Blue Pill connection guide
Blue Pill STM32F103C8T6 Blue Pill wiring guide with power, signal assignments, and bench checks.
STM32F103C8T6 Blue Pill
49 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 (H4-1)
- USB return
- USB host ground
- GND (H4-5)
- Board logic rail
- 3V3 (H3-1)
- 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.
STM32F103C8T6 Blue Pill connector map
Connection scenarios
Attach an SWD probe
Use the USB supply from the required step. Configure the probe for a powered 3.3 V target. Connect the probe’s reference input to the board logic rail, then wire SWDIO, SWCLK and ground.
- Target reference
- 3V3 (H3-1)
- Probe VTref input
- Ground
- GND (H3-4)
- Probe ground
- SWD data
- DIO (H3-2)
- Probe SWDIO
- SWD clock
- CLK (H3-3)
- Probe SWCLK
Bench checks
- Check pin 1 orientation and verify each connection with the cable unplugged.
- Select the exact MCU and use a low SWD clock for the first connection.
STM32F103C8T6 Blue Pill connector map
STM32F103C8T6 Blue Pill wiring map
Header 1
Header 2
SWD header
USB connector
H2-1 · 3.3
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.
- STM32F103C8T6 Blue Pill
- The documented blue PCB has two 20-contact headers, SWD and Micro USB. Its PC13 user LED is active low. The USB D+ pull-up varies across production boards.
- STM32-base · STM32F103C8T6 Blue Pill· Board identification, connector numbering and documented net destinations.
- STMicroelectronics MCU datasheet· MCU electrical specifications and package pin functions.
- STM32F103C8T6 Blue Pill schematic· PCB power, debug, connector and peripheral wiring.
