Have to Unplug / Re-Plug USB Host Keyboard

[FoamyGuy]

CircuitPython version

Adafruit CircuitPython 9.0.0-beta.0 on 2024-01-27; Adafruit Feather RP2040 USB Host with rp2040

Code/REPL

print("hello")

Behavior

I've tested various states of powering on the microcontroller with and without the USB Keyboard plugged in to the host port and found that if the microcontroller powers up with the keyboard plugged in, the keyboard will not work until it has been unplugged and re-plugged.

I tested the following scenarios:

• start with microcontroller unplugged and USB Keyboard unplugged
• plug in the microcontroller to power
• minimal code executes and completes instantly-ish
• plug in the USB Keyboard to the USB Host port
• The keyboard works and is able to press ctrl-C and then start typing into the REPL

• Start with microcontroller unplugged from power, but with the USB Keyboard plugged in to the USB Host port
• plug in the microcontroller to power
• minimal code executes and completes instantly-ish
• The keyboard plugged in to the host port is unresponsive ctrl-C nor any other keys seem to do anything.
• Can restart the MCU multiple times with ctrl-D / ctrl-C from the keyboard plugged in to the PC and connected via tio. Still the keyboard plugged in to USB Host port is unresponsive
• Unplug the keyboard from USB Host port and re-plug it back in
• Now the keyboard plugged in to USB Host port works, ctrl-C and other key presses can be sent to interact with the REPL

Description

No response

Additional information

I noticed that there is a board.USB_HOST_5V_POWER pin defined in this device. I attempted to use digitalio to toggle it off and back on to simulate the unplug / re-plug action but it raised an error about pin in use. I only tested from code.py but will attempt from boot.py later.

If it is possible to toggle that pin and have it serve the same purpose as unplugging and re-plugging then user code would have a way to work around this issue without needing the explicit action from the human user to unplug and re-plug.

[FoamyGuy]

I tried toggling that pin in boot.py as well with this code:

usb_host_power = digitalio.DigitalInOut(board.USB_HOST_5V_POWER)
usb_host_power.direction = digitalio.Direction.OUTPUT
usb_host_power.value = False
time.sleep(0.5)
usb_host_power.value = True

But it still results in the same ValueError: USB_HOST_5V_POWER in use that came from code.py as well.

[jepler]

With #8937 you will be able to use the USB_HOST_5V_POWER pin from code

[tannewt]

@hathach How do we initialize the USB host stuff so that we can see devices that are already attached? Do we need to toggle power or is there a TinyUSB bug here?

[hathach]

@hathach How do we initialize the USB host stuff so that we can see devices that are already attached? Do we need to toggle power or is there a TinyUSB bug here?

when initializing usb host, it should reset controller, any current attached device should go to enumeration process as newly plugged. Otherwise, it is a bug with controller, in this case is the pio-usb controller. Let me try to reproduc this first, @FoamyGuy do you have any quick code.py to test with.

[FoamyGuy]

@hathach during this test I was not using any specific code. I think just the default print("hello world") file that comes from a storage format.

The code itself wasn't trying to interact with the keyboard. I was trying to use the keyboard to interact with the REPL after the code finished executing.

[tannewt]

@hathach CircuitPython 9 will automatically use a connected keyboard as input. This is done by the supervisor using the TinyUSB host HID driver. So, no specific code.py is needed on the RP2040 USB host feather because the board_init() starts up the USB host port.

[hathach]

@jepler I am able to reproduce the issue with my generic low speed usb keyboard. I will try to find an full speed usb to test with as well, just curious if your keyboard is low speed or full speed ? they are handled differently in pio-usb.

[tannewt]

I believe my keyboard is low speed as well.