All too many times we end up creating a tool out of necessity. Joonas was looking for a simple way to decode PS/2 keyboard data for another project. So he decided to build a simple logic analyzer that would let him inspect the signals.
The build uses a ATTiny2313 microcontroller, connected to a FTDI USB-to-UART adapter. On the software side it’s real simple, open up a serial port and capture the serial data. The data can then be plotted in OpenSniffer and visualized graphically. One of the downsides to this project is the data rate is pretty low which is estimated at sub 100khz.
Source code is available up at Joonas site.