如何在使用Circuit Python时不将Raspberry Pico自动挂载为USB存储

Question

我在Raspberry Pi Pico上使用Circuit Python为我提供了键盘快捷键的硬件按钮。我使用Circuit Python而不是MicroPython，因为它有USB_HID库。

我不希望Pico在插入时自动挂载为USB存储。我只想让它充当HID设备。我知道除了code.py之外，我还可以写一个boot.py脚本，但是我在网上找不到放什么东西会阻止它挂载为code.py设备的地方。我仍然希望它有时作为USB挂载(当按钮被按下/GPIO引脚被连接时)，所以我仍然有一种方法来更改设备上的代码。

这个是可能的吗？而且，如果是这样的话，boot.py应该是什么样子的，只有当某个GPIO引脚连接时才安装？

Answer 1

我最近遇到了一个需要做你正在寻找的同样的事情，在一个像样的兔子洞之后，我决定在这个时候不能这样做。

https://github.com/adafruit/circuitpython/issues/1015

看起来该请求是几年前打开的，并且仍然被列为打开状态。

我不确定在"gadget“模式下运行pi _0是否可以实现这一点，但也许值得一看。

Answer 2

这在CircuitPython学习指南的这一节中有所介绍：https://learn.adafruit.com/circuitpython-essentials/circuitpython-storage

Answer 3

这里有一个很好的HID指南：

https://learn.adafruit.com/circuitpython-essentials/circuitpython-hid-keyboard-and-mouse

下面是HID示例：

import time

import board
import digitalio
import usb_hid
from adafruit_hid.keyboard import Keyboard
from adafruit_hid.keyboard_layout_us import KeyboardLayoutUS
from adafruit_hid.keycode import Keycode

# A simple neat keyboard demo in CircuitPython

# The pins we'll use, each will have an internal pullup
keypress_pins = [board.A1, board.A2]
# Our array of key objects
key_pin_array = []
# The Keycode sent for each button, will be paired with a control key
keys_pressed = [Keycode.A, "Hello World!\n"]
control_key = Keycode.SHIFT

# The keyboard object!
time.sleep(1)  # Sleep for a bit to avoid a race condition on some systems
keyboard = Keyboard(usb_hid.devices)
keyboard_layout = KeyboardLayoutUS(keyboard)  # We're in the US :)

# Make all pin objects inputs with pullups
for pin in keypress_pins:
    key_pin = digitalio.DigitalInOut(pin)
    key_pin.direction = digitalio.Direction.INPUT
    key_pin.pull = digitalio.Pull.UP
    key_pin_array.append(key_pin)

# For most CircuitPython boards:
led = digitalio.DigitalInOut(board.D13)
# For QT Py M0:
# led = digitalio.DigitalInOut(board.SCK)
led.direction = digitalio.Direction.OUTPUT

print("Waiting for key pin...")

while True:
    # Check each pin
    for key_pin in key_pin_array:
        if not key_pin.value:  # Is it grounded?
            i = key_pin_array.index(key_pin)
            print("Pin #%d is grounded." % i)

            # Turn on the red LED
            led.value = True

            while not key_pin.value:
                pass  # Wait for it to be ungrounded!
            # "Type" the Keycode or string
            key = keys_pressed[i]  # Get the corresponding Keycode or string
            if isinstance(key, str):  # If it's a string...
                keyboard_layout.write(key)  # ...Print the string
            else:  # If it's not a string...
                keyboard.press(control_key, key)  # "Press"...
                keyboard.release_all()  # ..."Release"!

            # Turn off the red LED
            led.value = False

    time.sleep(0.01) ```

The example only prints Hello World, so it's not very useful, but it's a good base to mod.