STM32 Black Pill (F401) Simulator
The smaller Black Pill, memory and clock modeled
Simulate the STM32F401CE Black Pill in your browser: the smaller Black Pill, with its own clock ceiling and memory modeled, running Arduino C++ through the STM32duino core on a QEMU Cortex-M4.
Three free 15-minute trial sessions · Then Maker and Pro plans · Runs in your browser
STM32 Black Pill (F401) at a glance
The F401CE is the smaller of the two Black Pills in the catalog: a Cortex-M4 with FPU at 84 MHz, 96 KB of RAM and 512 KB of flash. Everything written for the F411CE applies at the API level; what differs is memory and maximum clock, both modeled here rather than assumed.
- Processor
- STM32F401CE, Arm Cortex-M4F at 84 MHz
- Memory
- 96 KB SRAM · 512 KB flash
- Emulation
- QEMU (libqemu-arm) on Velxio's servers
- Languages
- Arduino C++ (STM32duino core)
- Made by
- STMicroelectronics (STM32F401CE)
- Plan
- Trial, then Maker or Pro
What you can do with the STM32 Black Pill (F401) simulator
The board on the canvas is the real thing as far as your code is concerned: the same pins, the same buses, the same peripherals, wired to the same 100+ sensors, displays and actuators every other Velxio board talks to.
Arduino C++ sketches
Write a sketch in the Monaco editor with library completion, compile it against the board's own Arduino core and run the real firmware binary. The Serial Monitor is the USB port.
GPIO, PWM and ADC
Drive LEDs, relays and servos, read buttons and potentiometers, dim with PWM. Every pin follows the board's real pin map, so what works here works on the hardware.
I2C, SPI and UART
Talk to OLEDs, IMUs, ADCs, RTCs and SD cards over the buses the board really has. Bus traffic runs through emulated peripherals, not through a shortcut.
Serial Monitor
USB CDC serial reaches the Serial Monitor at the sketch's baud rate, with input, timestamps and a plotter.
Multi-board canvas
Mix this board with an Arduino, an ESP32 or a Pico on the same canvas and let them talk over serial or I2C, each running its own firmware.
Try it before you subscribe
A free account gets three 15-minute trial sessions on this board family; every run inside a session is free. Unlimited runs are part of the Maker and Pro plans and of Velxio Desktop.
STM32 Black Pill (F401) examples
Ready-to-run projects for this board from the gallery. Open one, read the sketch, press Run.
Related simulators
Frequently asked questions
- Do Black Pill F411 examples run on the F401?
- Yes. The examples on this page come from the F411 and the Blue Pill; the F401 runs them with the same pin names. A sketch that depends on the 100 MHz clock will run slower, as it would on the hardware.
- What does the STM32 simulator cost?
- The editor is free, and any account can place the board and wire a circuit. Running it boots a QEMU guest on Velxio's servers: a free account gets three 15-minute trial sessions on the STM32 family, and unlimited runs are part of the Maker and Pro plans.
- Is the STM32 Black Pill (F401) simulator free?
- Partly. You can build and save a STM32 Black Pill (F401) circuit with any account, and a free account gets three 15-minute trial sessions to run it; every run inside a session is free. Unlimited runs boot a Linux guest on our servers, so they are part of the Maker and Pro plans, or of Velxio Desktop with a paid licence.
- Which languages can I use on the STM32 Black Pill (F401)?
- Arduino C++ (STM32duino core). The language is switched from the toolbar; the circuit on the canvas stays the same.
Ready to simulate the STM32 Black Pill (F401)?
Open the editor, place the STM32 Black Pill (F401) from the picker, wire what you need and press Run.
Launch the STM32 Black Pill (F401) simulator →