# Universal Serial Bus > USB, short for Universal Serial Bus, is an industry standard developed in the mid-1990s that defines the cables, connectors and communications protocols used in a bus for connection, communication, and power supply between computers and electronic devices.\[4] It is currently developed by the USB Implementers Forum. [Wikipedia](https://en.wikipedia.org/wiki/USB) * [Intel Edison USB Host](http://pagealh.com/2015/08/09/getting-started-intel-edison-usb-host/) * [Linux Journal Greg Kroah-Hartman Writing a Simple USB Driver](http://www.linuxjournal.com/article/7353?page=0,0) * [Linux Journal Greg Kroah-Hartman How to Write a Linux USB Device Driver](http://www.linuxjournal.com/article/4786) * [Persistent Names](https://github.com/KurtE/Intel-Edison-and-Galileo) * [Persistent Names](http://hintshop.ludvig.co.nz/show/persistent-names-usb-serial-devices/) > Yoctopuce > > > Yoctopuce designs, manufactures and sells USB devices to let your computer sit in the real world, not in the cloud. Our USB modules are tiny, easy to install and easy to drive programmatically. [Homepage](http://www.yoctopuce.com/) ## Kernel Integration ### Kernel Display Message ```bash root@edison:~# dmesg | grep -i usb [ 0.207321] usbcore: registered new interface driver usbfs [ 0.207421] usbcore: registered new interface driver hub [ 0.207628] usbcore: registered new device driver usb [ 0.742079] usbcore: registered new interface driver asix [ 0.742161] usbcore: registered new interface driver cdc_subset [ 0.742291] usbcore: registered new interface driver cdc_ncm [ 0.744743] ehci_hcd: USB 2.0 'Enhanced' Host Controller (EHCI) Driver [ 0.745063] usbcore: registered new interface driver cdc_acm [ 0.745081] cdc_acm: USB Abstract Control Model driver for USB modems and ISDN adapters [ 0.745196] usbcore: registered new interface driver usb-storage [ 0.745383] usbcore: registered new interface driver usbserial [ 0.745454] usbcore: registered new interface driver pl2303 [ 0.745521] usbserial: USB Serial support registered for pl2303 [ 1.666307] usbcore: registered new interface driver usbhid ... ``` ### Kernel Modules ```bash root@edison:~# lsmod Module Size Used by ... usb_f_acm 14335 1 u_serial 18582 6 usb_f_acm g_multi 70924 0 libcomposite 39245 2 usb_f_acm,g_multi ... ``` ## Userspace Interfaces ### Sysfs ```bash root@edison:~# ls -l /sys/bus/usb/drivers/ drwxr-xr-x 2 root root 0 Jan 1 2000 asix drwxr-xr-x 2 root root 0 Jan 1 2000 cdc_acm drwxr-xr-x 2 root root 0 Jan 1 2000 cdc_ncm drwxr-xr-x 2 root root 0 Jan 1 2000 cdc_subset drwxr-xr-x 2 root root 0 Jan 1 2000 hub drwxr-xr-x 2 root root 0 Jan 1 2000 pl2303 drwxr-xr-x 2 root root 0 Jan 1 2000 snd-usb-audio drwxr-xr-x 2 root root 0 Jan 1 2000 usb drwxr-xr-x 2 root root 0 Jan 1 2000 usb-storage drwxr-xr-x 2 root root 0 Jan 1 2000 usbfs drwxr-xr-x 2 root root 0 Jan 1 2000 usbhid drwxr-xr-x 2 root root 0 Jan 1 2000 usbserial drwxr-xr-x 2 root root 0 Mar 21 18:21 uvcvideo root@edison:~# cat /sys/bus/usb/drivers/option/***/bInterface* root@edison:~# cat /proc/bus/usb/devices ``` ## Applications / Libraries > libusb > > > C library that gives applications easy access to USB devices on many different operating systems. [libusb homepage](http://www.libusb.org/) ### Setup #### Opkg ```bash root@edison:~# opkg install libusb-1.0-dev ``` #### Apt-Get ```bash root@edison:~# apt-get install libusb-1.0-dev libudev-dev root@edison:~# apt-get install libtool ``` #### Pip ```bash root@edison:~# pip install pyusb Downloading/unpacking pyusb Downloading PyUSB-1.0.0.tar.gz (52kB): 52kB downloaded Running setup.py egg_info for package pyusb Installing collected packages: pyusb Running setup.py install for pyusb Successfully installed pyusb Cleaning up... root@edison:~# ``` ### Programs #### Lsusb If USB-host is not powered ```bash root@edison:~# lsusb unable to initialize libusb: -99 ``` If USB-host is powered ```bash root@edison:~# lsusb Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub root@edison:~# ls -l /sys/bus/usb/drivers total 0 drwxr-xr-x 2 root root 0 Jan 1 00:01 asix drwxr-xr-x 2 root root 0 Jan 1 00:01 cdc_acm drwxr-xr-x 2 root root 0 Jan 1 00:01 cdc_ncm drwxr-xr-x 2 root root 0 Jan 1 00:01 cdc_subset drwxr-xr-x 2 root root 0 Jan 1 00:01 ftdi_sio drwxr-xr-x 2 root root 0 Jan 1 00:01 hub drwxr-xr-x 2 root root 0 Jan 1 00:01 pl2303 drwxr-xr-x 2 root root 0 Jan 1 00:01 snd-usb-audio drwxr-xr-x 2 root root 0 Jan 1 00:01 usb drwxr-xr-x 2 root root 0 Jan 1 00:01 usbfs drwxr-xr-x 2 root root 0 Jan 1 00:01 usbhid drwxr-xr-x 2 root root 0 Jan 1 00:01 usbserial drwxr-xr-x 2 root root 0 Jan 1 00:01 usb-storage drwxr-xr-x 2 root root 0 Jan 1 00:01 uvcvideo ``` **Libusb Git Repository** ```bash root@edison:~# git clone https://github.com/libusb/libusb.git root@edison:~# cd libusb root@edison:~# ./autogen.sh -disable-udev root@edison:~# make root@edison:~# cd examples root@edison:~# ./listdevs 1d6b:0003 (bus 2, device 1) 0458:708a (bus 1, device 3) path: 1.1 05e3:0606 (bus 1, device 2) path: 1 1d6b:0002 (bus 1, device 1) ``` --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. 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