The Rusty Probe

This is an open hardware probe for the Serial Wire Debug (SWD) and JTAG protocol. Based on the RP2040 MCU.

Firmware

The firmware is available here and is open-source.

The 10-pin Cortex-Debug connector is used.
The programming connector is the Tag Connect TC2030, however for just loading firmware the USB bootloader is recommended.
Castellated vias for all programming pins, power and 2 GPIOs.
USB-C connector.
Target 5V and Vtarget is protected with an diode circuit to not have current flow from the target to the host.
The probe support 1.8v - 3.3v signal voltage and can track Vtarget.
The key pin on the Cortex-Debug can be connected to the protected 5V.

The schematic can be found in the GitHub actions, full production files are generated for each commit.

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Here is a small comparison with a few different probes:

	Rusty Probe	PicoProbe	Raspberry Pi Debug Probe	STLinkV3	JLink
Max speed	62 MHz	?	10 MHz	24 MHz	15 MHz
Target support	any	any	any	STM32	any
IO voltage control	1.8-3.3V	3.3V	3.3V	1.6-3.3V	1.6-3.3V somtimes
Type	Open Source & Hardware	Open Source	Proprietary	Proprietary	Proprietary
Language	Rust	C	C	C	C
Protocol	CMSIS-DAP	CMSIS-DAP	CMSIS-DAP	Proprietary	CMSIS-DAP
Programming connector	Cortex-M Debug 10p	-	JST	Cortex-M Debug 14p	Cortex-M Debug 10p
USB speed	12 MBit/s	12 MBit/s	12 MBit/s	480 MBit/s	12 MBit/s

The probe is available in the probe-rs shop. But you are free to build one yourself as well!

This work is licensed under CERN-OHL-P.