Bill of Materials (BOM)

• Bluepill development board (with a STM32F103C8 MCU)
• Breadboard
• USB C intermediate connector
• LM393P dual comparator
• 3.3kΩ resistors (2pcs)
• 1kΩ resistor
• Wires

Additionally, a device is needed to program the Bluepill. This tutorial assumes you have an ST-Link programmer (or compatible)

Wiring

• On the breadboard, create this schematic (left part only)
• Connect it to the Bluepill board according to the STM32 F1 Family Pin Assignment (Monitor pins only)
• Connect the USB C intermediate connector to the breadboard (GND, CC1 and CC2). Note that CC1 and CC2 might be called A5 and B5.

Software

In the Arduino IDE:

• Install the library "USBPowerDelivery".
• Create a new sketch based on the example "USBPowerDelivery > Protocol Analyzer"
• Compile and upload it to the Bluepill

For more detailed instructions, see https://github.com/manuelbl/usb-pd-arduino/wiki/USB-PD-Protocol-Analyzer-for-5-USD