Discover, configure, and connect to Arduino boards from MATLAB using the Arduino Support Package. Use this skill when the user wants to set up an Arduino board, connect to Arduino hardware, find connected boards, scan serial ports, configure Arduino libraries, or any task that requires an Arduino connection as a prerequisite (e.g., blink LED, read sensor, read digital pin, read analog pin, write pin, plot sensor data, scan I2C, use ultrasonic sensor, control servo, read temperature, read voltage, data logging from hardware). Triggers on: arduino, board setup, COM port, serial port, hardware connection, Arduino Nano, Arduino Uno, Arduino Mega, Arduino Micro, Grove, sensor setup, I2C scan, ultrasonic, servo, readDigitalPin, writeDigitalPin, readVoltage, writePWMVoltage, temperature sensor, air pressure, pin read, pin write, analog input.
Discover, configure, and connect to Arduino boards from MATLAB using the Arduino Support Package. Use this skill when the user wants to set up an Arduino board, connect to Arduino hardware, find connected boards, scan serial ports, configure Arduino libraries, or any task that requires an Arduino connection as a prerequisite (e.g., blink LED, read sensor, read digital pin, read analog pin, write pin, plot sensor data, scan I2C, use ultrasonic sensor, control servo, read temperature, read voltage, data logging from hardware). Triggers on: arduino, board setup, COM port, serial port, hardware connection, Arduino Nano, Arduino Uno, Arduino Mega, Arduino Micro, Grove, sensor setup, I2C scan, ultrasonic, servo, readDigitalPin, writeDigitalPin, readVoltage, writePWMVoltage, temperature sensor, air pressure, pin read, pin write, analog input.
Guides the agent through discovering, configuring, and connecting to Arduino
boards via USB, ensuring the user is informed and in control at each step.
When to Use
User wants to connect to an Arduino board from MATLAB
User asks to discover or list connected Arduino boards
User's task requires an Arduino connection as a prerequisite (reading
sensors, controlling actuators, scanning I2C, etc.)
User mentions Arduino, COM port, serial port, or hardware setup
When NOT to Use
Creating custom addon libraries for unsupported peripherals (see matlab-create-custom-arduino-library)
Bluetooth or WiFi Arduino connections (not covered here)
Arduino IDE or support package installation issues
Simulink hardware-in-the-loop workflows
Tasks that already have an active arduino object in the workspace
Workflow
Follow these steps in order. Do not skip steps or guess values.
Core principle: Never assume. Always ask the user before proceeding
if any information is unclear or ambiguous.
Step 1: Discover boards
Always run both commands — do not skip serialportlist even if
arduinolist already found the board. This is a hard requirement:
list = arduinolist
ports = serialportlist("available")
Both calls are mandatory. Never omit serialportlist — arduinolist
alone misses boards without support package firmware.
arduinolist returns a table with Port, Board, Status, and Libraries
columns. However, it cannot list all connected boards as of R2026a — it
may only show one even when multiple are connected. Always also run
serialportlist("available") to catch all available ports.
If arduinolist is not available (pre-R2024a), skip it and rely on
serialportlist("available") alone.
Present both results to the user.
Step 1b: Handle "no board detected"
If arduinolist returns an empty table AND serialportlist("available")
shows no obvious Arduino ports (or all connection attempts fail), do not
brute-force all ports. Instead:
Ask immediately: "No Arduino board was detected. Is the board
physically connected via USB?"
Guide to OS tools: Present the appropriate guidance to the user
based on their operating system:
Windows: "Open Device Manager → Ports (COM & LPT). Do you see
a device labeled 'Arduino' or 'USB-SERIAL CH340' / 'USB Serial
Device'? If not, the board may not be connected or needs a driver."
macOS: "Run ls /dev/cu.usb* in a terminal. Arduino boards
typically appear as /dev/cu.usbmodem* or /dev/cu.usbserial*."
Linux: "Run dmesg | tail -20 after plugging in the board.
Look for /dev/ttyACM* or /dev/ttyUSB*."
Suggest common fixes:
Try a different USB cable (some are charge-only, no data)
Try a different USB port
Install the board's USB driver (CH340 for clones, FTDI for others)
Ensure no other application (Arduino IDE Serial Monitor, PuTTY)
holds the port open
If the board was manually disconnected without clearing the
arduino object, restart MATLAB and reconnect
STOP and wait. Do not proceed to Step 2 or beyond until the user
responds. If the user confirms the board is not connected, continue
troubleshooting here. If connected, return to Step 1 and re-run
discovery.
Step 2: Help user identify ports
Serial port names alone do not tell the user what device is connected.
Guide the user to identify which ports are Arduino boards:
Windows: "Check Device Manager (Ports section) to see which COM
ports correspond to Arduino boards."
macOS: "Look for /dev/cu.usbmodem* or /dev/cu.usbserial*
entries — these are typically Arduino boards."
Linux: "Check dmesg | grep tty or look for /dev/ttyACM* and
/dev/ttyUSB* devices."
Step 3: Ask the user to select board
Present the discovered boards/ports and ask the user which to connect to.
Never auto-select a board.
Ask for:
Port (required) — which COM port / device path
Board type (optional) — if the user doesn't know, use
arduino('<port>') which auto-detects the board type
For multi-board scenarios, ask the user to identify each board by port
and its intended role.
Step 4: Determine libraries
The default libraries are {'I2C', 'SPI', 'Servo'} — MATLAB loads these
automatically if no Libraries argument is specified.
Library strategy:
Start with the defaults: {'I2C', 'SPI', 'Servo'}
Infer additional libraries from the user's prompt using this mapping:
User mentions
Add library
ultrasonic, distance sensor, HC-SR04
'Ultrasonic'
shift register, 74HC595
'ShiftRegister'
rotary encoder, quadrature
'RotaryEncoder'
motor shield, Adafruit motor
'Adafruit/MotorShieldV2'
motor carrier, MKR motor
'MotorCarrier'
CAN bus
'CAN'
serial device, UART
'Serial'
APDS9960, gesture, color sensor
'APDS9960'
Only infer from the table above when the match is explicit and
unambiguous. If uncertain, ask the user rather than guessing libraries.
Tell the user which libraries you are including and why
Ask the user if any additional libraries are needed
If the user asks what's available, run listArduinoLibraries and
show the full list
Step 5: Connect
Build the arduino() call based on what you gathered:
% TEMPLATE — not executable
% With board type known + custom libraries:
a = arduino('<port>', '<board>', 'Libraries', {'I2C', 'SPI', 'Servo', ...});
% With board type known, default libraries only:
a = arduino('<port>', '<board>');
% Auto-detect board type (uses libraries already flashed on board):
a = arduino('<port>');
Important: You cannot specify 'Libraries' without also specifying the
board type. If the user doesn't know their board type but needs extra
libraries, run arduino('<port>') first to auto-detect, then read
a.Board and reconnect with the board type and libraries specified.
If the connection fails:
Stop immediately — do not retry automatically
Report the exact error message to the user
Provide 1–2 targeted fixes based on the error
Do not retry with different ports or board types unless the user
explicitly instructs
Common issues:
Port is busy (another application has it open)
"Device in use" — an arduino object already exists in the workspace;
the user must clear it before reconnecting
Wrong board type specified
Board needs a firmware reset (double-tap reset button)
Step 6: Confirm and hand off
After successful connection:
Confirm to the user: "Connection established to [Board] on [Port]
with libraries: [list]."
If the user's prompt includes a task beyond just connecting (e.g.,
"blink LED", "read ultrasonic sensor"), announce: "Now proceeding
with [task]..." and continue with the downstream workflow.
Key Functions
Function
Purpose
Available From
arduinolist
Discover connected Arduino boards (table output)
R2024a
serialportlist("available")
List all available serial ports
R2019b
arduino(port)
Connect with auto-detected board type, default libraries
R2014b
arduino(port, board)
Connect with specified board, default libraries
R2014b
arduino(port, board, 'Libraries', libs)
Connect with specified board and custom libraries
R2014b
listArduinoLibraries
List all available add-on libraries
R2014b
Patterns
Single board connection
% TEMPLATE — not executable
% Step 1: Discover
list = arduinolist;
ports = serialportlist("available");
% Step 3-5: Connect (after user selects port and board is known)
a = arduino('COM8', 'Nano33BLE', 'Libraries', {'I2C', 'SPI', 'Servo', 'Ultrasonic'});
Multi-board connection
% TEMPLATE — not executable
% Connect to each board with its own variable and libraries
a1 = arduino('COM8', 'Nano33BLE', 'Libraries', {'I2C', 'SPI', 'Servo'});
a2 = arduino('COM52', 'Uno', 'Libraries', {'I2C', 'SPI', 'Servo', 'Ultrasonic'});
Common Mistakes
Mistake
Why It's Wrong
Correct Approach
Using arduino() with no arguments
Connects to arbitrary board without user consent
Always discover first, let user choose
Guessing COM port or board type
Wastes time on wrong ports, reflashes wrong boards
Ask the user, or use auto-detect with port only
Loading only the needed library
Reconnecting later with more libraries takes 30+ sec
Load defaults {'I2C','SPI','Servo'} plus any inferred extras
Using arduino(port, 'Libraries', libs) without board
Error: must specify both port and board before name-value pairs
Use arduino(port, board, 'Libraries', libs) or arduino(port) for auto-detect with defaults
Skipping serialportlist when arduinolist succeeds
Misses boards without support package firmware or pre-R2024a boards
Always run both — serialportlist is mandatory even when arduinolist returns results
Killing processes to free a port
Destructive action without user consent
Report the port conflict, ask user to close the other application
Conventions
MUST run both arduinolist AND serialportlist("available") in every discovery step — even if arduinolist already found the board. serialportlist catches boards that arduinolist does not recognize.
Always present discovered information to the user before acting
Board type is optional — let MATLAB auto-detect when user doesn't know
Default libraries {'I2C', 'SPI', 'Servo'} are always included
Never take destructive actions (killing processes, clearing workspaces) without asking
Clearly separate the connection step from downstream task execution
Arduino hardware is not shareable — only one MATLAB session can hold a
connection to a given board at a time. Do not run multiple parallel agents
that each try to connect to Arduino hardware. Run Arduino workflows
sequentially.
