BluePill F4 connection guide
BluePill F4 BluepillF405 prototype wiring guide with power, signal assignments, and bench checks.
BluepillF405 prototype
54 contacts Current packagePower the board from USB
RequiredUse 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.
- USB power input
- USB host VBUS
- VBUS (J2-1)
- USB return
- USB host ground
- GND (J2-5)
- Board logic rail
- VCC3V3 (J1-4)
- 3.3 V measurement point
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.
- Board transmit
- PA9 (J6-15)
- Adapter RX
- Board receive
- PA10 (J6-14)
- Adapter TX
- Ground
- GND (J1-1)
- Adapter GND
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
Boot header · J3
J1-4 · VCC3V3
Connects to 3V3. Use the specified board power connection.
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.
- STMicroelectronics MCU datasheet· MCU electrical specifications and package pin functions.
- BluepillF405 prototype schematic· PCB power, debug, connector and peripheral wiring.
- Original BluePill F4 development thread· Prototype revisions and the reported reset-switch wiring issue.
