On-chip debug (OCD) interfaces can provide chip-level control of a target device and are a primary vector used by engineers, researchers, and hackers to extract program code or data, modify memory contents, or affect device operation on-the-fly. Depending on the complexity of the target device, manually locating available OCD connections can be a difficult and time consuming task, sometimes requiring physical destruction or modification of the device.
Designed by Grand Idea Studio, JTAGulator is an open source hardware tool that assists in identifying OCD connections from test points, vias, or component pads on a target device.
24 I/O channels with input protection circuitry
Adjustable target voltage: 1.2 V to 3.3 V
Supported target interfaces (as of firmware v1.1): JTAG/IEEE 1149.1, UART/asynchronous serial
USB interface for direct connection to host computer (PC, Macintosh, or *nix)
Discover on-chip debug interfaces
Simple logic analyzer
Propeller development board
Note: Proper use of this tool requires basic electronics knowledge. To avoid damage to the JTAGulator or target circuitry, please take care to ensure the proper target voltage level is set. Some on-chip debug interfaces may not be detectable if password protection or other security mechanisms are implemented.