• https://github.com/gdsports/esp8266-usb-host-demos#
• https://satoshinm.github.io/blog/171227_stm32hid_pill_duck_scriptable_usb_hid_device_using_an_stm32_blue_pill_from_mouse_jigglers_to_rubber_duckies.html# HiD
• http://andybrown.me.uk/2016/01/09/f042usbhid/# McU

• https://randomnerdtutorials.com/raspberry-pi-zero-usb-keyboard-hid/# RpI 0 UsB OtG

• https://github.com/pixjuan/joywheel/blob/master/v1/crankstick/crankstick.ino KeyBoard

• https://groups.google.com/g/nuttx/c/00oWSQ_lVJA/m/9r_5ciOzBQAJ
• https://os.mbed.com/docs/mbed-os/v6.2/apis/usbkeyboard.html# MBeD
• https://os.mbed.com/handbook/USBDevice#

sudo evtest 
No device specified, trying to scan all of /dev/input/event*

• https://github.com/diabolo38/HidKbd# McU StM32 F4
• https://os.mbed.com/questions/5364/Cannot-get-the-Nucleo-F401RE-to-work-as-/# OtG
• https://forums.mbed.com/t/mbed-os-usb-apis-on-thenucleo-f767zi/6934# StM
• https://os.mbed.com/users/mbed_official/code/USBDevice//file/53949e6131f6/USBHID/# MBeD
• https://os.mbed.com/users/va009039/code/F401RE-USBHost/

[214432.960465] usb 1-1.4: new full-speed USB device number 4 using ehci-pci
[214433.054004] usb 1-1.4: New USB device found, idVendor=0d8c, idProduct=013c
[214433.054006] usb 1-1.4: New USB device strings: Mfr=1, Product=2, SerialNumber=0
[214433.054008] usb 1-1.4: Product: USB PnP Sound Device
[214433.054009] usb 1-1.4: Manufacturer: C-Media Electronics Inc.      
[214433.055144] input: C-Media Electronics Inc.       USB PnP Sound Device as /devices/pci0000:00/0000:00:1a.0/usb1/1-1/1-1.4/1-1.4:1.3/0003:0D8C:013C.0003/input/input18
[214433.108624] hid-generic 0003:0D8C:013C.0003: input,hidraw2: USB HID v1.00 Device [C-Media Electronics Inc.       USB PnP Sound Device] on usb-0000:00:1a.0-1.4/input3

 cat /proc/asound/cards
 2 [U0x46d0x8ce    ]: USB-Audio - USB Device 0x46d:0x8ce
                      USB Device 0x46d:0x8ce at usb-0000:00:1d.0-1.3, high speed
 3 [Device         ]: USB-Audio - USB PnP Sound Device
                      C-Media Electronics Inc. USB PnP Sound Device at usb-0000:00:1a.0-1.4, full spe

sudo lsusb
sudo modprobe -rv snd-usb-audio
sudo modprobe -v snd-usb-audio index=-2
cat /proc/asound/cards
alsamixer
sudo alsactl store
aplay /usr/share/sounds/alsa/Noise.wav -D sysdefault:CARD=3

• https://club.dx.com/MyReviews/ReviewDetail/344742A16E134FF297EC8DC76E207188
• http://www.dx.com/p/5-1-channel-usb-sound-card-adapter-black-59039#.V-7agLVodn0# 1.44EUR
• http://karuppuswamy.com/wordpress/2010/10/04/how-to-get-usb-sound-adapter-0d8c000c-working-as-primary-sound-card-in-debian-linux/# AlsA UsB

@TaG: TrackBall UsB