Hello Bruno,
There is not any USB demo example on FRDM K22F board but there are available USB_LDD demo examples on different boards, see for example
KDS 2.0.0:
KDS_2.0.0\eclipse\ProcessorExpert\Projects\Kinetis\ProcessorExpert\TWR-K70FN1M\USB_MS_Device - this project demonstrates use of USB_LDD component in a device mode as a mass storage device (FLASH DISK).
CW MCU 10.6.x:
CW MCU v10.6\MCU\CodeWarrior_Examples\Processor_Expert\Kinetis\TWR-K21F120M\USB_MS_Device - this project demonstrates use of USB_LDD component in a device mode as a mass storage device (FLASH DISK).
CW MCU v10.6\MCU\CodeWarrior_Examples\Processor_Expert\Kinetis\TWR-K70FN1M\USB_Mass_Storage_Device -this project demonstrates use of USB_LDD component in a device mode as a mass storage device (FLASH DISK).
CW MCU v10.6\MCU\CodeWarrior_Examples\Processor_Expert\Kinetis\TWR-K70FN1M\USB_AudioSpeaker - this project demonstrates use of USB_LDD component in a device mode as a audio speaker device (sound card).
PExDrv V10.4.x
PExDrv v10.4\eclipse\ProcessorExpert\Projects\Kinetis\ProcessorExpert\TWR-K70FN1M\USB_MS_Device - this project demonstrates use of USB_LDD component in a device mode as a mass storage device (FLASH DISK).
Best Regards,
Marek Neuzil