00\x00" # VS L3 (white)
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b"\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00" # VS L4 (VCOM)
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b"\x0a\x19\x00\x03\x08\x00\x00" # TP, SR, RP Group0
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b"\x14\x01\x00\x14\x01\x00\x03" # TP, SR, RP Group1
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b"\x0a\x03\x00\x08\x19\x00\x00" # TP, SR, RP Group2
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b"\x01\x00\x00\x00\x00\x00\x01" # TP, SR, RP Group3
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b"\x00\x00\x00\x00\x00\x00\x00" # TP, SR, RP Group4
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b"\x00\x00\x00\x00\x00\x00\x00" # TP, SR, RP Group5
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b"\x00\x00\x00\x00\x00\x00\x00" # TP, SR, RP Group6
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b"\x00\x00\x00\x00\x00\x00\x00" # TP, SR, RP Group7
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b"\x00\x00\x00\x00\x00\x00\x00" # TP, SR, RP Group8
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b"\x00\x00\x00\x00\x00\x00\x00" # TP, SR, RP Group9
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b"\x00\x00\x00\x00\x00\x00\x00" # TP, SR, RP Group10
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b"\x00\x00\x00\x00\x00\x00\x00" # TP, SR, RP Group11
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b"\x22\x22\x22\x22\x22\x22\x00\x00\x00" # FR, XON
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)
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def detect_ssd1680_panel(data_pin, clk_pin, cs_pin, dc_pin, rst_pin):
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"""Read SSD1680 User ID (register 0x2E) via half-duplex bitbang SPI.
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Must be called before the SPI bus is initialized (FourWire claims the pins).
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The SSD1680 responds on the MOSI/DATA line in half-duplex mode, not MISO.
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Returns first byte of User ID:
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0x00 -> FPC-A005 (original/legacy MagTag panel)
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anything else -> FPC-7519rev.b or newer panel; use FPC7519_LUT
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"""
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data = digitalio.DigitalInOut(data_pin)
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clk = digitalio.DigitalInOut(clk_pin)
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cs = digitalio.DigitalInOut(cs_pin)
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dc = digitalio.DigitalInOut(dc_pin)
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rst = digitalio.DigitalInOut(rst_pin)
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for pin in (data, clk, cs, dc, rst):
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pin.direction = digitalio.Direction.OUTPUT
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pin.value = False
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rst.value = False
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time.sleep(0.001)
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rst.value = True
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time.sleep(0.010)
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cmd = 0x2E
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for i in range(8):
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data.value = bool(cmd & (1 << (7 - i)))
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clk.value = True
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clk.value = False
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data.switch_to_input(pull=digitalio.Pull.UP)
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dc.value = True
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result = 0
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for _ in range(8):
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result = (result << 1) | (1 if data.value else 0)
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clk.value = True
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clk.value = False
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cs.value = True
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for pin in (data, clk, cs, dc, rst):
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pin.deinit()
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return result
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# pylint: disable=too-few-public-methods
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class SSD1680(EPaperDisplay):
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r"""SSD1680 driver

‎examples/ssd1680_2.9_grayscale_magtag2025.py‎

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# SPDX-FileCopyrightText: 2026 Mikey Sklar, written for Adafruit Industries
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# SPDX-FileCopyrightText: 2025 Scott Shawcroft, written for Adafruit Industries
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# SPDX-FileCopyrightText: Copyright (c) 2021 Melissa LeBlanc-Williams for Adafruit Industries
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#
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# SPDX-License-Identifier: Unlicense
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"""Simple test script for 2.9" 296x128 display. This example runs it in 2bit grayscale mode."""
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"""Simple test script for 2.9" 296x128 display. This example runs it in 2bit grayscale mode.
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Automatically detects whether the MagTag has the original FPC-A005 panel or the
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newer FPC-7519rev.b panel by reading the SSD1680 User ID register before the SPI
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bus is initialized.
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"""
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import time
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@@ -16,74 +22,53 @@
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1723
displayio.release_displays()
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19-
# This pinout works on a MagTag with the newer screen and may need to be altered for other boards.
20-
spi = busio.SPI(board.EPD_SCK, board.EPD_MOSI) # Uses SCK and MOSI
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epd_cs = board.EPD_CS
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epd_dc = board.EPD_DC
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epd_reset = board.EPD_RESET
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epd_busy = board.EPD_BUSY
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display_bus = FourWire(spi, command=epd_dc, chip_select=epd_cs, reset=epd_reset, baudrate=1000000)
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time.sleep(1)
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ti_290mfgn_gray4_lut_code = (
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b"\x2a\x60\x15\x00\x00\x00\x00\x00\x00\x00\x00\x00" # VS L0
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b"\x20\x60\x10\x00\x00\x00\x00\x00\x00\x00\x00\x00" # VS L1
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b"\x28\x60\x14\x00\x00\x00\x00\x00\x00\x00\x00\x00" # VS L2
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b"\x00\x60\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00" # VS L3
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b"\x00\x90\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00" # VS L4
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b"\x00\x02\x00\x05\x14\x00\x00" # TP, SR, RP of Group0
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b"\x1e\x1e\x00\x00\x00\x00\x01" # TP, SR, RP of Group1
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b"\x00\x02\x00\x05\x14\x00\x00" # TP, SR, RP of Group2
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b"\x00\x00\x00\x00\x00\x00\x00" # TP, SR, RP of Group3
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b"\x00\x00\x00\x00\x00\x00\x00" # TP, SR, RP of Group4
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b"\x00\x00\x00\x00\x00\x00\x00" # TP, SR, RP of Group5
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b"\x00\x00\x00\x00\x00\x00\x00" # TP, SR, RP of Group6
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b"\x00\x00\x00\x00\x00\x00\x00" # TP, SR, RP of Group7
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b"\x00\x00\x00\x00\x00\x00\x00" # TP, SR, RP of Group8
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b"\x00\x00\x00\x00\x00\x00\x00" # TP, SR, RP of Group9
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b"\x00\x00\x00\x00\x00\x00\x00" # TP, SR, RP of Group10
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b"\x00\x00\x00\x00\x00\x00\x00" # TP, SR, RP of Group11
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b"\x24\x22\x22\x22\x23\x32\x00\x00\x00" # FR, XON
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panel_id = adafruit_ssd1680.detect_ssd1680_panel(
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board.EPD_MOSI, board.EPD_SCK, board.EPD_CS, board.EPD_DC, board.EPD_RESET
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)
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print(f"SSD1680 User ID first byte: 0x{panel_id:02x}")
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if panel_id == 0x00:
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print("Detected: FPC-A005 panel (legacy)")
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vcom = 0x28
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colstart = 0
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lut = adafruit_ssd1680.FPC_A005_LUT
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else:
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print("Detected: FPC-7519rev.b or newer panel")
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vcom = 0x24
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colstart = 8
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lut = adafruit_ssd1680.FPC7519_LUT
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spi = busio.SPI(board.EPD_SCK, board.EPD_MOSI)
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display_bus = FourWire(
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spi, command=board.EPD_DC, chip_select=board.EPD_CS, reset=board.EPD_RESET, baudrate=1000000
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)
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time.sleep(1)
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if len(ti_290mfgn_gray4_lut_code) != 153:
51-
raise ValueError("ti_290mfgn_gray4_lut_code is not the correct length")
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# For issues with display not updating top/bottom rows correctly set colstart to 8, 0, or -8
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display = adafruit_ssd1680.SSD1680(
5548
display_bus,
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width=296,
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height=128,
58-
busy_pin=epd_busy,
51+
busy_pin=board.EPD_BUSY,
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rotation=270,
60-
colstart=0,
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vcom=0x28,
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colstart=colstart,
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vcom=vcom,
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vsh2=0xAE,
63-
custom_lut=ti_290mfgn_gray4_lut_code,
56+
custom_lut=lut,
6457
grayscale=True,
6558
)
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6760
g = displayio.Group()
68-
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pic = displayio.OnDiskBitmap("/display-ruler-640x360.bmp")
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t = displayio.TileGrid(pic, pixel_shader=pic.pixel_shader)
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g.append(t)
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display.root_group = g
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display.refresh()
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7768
print("refreshed")
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7970
time.sleep(display.time_to_refresh + 5)
80-
# Always refresh a little longer. It's not a problem to refresh
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# a few seconds more, but it's terrible to refresh too early
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# (the display will throw an exception when if the refresh
83-
# is too soon)
8471
print("waited correct time")
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87-
# Keep the display the same
8873
while True:
8974
time.sleep(10)

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