Spark Logic

BluePill F4 connection guide

BluePill F4 BluepillF405 prototype wiring guide with power, signal assignments, and bench checks.

BluepillF405 prototype

54 contacts Current package

STM32duino community project · The prototype schematic fits STM32F405RGT6 and uses separate 3.3 V digital and analog regulators. Confirm the PCB revision before applying these header numbers.

Power the board from USB

Required

Use a single USB cable to power the board through its native connector. Leave external power headers disconnected. Check the 3.3 V rail before attaching the debug probe.

Bench checks

  • Identify the USB power input and ground in the board schematic.
  • Measure roughly 3.3 V between the board logic rail and ground. Check for a short or wrong connector if the rail is low.

BluepillF405 prototype connector map

Connection scenarios

Connect a 3.3 V UART console

Use an external 3.3 V logic-level adapter and keep the board on USB power. Cross transmit and receive, share ground and match the serial framing. PA10 also connects to the USB ID contact through 1 kΩ. Use a USB device cable that leaves ID floating for this UART setup.

Bench checks

  • Leave the adapter’s supply output disconnected.
  • Enable USART1 on PA9/PA10 and verify that the host receives a known test string.

BluepillF405 prototype connector map

BluepillF405 prototype wiring map

Highlighted contacts are used in the required step or selected circuit. Select a contact to inspect it.

Header · J5
Use the board connector marking and locate contact 1 before wiring.
Header · J6
Use the board connector marking and locate contact 1 before wiring.
SWD header · J1
Use the board connector marking and locate contact 1 before wiring.
USB connector · J2
Use the board connector marking and locate contact 1 before wiring.
Boot header · J3
Use the board connector marking and locate contact 1 before wiring.
Selected pin details

J2-5 · GND

Return · Ground

Connects to the board’s ground plane.

BluepillF405 prototype connector map

Electrical limits · Pin in the reference

Models and documents

The maps follow the listed PCB variants. Match the board markings and connector positions to the referenced schematic before applying power.

BluepillF405 prototype
The prototype schematic fits STM32F405RGT6 and uses separate 3.3 V digital and analog regulators. Confirm the PCB revision before applying these header numbers.