
Olimex STM32-H405 Simulator
The industrial-style STM32F405 header board
Simulate the Olimex STM32-H405 header board (STM32F405RG, Cortex-M4 at 168 MHz) in your browser: Arduino C++ through the STM32duino core on QEMU, against the pinout your project will ship on.
Three free 15-minute trial sessions · Then Maker and Pro plans · Runs in your browser
Olimex STM32-H405 at a glance
The STM32-H405 is Olimex's STM32F405RG header board: a Cortex-M4 with FPU at 168 MHz in an industrial-style layout rather than the hobby pill footprint. It runs the same STM32duino core and the same Arduino API surface as the rest of the family; the board is in the catalog so that projects designed around Olimex hardware can be prototyped against the pinout they will actually ship on.
- Processor
- STM32F405RG, Arm Cortex-M4F at 168 MHz
- Memory
- 192 KB SRAM · 1 MB flash
- Emulation
- QEMU (libqemu-arm) on Velxio's servers
- Languages
- Arduino C++ (STM32duino core)
- Made by
- Olimex · Product page
- Plan
- Trial, then Maker or Pro
What you can do with the Olimex STM32-H405 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.
Olimex STM32-H405 examples
Ready-to-run projects for this board from the gallery. Open one, read the sketch, press Run.
Related simulators
Frequently asked questions
- Why simulate the Olimex board instead of a Black Pill?
- For the pinout. The H405 brings the F405's pins out on its own headers, so a project designed for it can be wired here exactly as it will be on the bench.
- Does the STM32F405 differ from the F407 on the Discovery?
- Same core and clock; the F407 adds Ethernet and a camera interface the F405 lacks. On the Arduino API side they behave the same.
- 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 Olimex STM32-H405 simulator free?
- Partly. You can build and save a Olimex STM32-H405 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 Olimex STM32-H405?
- Arduino C++ (STM32duino core). The language is switched from the toolbar; the circuit on the canvas stays the same.
Ready to simulate the Olimex STM32-H405?
Open the editor, place the Olimex STM32-H405 from the picker, wire what you need and press Run.
Launch the Olimex STM32-H405 simulator →