.. note:: Hello, welcome to the SunFounder Raspberry Pi & Arduino & ESP32 Enthusiasts Community on Facebook! Dive deeper into Raspberry Pi, Arduino, and ESP32 with fellow enthusiasts. **Why Join?** - **Expert Support**: Solve post-sale issues and technical challenges with help from our community and team. - **Learn & Share**: Exchange tips and tutorials to enhance your skills. - **Exclusive Previews**: Get early access to new product announcements and sneak peeks. - **Special Discounts**: Enjoy exclusive discounts on our newest products. - **Festive Promotions and Giveaways**: Take part in giveaways and holiday promotions. 👉 Ready to explore and create with us? Click [|link_sf_facebook|] and join today! .. _ar_pir: 5.5 Detect Human Movement ======================================== Passive infrared sensor (PIR sensor) is a common sensor that can measure infrared (IR) light emitted by objects in its field of view. Simply put, it will receive infrared radiation emitted from the body, thereby detecting the movement of people and other animals. More specifically, it tells the main control board that someone has entered your room. **Required Components** In this project, we need the following components. It's definitely convenient to buy a whole kit, here's the link: .. list-table:: :widths: 20 20 20 :header-rows: 1 * - Name - ITEMS IN THIS KIT - LINK * - ESP32 Starter Kit - 320+ - |link_esp32_starter_kit| You can also buy them separately from the links below. .. list-table:: :widths: 30 20 :header-rows: 1 * - COMPONENT INTRODUCTION - PURCHASE LINK * - :ref:`cpn_esp32_wroom_32e` - |link_esp32_wroom_32e_buy| * - :ref:`cpn_esp32_camera_extension` - |link_esp32_extension_board| * - :ref:`cpn_breadboard` - |link_breadboard_buy| * - :ref:`cpn_wires` - |link_wires_buy| * - :ref:`cpn_resistor` - |link_resistor_buy| * - :ref:`cpn_led` - |link_led_buy| * - :ref:`cpn_pir` - |link_pir_buy| **Available Pins** * **Available Pins** Here is a list of available pins on the ESP32 board for this project. .. list-table:: :widths: 5 20 * - For Input - IO13, IO14, IO27, IO26, IO25, IO33, I35, I34, I39, I36, IO4, IO18, IO19, IO21, IO22, IO23 * - For Output - IO13, IO12, IO14, IO27, IO26, IO25, IO33, IO32, IO15, IO2, IO0, IO4, IO5, IO18, IO19, IO21, IO22, IO23 .. note:: IO32 cannot be used **as input pin** in this project because it is internally connected to a 1K pull-down resistor, which sets its default value to 0. * **Strapping Pins (Input)** Strapping pins are a special set of pins that are used to determine specific boot modes during device startup (i.e., power-on reset). .. list-table:: :widths: 5 15 * - Strapping Pins - IO5, IO0, IO2, IO12, IO15 Generally, it is **not recommended to use them as input pins**. If you wish to use these pins, consider the potential impact on the booting process. For more details, please refer to the :ref:`esp32_strapping` section. **Schematic** .. image:: ../../img/circuit/circuit_5.5_pir.png When the PIR module detects motion, IO14 will go high, and the LED will be lit. Otherwise, when no motion is detected, IO14 will be low, and the LED will turn off. .. note:: The PIR module has two potentiometers: one adjusts sensitivity, the other adjusts detection distance. To make the PIR module work better, you need to turn both of them counterclockwise to the end. .. image:: ../../components/img/PIR_TTE.png :width: 300 :align: center **Wiring** .. image:: ../../img/wiring/5.5_pir_bb.png **Code** .. note:: * You can open the file ``5.5_pir.ino`` under the path of ``esp32-starter-kit-main\c\codes\5.5_pir``. * After selecting the board (ESP32 Dev Module) and the appropriate port, click the **Upload** button. * :ref:`unknown_com_port` .. raw:: html After the code has been uploaded successfully, the LED will light up and then go off when the PIR module detects someone passing. .. note:: The PIR module has two potentiometers: one adjusts sensitivity, the other adjusts detection distance. To make the PIR module work better, you need to turn both of them counterclockwise to the end. .. image:: img/pir_back.png