JackKnife is a software system that runs on Arduino hardware (or most any AVR MCU). JackKnife implements a Teletype controller and code converter. As currently configured it’s intended to run on the Arduino Uno but should also run without modification on the Nano and Pro-mini. Going forward, the JackKnife code will be ported to the Microchip ATtiny3216 and AVR128DBxx.

JackKnife was primarily designed to control Baudot (Murray) 5 unit teleprinters, but it can also control a Centronics Parallel printer and a serial thermal receipt printer, as well as a small LCD display. Data sent to the teleprinter can also modulate a Direct Digital Synthesizer (DDS) to generate a low level RF FSK signal.

Primary inputs are AFSK Baudot and USB ASCII serial. Additional inputs are Baudot TTL serial and ASCII TTL serial. There is also a canned message feature that allows the user to send canned messages to the printers. These canned messages are stored in the Arduio’s program memory.

The source code is available on request and is licensed under the the GNU GNU General Public License Version 3 as published by the Free Software Foundation.

Click HERE for a link to a PDF of a set of slides that show the main features of the JackKnife system.

Below are links to a series of videos that describe the JackKnife software system as well as specific configurations.

Overview video of JackKnife Teletype Controller and Signal Processor


JackKnife Teleprinter Controller — AFSK Demodulator Details


JackKnife Teleprinter Controller — USB to TTY Converter Details


JackKnife Teleprinter Controller – LCD Display Details


JackKnife Teleprinter Controller – Direct Digital Synthesizer Details


JackKnife Teleprinter Controller – Alternative Printer Details