An open source hardware hacking tool that assists in identifying on-chip debug (OCD) interfaces from test points, vias, component pads, or connectors of an electronic device.
Main project page: https://jtagulator.com
Documentation: https://github.com/grandideastudio/jtagulator/wiki
Videos: YouTube playlist
The JTAGulator firmware is built with the Parallax Propeller Tool version 1.3.2 for Windows. If you wish to compile code or contribute to the project, we recommend using this software. Alternative development environments are untested and unsupported.
Official releases: https://github.com/grandideastudio/jtagulator/tags
Demonstration of the firmware update process: https://www.youtube.com/watch?v=xlXwy-weG1M
Firmware compilation using OpenSpin: openspin -o JTAGulator.eeprom -e -v JTAGulator.spin
Firmware testing using PropLoader (write to RAM): proploader -p /dev/SERIALPORT -v JTAGulator.eeprom
Firmware updating (write to EEPROM): proploader -p /dev/SERIALPORT -v -e JTAGulator.eeprom
Note: This is a development repository. Interim commits may be unstable.
Created by Joe Grand of Grand Idea Studio.
As of July 2025, this project is maintained and supported by EXPLIoT.
Contributions by @samyk, @kbembedded, @BenGardiner, Bryan Angelo, @adamgreen, @0ff, @stephengroat, @alexmaloteaux, HexView, @piggybanks, Crypt, @dummys, and Bob Heinemann.
The JTAGulator design is distributed under a Creative Commons Attribution-ShareAlike 4.0 International license. This means that you can share and adapt the work, but you must attribute the work to the original author and distribute any contributions under this same license.
The JTAGulator name and logo are registered trademarks of Grand Idea Studio. The marks may not be used on derived works without permission.