IRR BlocksIoT & Robotics Rwanda
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Smart Irrigation

An agricultural monitoring circuit evaluating dual conditions: reservoir fullness (≥ 20%) AND ambient temperature (> 30°C). The Green LED indicates irrigation demand only when both criteria are met.

Smart Irrigation

Objectives

  • Wire a potentiometer on A0 for reservoir level and an MCP9808 on I2C for temperature.
  • Wire a 330 Ω resistor and Green indicator LED to digital pin D13.
  • Program dual logic: turn LED ON only when water fullness is ≥ 20% AND temperature is > 30°C.

Expected behavior

The Green LED turns ON only when reservoir fullness is at least 20% AND temperature exceeds 30°C. Otherwise it remains OFF.

What this simulation can and cannot show

Agricultural teaching model: the LED is a logic status indicator, NOT an electrical pump, high-current solenoid valve, or motor. Real irrigation demands relay isolation and soil sensors. No physical irrigation claim.

Choose how to start

Start blank to place every part yourself, or load the starter: board, breadboard, resistor, LED and an unbound blink program. You still insert parts, make each connection and bind the blocks.

Build steps

0 / 10 steps complete

  1. Place UNO R3 (Not yet)

    Provides 5V, GND, A0, I2C and D13.

  2. Place breadboard (Not yet)

    Houses the potentiometer and indicator LED.

  3. Insert 330 Ω resistor (Not yet)

    Protects the Green indicator LED.

  4. Insert Green LED (Not yet)

    Place the Green demand indicator LED in the breadboard.

  5. Wire potentiometer to A0 (Not yet)

    Connect potentiometer to 5V, GND, and wiper to pin A0.

  6. Wire MCP9808 to I2C (Not yet)

    Connect MCP9808 VIN to 5V, GND to GND, SCL to SCL, SDA to SDA.

  7. Wire D13 to LED and GND (Not yet)

    Wire D13 through 330 Ω resistor to LED anode; return cathode to GND.

  8. Build dual condition (Not yet)

    If water ≥ 20% AND temperature > 30°C then turn LED ON, else OFF.

  9. Bind sensor & output blocks (Not yet)

    Bind water read to potentiometer, temp read to MCP9808, writes to Green LED.

  10. Observe boundary scenarios (Not yet)

    Verify demand LED only turns ON when both conditions are satisfied.

Lesson check

Run the circuit when every build step is done. Completion needs three observed ON/OFF cycles with both one-second waits.

Cycles observed: 0 of 2

Completion is saved only in this browser. It is not synced to an account and is not a certificate.

Open the Code tab to read the generated C++: both delay(1000) waits appear inside the repeat loop. It is not compiled or flashed.

Hints
  • Use `and` logic block to combine water level ≥ 20 and temperature > 30.
  • The Green LED represents an irrigation status indicator, not an actual pump or solenoid valve.
Bill of Materials
  • arduino-uno-r3-a000066 (v1) × 1 — Microcontroller board (5V logic)
  • fritzing-half-breadboard-420 (v1) × 1 — Half-size prototyping breadboard
  • potentiometer-trimmer (v1) × 1 — 10 kΩ rotary trimmer (simulated water reservoir level)
  • adafruit-mcp9808-5027 (v1) × 1 — MCP9808 precision digital temperature sensor (I2C 0x18)
  • resistor-axial-series (v1) × 1 — 330 Ω LED current-limiting resistor
  • led-5mm-colour (v1) × 1 — 5mm green LED (irrigation demand indicator)
Wiring Explanation

Wire potentiometer to 5V, GND, and pin A0. Wire MCP9808 to 5V, GND, SCL, and SDA. Wire digital pin D13 through a 330 Ω resistor to the Green LED anode (+), and return cathode (−) to GND.

Draft lesson and translations — fluent educator review pending.

Board inspector

This project has no board yet.

Add a supported board to check wiring, simulate and preview code. Physical compatibility is unverified.

Lessons keep their board. Use a free project to try another board.

Wiring checks

Limited virtual teaching rules — not physical safety certification or a general electrical solver. Passing wiring checks does not run code or award completion.

Draft explanations and translations — fluent educator review pending.

Wiring checks blocked

Error: 0 · Warning: 0 · Unsupported: 1

  • Unsupported · missing-board

    This draft has no programmable board.

    Repair hint: Add a supported board and connect its named terminals explicitly.

    Involved IDs

    Parts tray

    Planned boards and parts

    Shown for planning only. They cannot be added, simulated or exported yet.

    • Raspberry Pi Pico W · RP2040 · Not available yet · Planned gate C
    • Raspberry Pi Pico 2 · RP2350 · Not available yet · Planned gate C
    • Raspberry Pi 4 Model B · other RAM sizes and PCB revisions · Not available yet · Planned gate D
    • BeagleBone Black Wireless · Not available yet · Planned gate D
    • Analog temperature and water-level circuit inputs · Not available yet · Planned gate C
    • Motors, servos, other displays and SPI/UART bus modules · Not available yet · Planned gate C

    Terminal inspector

    None

    Connections

    Use these labelled controls instead of dragging or selecting small terminals. Wires cross without joining.

    No wires yet.

    Select a part, then drag it or use arrow keys to move it. In Wire mode, choose two terminals. Visual overlap never creates electrical contact; use the attachment form to occupy a breadboard hole.

    Limited circuit simulation for the published UNO R3 and ESP32-DevKitC V4 teaching profiles. Code view offers qualified C++ and JavaScript previews (plus MicroPython for ESP32) with wiring manifests, plus document JSON. No CPU, Wi-Fi or Bluetooth is simulated, and physical compatibility is unverified.

    Draft learning copy and translations — fluent educator review is still required.

    Guest circuit projects

    Saved on this browser. Nothing uploads automatically; a signed-in adult or educator can press Save to cloud for a private copy. Download a copy before clearing browser data.

    Local save pending

    Draft explanations and en/rw/fr translations need fluent educator review.