PIC 18F4550 and 18F2550 are powerful microcontrollers including a full-speed USB V2.0 compliant interface. With these MCU it’s very easy for the hobbyist to design USB devices with very few components. In these pages, I’m describing how to use the CDC firmware from Microchip. It permits to emulate a serial port with a PC running Windows or Linux. It’s also very easy to build HID devices.
Build a USB device with a PIC – [Link]