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Quickstart

From an account to your firmware running on a twin. You need a firmware ELF built for one of the boards in the catalog; no hardware.

1. Get an account

Sign in with your email address. We send you a 6-digit code; enter it and you are in. The Free plan costs nothing.

CircuitTwin is available in the United States only. The first time you sign in, the app asks where you are located.

2. Run firmware in the browser

The fastest start: on Projects, choose Try a development board. It runs a Blink program on a NUCLEO-F767ZI, STM32F4-Discovery or NUCLEO-F103RB twin and shows the console live.

To run your own firmware:

  1. Make a project with New project, then add a system with New system and pick its microcontroller. A system with one microcontroller is what you would call a board.
  2. Open Runs, choose New run, pick the system and upload the ELF, HEX or BIN you would flash.
  3. Set what counts as a pass, for example a line the console must print, and choose Start run.

The run page shows the console as it runs, then the verdict, each check and any issue the twins found.

3. Install the CLI and sign in

macOS and Linux
curl -fsSL https://circuittwindownloads.blob.core.windows.net/cli/install.sh | sh
ct --version
Windows (PowerShell)
.install.ps1    # in the folder you unpacked
ct --version

Every ct command except ct login needs a signed-in account. Create an access token in the app under Settings, Access tokens (see Access tokens), then:

terminal
ct login --server https://app.circuittwin.ai
# paste the token when asked; ct checks it with the server before storing it
ct login --status

4. Run firmware from your terminal

Run one image on a built-in board until a line appears on the console:

terminal
ct run --board nucleo-f767zi build/app.elf --until "READY"

Exit code 0 means the run reached its target (or ended within its budget without a fault), 1 that it did not, 4 that it completed on peripherals the twin does not model, so it is not a pass. Add sensors on a bus with --device, for example --device INA226@I2C1:0x40, and feed them a scripted world with --scenario.

5. Generate a twin from documents

If your part is not in the catalog, generate it from the vendor’s documents, in the app on the Datasheets page or with ct twin generate. Companion documents (reference manual, errata, vendor headers) make the twin more complete. A new twin uses one generation credit; a part already in the catalog is reused for free.

terminal
ct twin generate stm32f767zi-datasheet.pdf --with rm0410.pdf --output twins/

6. Turn the run into a test

A suite names the board, the firmware and what must happen. Run it locally first, then from your CI:

suite.yaml
schemaVersion: ct.test-suite/1
id: firmware-smoke
name: Firmware smoke test
defaults:
  board:
    id: nucleo-f767zi
cases:
  - id: boots
    name: Firmware boots and reports ready
    firmware:
      path: build/app.elf
    assertions:
      - kind: marker
        pass: READY
      - kind: no_fault
terminal
ct test run suite.yaml --junit report.xml

Next steps