Introduction¶

Helpers for getting USB descriptors

Dependencies¶

This driver depends on:

Adafruit CircuitPython 9+

Please ensure all dependencies are available on the CircuitPython filesystem. This is easily achieved by downloading the Adafruit library and driver bundle or individual libraries can be installed using circup.

Installing from PyPI¶

On supported GNU/Linux systems like the Raspberry Pi, you can install the driver locally from PyPI. To install for current user:

pip3 install adafruit-circuitpython-usb-host-descriptors

To install system-wide (this may be required in some cases):

sudo pip3 install adafruit-circuitpython-usb-host-descriptors

To install in a virtual environment in your current project:

mkdir project-name && cd project-name
python3 -m venv .venv
source .env/bin/activate
pip3 install adafruit-circuitpython-usb-host-descriptors

Installing to a Connected CircuitPython Device with Circup¶

Make sure that you have circup installed in your Python environment. Install it with the following command if necessary:

pip3 install circup

With circup installed and your CircuitPython device connected use the following command to install:

circup install adafruit_usb_host_descriptors

Or the following command to update an existing version:

circup update

Usage Example¶

Print basic information about a device and its first (and usually only) configuration.

# SPDX-FileCopyrightText: 2017 Scott Shawcroft, written for Adafruit Industries
# SPDX-FileCopyrightText: Copyright (c) 2023 Scott Shawcroft for Adafruit Industries
#
# SPDX-License-Identifier: Unlicense

import time
import usb.core

import adafruit_usb_host_descriptors

DIR_IN = 0x80

while True:
    print("searching for devices")
    for device in usb.core.find(find_all=True):
        print("pid", hex(device.idProduct))
        print("vid", hex(device.idVendor))
        print("man", device.manufacturer)
        print("product", device.product)
        print("serial", device.serial_number)
        print("config[0]:")
        config_descriptor = adafruit_usb_host_descriptors.get_configuration_descriptor(
            device, 0
        )

        i = 0
        while i < len(config_descriptor):
            descriptor_len = config_descriptor[i]
            descriptor_type = config_descriptor[i + 1]
            if descriptor_type == adafruit_usb_host_descriptors.DESC_CONFIGURATION:
                config_value = config_descriptor[i + 5]
                print(f" value {config_value:d}")
            elif descriptor_type == adafruit_usb_host_descriptors.DESC_INTERFACE:
                interface_number = config_descriptor[i + 2]
                interface_class = config_descriptor[i + 5]
                interface_subclass = config_descriptor[i + 6]
                print(f" interface[{interface_number:d}]")
                print(
                    f"  class {interface_class:02x} subclass {interface_subclass:02x}"
                )
            elif descriptor_type == adafruit_usb_host_descriptors.DESC_ENDPOINT:
                endpoint_address = config_descriptor[i + 2]
                if endpoint_address & DIR_IN:
                    print(f"  IN {endpoint_address:02x}")
                else:
                    print(f"  OUT {endpoint_address:02x}")
            i += descriptor_len
        print()
    time.sleep(5)

Documentation¶

API documentation for this library can be found on Read the Docs.

For information on building library documentation, please check out this guide.

Contributing¶

Contributions are welcome! Please read our Code of Conduct before contributing to help this project stay welcoming.

Table of Contents¶

Examples

Simple test

API Reference