Every one of us, who has worked with AVR or in particular low-cost AVR, has experienced problem while using serial communication. Since, majority of the new laptops, lack a dedicated serial port, users often tend to use a serial to USB converters but suffer from a really hard time. Another option is to use a USB to TTL converter, by using a FTDI chip, but again that is a little costly product. To add USB functionality to low cost AVR, VUSB was discovered. With this, it’s possible to make a very low-cost standalone Arduino with USB port and without having to use an FTDI chip. However by using VUSB, you tend to miss out the serial communication feature.
The author of the project decided to make a HID-class USB device which does not require driver installation. And is compatible with serial communication. For those who don’t know, HID stands for Human Interface Device. It’s a USB class designed primarily for keyboard, mice, joystick, and similar human interface devices. The user implemented the whole design by using variety of software such as Easylogger and some sort of data processing was also implemented. Overall, an excellent project and is compatible with majority of the AVR but only cons that it lacks speed