My first attempt using an AVR together with the USB port. It's an HID keyboard device featuring a num lock LED and num lock key. I used the VUSB library that bit bangs the USB by software. The advantage is that any small, cheap AVR like the tiny2313 can be used. This project was published in the June 2013 issue of the Elektor.POST.

Prototype hardware USB stick

This is a prototyping hardware that I use for testing different softwares. Programming is done with micro clips and the dW. It is built into an old USB stick case.

It has an LED attached to a port pin.

All the parts together cost less than �5.

The circuit is simple but needs to fit into a very small case.

The SMD version is very compact. Etched on a blue PCB.

Software 1: USB masterkey

A simple solution to an everyday problem. The stick identifies itself to the PC as keyboard and can hold one or more passwords. The different passwords are activated by typing a short code on the three buttons with LED indicators (num lock, caps lock and scroll lock). If the wrong code is entered or the default combination is wrong the device erases the passwords.

Software 2: Annoyatronic

This software does only one thing: it sets the caps lock button to annoy someone. If the person tries to turn it off it will just go on again after a second. Best place to mount it is on the back of a PC... :-)

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