🛠 Component inspector
Add a resistor, switch or potentiometer to edit its value.
Default models: resistor 330 Ω, LED forward drop 2.0 V, potentiometer 10 kΩ, switch initially open. Use the inspector to adjust supported values.
Click components on the left
or select “Load Example”
Connect component pins, set component values, and calculate live DC node voltages and branch currents.
No electrical branches yet.
Educational DC nodal-analysis model. It approximates voltage sources with small internal resistance and LEDs with a 2.0 V forward drop plus series resistance. It is not a SPICE solver: inductors, capacitors transients, transistor operating regions, AC, thermal effects and physical breadboard hole-level nets are not solved yet.
Shields now stack directly over the Arduino Uno. Select a stacked board here to configure its simulated functions; header pins are internally mapped to Uno pins.
Place one of the seven shields to enable its controls.
Pin-level wiring is available on the circuit canvas. These are functional educational control models; they do not emulate every internal chip, network protocol stack, motor-driver current limit, relay contact arc, or CNC motion-control safety feature.
Serial.available() and Serial.read() in supported sketches.servoWrite(pin, angle) · 0–180°motorWrite(pinA, pinB, speed)tone(pin, frequency) / noTone(pin)relayWrite(pin, true)Inspect live pin signals, visualize serial numbers, and run guided practical checks without hardware.
Waiting for signal
Plots the latest numeric values printed with Serial.println().
No numeric Serial output yet
Green = HIGH, dark = LOW; PWM channels show duty cycle.
Choose a test and press Start test.
Educational instruments read simulated pin state; they do not model physical voltage noise, circuit faults, AVR timing or real current flow.
Practise placing jumpers on a virtual breadboard, check continuity, and measure simulated Arduino pin voltage.
Click one hole, then another to place a jumper. Red/blue rails run vertically; each numbered terminal row is connected horizontally in groups of five on either side of the centre gap.
Select two holes to add a jumper.
The meter follows simulated pin outputs while your sketch runs.
Choose a challenge to see the target and get feedback.
Training model: breadboard holes have educational row/rail connectivity and jumper paths. This trainer does not yet solve full electrical networks or simulate component current/voltage drops.
Calculate real component values before building a circuit. These calculators are independent of the Arduino sketch runner.
Enter any two values to calculate voltage, current and resistance.
Find a safe approximate series resistor and its power rating.
Estimate frequency and duty cycle for a standard 555 astable circuit.
Calculate the time constant and approximate 63.2% charge time.
Decode a 4-band resistor using the standard colour code.
Calculate the output of two resistors in series.
Calculators use ideal textbook equations. Actual component tolerances, temperature, supply variation, loading and datasheet limits still matter. Check ratings before wiring a real circuit.
Interactive logic gates, a seven-segment display, a virtual 4×4 keypad, binary/hex conversion and an LCD message panel.
These are interactive teaching instruments. The logic gate and display panels are standalone exercises; they are not yet electrically connected to Arduino code or the breadboard netlist.