1  # SPDX-FileCopyrightText: 2017 Scott Shawcroft, written for Adafruit Industries
 2  # SPDX-FileCopyrightText: Copyright (c) 2021 Jeff Epler for Adafruit Industries
 3  #
 4  # SPDX-License-Identifier: Unlicense
 5  """Use this file as CIRCUITPY/boot.py in conjunction with ov2640_jpeg_kaluga1_3.py
 6  
 7  It makes the CIRCUITPY filesystem writable to CircuitPython
 8  (and read-only to the PC) unless the "MODE" button on the audio
 9  daughterboard is held while the board is powered on or reset.
10  """
11  
12  import analogio
13  import board
14  import storage
15  
16  V_MODE = 1.98
17  V_RECORD = 2.41
18  
19  a = analogio.AnalogIn(board.IO6)
20  a_voltage = a.value * a.reference_voltage / 65535  # pylint: disable=no-member
21  if abs(a_voltage - V_MODE) > 0.05:  # If mode is NOT pressed...
22      print("storage writable by CircuitPython")
23      storage.remount("/", readonly=False)