To use this library you need an additional ATMega328P to act as a video processor, and a 74HCT166 shift register to generate the video bit stream. The video processor hex file needs to be programmed into an ATMega328P with the following fuses set: E6 D9 FF In avrdude that is: (change the com port as appropriate) avrdude -P COM3 -b 19200 -c avrisp -p m328p -n avrdude -P COM3 -b 19200 -c avrisp -p m328p -U lfuse:w:0xe6:m avrdude -P COM3 -b 19200 -c avrisp -p m328p -U hfuse:w:0xd9:m avrdude -P COM3 -b 19200 -c avrisp -p m328p -U efuse:w:0xff:m avrdude -P COM3 -b 19200 -c avrisp -p m328p -U flash:w:SBCVideo.hex The video processor code is written by Grant Searle, based on code by Daryl Rictor. Their pages are as follows: http://searle.x10host.com/MonitorKeyboard/index.html http://sbc.rictor.org/vid3.html 80x25 Terminal library by Dave Curran, based on code from the above. For more info see: http://blog.tynemouthsoftware.co.uk/2013/09/arduino-80x25-tv-video-output-library.html http://blog.tynemouthsoftware.co.uk/2013/09/arduino-80x25-tv-video-output-library_15.html