Using the WeAct Blackpill v2.0 as a Source-Level Debug Probe

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Using the WeAct Blackpill v2.0 as a Source-Level Debug Probe

The 1 Bit Squared Blackmagic Debug Probe is a reliable, open-source, source-level debug probe for embedded systems. It supports a huge range of target microcontrollers. In addition to the hardware platform provided by 1 Bit Squared, there are several third-party hardware platforms supported by the firmware repository. One popular choice to host the Blackmagic Firmware is the WeAct Studio’s Blackpill F411CEU6. The Blackmagic Debug repository has detailed instructions for building the Blackmagic Debug Firmware (BMF) and flashing it onto this board.

One issue with using this board as a debug probe is making a reliable connection between it and the target microcontroller. Note in the image above, the debug probe signals are located on a separate set of pins (on the left in the bottom image). Almost all microcontroller development boards use a 2 x 5, 0.05″ pitch connector and flat cable for their debug probe interface. This means to connect the Blackpill debug to the target requires using fly-wires and splicing them to a 10-way IDC cable. Using fly-wires and a spliced cable is far from ideal from both a signal integrity and stability perspective. It is an arrangement that is likely to lead to frustration and misleading results.

To address these shortcomings the Blackpill Debugger Carrier Board was designed.

The Blackpill Debugger Carrier Board is designed to make all the features of BMF available for use from the Blackpill. It has all the status LEDs supported by BMF, together with a connector for connecting a target board UART through USB as a virtual COM port on the host computer. If the target microcontroller uses 3V3 as its power supply, the Carrier Board as a jumper to send the power from the Blackpill.

The Blackpill platform in the BMF repository is a community maintained, fully supported platform, as such, all features such as Single Wire Output (SWO) are available with the Blackpill.

The Blackpill Debugger Carrier is an open-source project, available on GitHub, for those who simply want to get their hands on the Carrier, it is available on Tindie, together with an optional, pre-flashed, Blackpill and optional cable set.