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
Everything in the world has gone insanely USB! USB night lamps, USB flash drives, USB cooling fan, USB mouse, USB keyboard – you name it they got it! They even attached a USB flash drive to the good old Swiss knife. Since everyone wants everything to have USB capability, we need to catch up to the trend and have our embedded projects with USB too.
Tobias Weis shared this easy way to add USB capability to any embedded project. He used his favorite microcontroller – the ATMEGA8 to implement USB communications. The drivers and a matching command line tool are already available for download. The command line tool is used to capture 8 bit binary data from the user which is then interpreted by the ATMEGA8 and now the USB possibilities are endless.
Nokia 3310 LCD are still popular as they are simple to interface and you can find tons of software examples for various microcontrollers. But to push things further there is a nice instructable submitted by wkter. This time display is connected to AVR ATmega8 microcontroller that has software based USB (AVR-USB) that talks to PC.
This way you can easily send various messages or even graphics from any PC with libusb drivers installed. Anyway don’t expect much as USB is pretty slow, but ideal for displaying some information like feeds, tweets or other computer related information. Instructable is greatly explained and has all references needed to push forward.
Could you count how many passwords and usernames you have to remember? All these social networks, bank accounts, emails – it is easy to forget. Writing in paper and keeping them isn’t best idea. So you might need a password managing system that could securely keep track of all your passwords and usernames without worries to loose or forget.
The whole project is built around Atmel AVR ATmega168 microcontroller that is also equipped with LCD display and keypad. The device plugs to PC via USB port that is driven by software. The passwords are stored into Java Card smart card which is considered safe from cracking. The idea of USB interface is to emulate username and password keystrokes so like user would type them physically.