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1581 lines
79 KiB
HTML
1581 lines
79 KiB
HTML
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Byte Rider 06-2025 documentation
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<h1 class="title-cover">
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Byte Rider
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</h1>
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<p class="subtitle-cover">
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Version
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<a href="#">
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Table of Contents
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</a>
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</h3>
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<ul>
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<li class="toctree-l1">
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<a class="reference internal" href="#overview">
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1. OVERVIEW
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</a>
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<ul>
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<li class="toctree-l2">
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<a class="reference internal" href="#abstract">
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1.1. ABSTRACT
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</a>
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</li>
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</ul>
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</li>
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<li class="toctree-l1">
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<a class="reference internal" href="#how-does-it-work">
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2. HOW DOES IT WORK?
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</a>
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<ul>
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<li class="toctree-l2">
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<a class="reference internal" href="#reserved-pins-gpios">
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2.1. Reserved Pins & GPIOs
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</a>
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<ul>
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<li class="toctree-l3">
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<a class="reference internal" href="#reading-the-joystick-x-and-y-axis">
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2.1.1. Reading the Joystick x- and y- axis
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</a>
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</li>
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<li class="toctree-l3">
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<a class="reference internal" href="#controlling-the-direction-and-speed">
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2.1.2. Controlling the Direction and Speed
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</a>
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</li>
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</ul>
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</li>
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<li class="toctree-l2">
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<a class="reference internal" href="#fusion-of-software-with-hardware">
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2.2. Fusion of Software with Hardware
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</a>
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</li>
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<li class="toctree-l2">
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<a class="reference internal" href="#schematic">
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2.3. Schematic
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</a>
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</li>
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</ul>
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</li>
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<li class="toctree-l1">
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<a class="reference internal" href="#data-structs">
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3. DATA STRUCTS
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</a>
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<ul>
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<li class="toctree-l2">
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<a class="reference internal" href="#data-payload">
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3.1. Data Payload
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</a>
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<ul>
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<li class="toctree-l3">
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<a class="reference internal" href="#why-use-attribute-packed">
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3.1.1. Why use __attribute((packed))?
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</a>
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</li>
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</ul>
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</li>
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</ul>
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</li>
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<li class="toctree-l1">
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<a class="reference internal" href="#transmitter">
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4. TRANSMITTER
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</a>
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<ul>
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<li class="toctree-l2">
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<a class="reference internal" href="#configuration-variables">
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4.1. Configuration Variables
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</a>
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</li>
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<li class="toctree-l2">
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<a class="reference internal" href="#reading-joystick-x-and-y-axis-values">
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4.2. Reading Joystick x- and y- Axis Values
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</a>
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</li>
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<li class="toctree-l2">
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<a class="reference internal" href="#sending-ecapsulating-data">
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4.3. Sending & Ecapsulating Data
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</a>
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</li>
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<li class="toctree-l2">
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<a class="reference internal" href="#main-function">
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4.4. Main Function
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</a>
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</li>
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</ul>
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</li>
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<li class="toctree-l1">
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<a class="reference internal" href="#receiver">
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5. RECEIVER
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</a>
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<ul>
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<li class="toctree-l2">
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<a class="reference internal" href="#configuration-variables">
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5.1. Configuration Variables
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</a>
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</li>
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<li class="toctree-l2">
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<a class="reference internal" href="#receiving-extracting-data">
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5.2. Receiving & Extracting Data
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</a>
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</li>
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<li class="toctree-l2">
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<a class="reference internal" href="#main-function">
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5.3. Main Function
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</a>
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</li>
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</ul>
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</li>
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<li class="toctree-l1">
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<a class="reference internal" href="#work-in-progress-walk-through">
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6. WORK-IN-PROGRESS WALK THROUGH
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</a>
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<ul>
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<li class="toctree-l2">
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<a class="reference internal" href="#finished-work">
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6.1. Finished Work
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</a>
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</li>
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<li class="toctree-l2">
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<a class="reference internal" href="#chassis">
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6.2. Chassis
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</a>
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</li>
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<li class="toctree-l2">
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<a class="reference internal" href="#wiring">
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6.3. Wiring
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</a>
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</li>
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<li class="toctree-l2">
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<a class="reference internal" href="#motor-wires-harness">
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6.4. Motor Wires Harness
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</a>
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</li>
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</ul>
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</li>
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<li class="toctree-l1">
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<a class="reference internal" href="#references">
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7. REFERENCES
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</a>
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<ul>
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<li class="toctree-l2">
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<a class="reference internal" href="#github">
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7.1. GitHub
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</a>
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</li>
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</ul>
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</li>
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</ul>
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</div>
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</div>
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</div>
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<div class="document">
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<div class="documentwrapper">
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<div class="bodywrapper">
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<div class="body" role="main">
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<section id="byterider-highlights">
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<h1>
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ByteRider Highlights
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<a class="headerlink" href="#byterider-highlights" title="Link to this heading">
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¶
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</a>
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</h1>
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<img alt="_images/ESP-IDF_Robot.jpg" src="_images/ESP-IDF_Robot.jpg"/>
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<div class="toctree-wrapper compound">
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<span id="document-intro">
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</span>
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<section id="overview">
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<h2>
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OVERVIEW
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<a class="headerlink" href="#overview" title="Link to this heading">
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¶
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</a>
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</h2>
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<p>
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At the heart of this project is ESP32-C3 IoT Link, which enables a customizable remote-controlled car to respond to real-time
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control inputs, handle speed adjustments, directional changes, and even extend features like measuring system telemetry values
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such as voltage, current, temperature, etc. The foundational setup uses ESP-NOW for transmitter and receiver devices,
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allowing you to control the car’s behaviour wirelessly. While the design and physical appearance of the RC car can vary wildly
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depending on your creativity and available hardware, the control system remains the same. To facilitate wireless communication
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between devices, the system employs IoT Link powered by ESP-NOW, which is a lightweight and connection-free protocol ideal for fast,
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low-latency data transmission between ESP32 microcontrollers.
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</p>
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<p>
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The control values are sent wirelessly to the remotely controlled car using the ESP-NOW protocol. ESP-NOW enables fast and efficient
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communication between ESP32 devices without the need for a Wi-Fi router, network, or pairing. The provided tutorial demonstrates a
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functional setup where a transmitter encapsulates and sends data to a receiver to define the car’s speed and direction, forming the
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core communication loop. While the baseline implementation focuses on movement, additional features like lights, sensors, or
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telemetry can easily be integrated by expanding the source code. This modular design gives you the freedom to customize both the
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appearance and behaviour of your RC car, resulting in endless creative possibilities.
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</p>
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<section id="abstract">
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<h3>
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ABSTRACT
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<a class="headerlink" href="#abstract" title="Link to this heading">
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¶
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</a>
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</h3>
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<p>
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To enable real-time remote operation of the RC car, the system translates joystick x- and y- axis inputs into PWM (Pulse Width Modulation) signals that control the DC motors.
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These PWM values are stored in a predefined data structure, which is then transmitted wirelessly using ESP-NOW — a low-latency, connectionless
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communication protocol developed by Espressif. Both the transmitter and receiver modules are based on ESP32-C3 microcontrollers.
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</p>
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<p>
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On the transmitter side, the joystick’s X and Y coordinates are continuously monitored and converted into PWM parameters. These values are packed into the
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data structure and sent via ESP-NOW to the receiver.
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</p>
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<p>
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The receiver module listens for incoming ESP-NOW packets, extracts the PWM control data, and applies it directly to the DC motors. This communication flow
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allows the RC car to respond instantly to user input, managing speed and direction without any physical connection between the devices.
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</p>
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</section>
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</section>
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<span id="document-overview">
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</span>
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<section id="how-does-it-work">
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<h2>
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HOW DOES IT WORK?
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<a class="headerlink" href="#how-does-it-work" title="Link to this heading">
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¶
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</a>
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</h2>
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<p>
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The bitByteRider RC car is powered by ESP32-C3 bitBoard. The Schematic and KiCAd PCB board files are available
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on
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<a class="reference external" href="https://github.com/alexandrebobkov/ESP32-C3_Breadboard-Adapter">
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GitHub
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</a>
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:
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<a class="reference external" href="https://github.com/alexandrebobkov/ESP32-C3_Breadboard-Adapter">
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https://github.com/alexandrebobkov/ESP32-C3_Breadboard-Adapter
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</a>
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</p>
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<p>
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The bitByteRider RC car operates using two main units: the
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<em>
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transmitter
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</em>
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, which reads and sends the joystick’s X and Y values, and
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the
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<em>
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receiver
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</em>
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, which interprets these values and converts them into PWM signals to control the DC motors. Both units communicate
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via
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<strong>
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ESP-NOW
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</strong>
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, a low-latency, connectionless wireless protocol that requires no Wi-Fi network or pairing.
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</p>
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<p>
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In addition to enabling real-time control, using ESP-NOW introduces key networking concepts such as
|
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<strong>
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data encapsulation
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</strong>
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and
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structured communication. By using data structures to group control variables, you gain hands-on experience with how information
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is packaged and transmitted, laying the groundwork for understanding the fundamentals of network communication in embedded systems.
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</p>
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<p>
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The joystick used in the bitByteRider RC car remote unit outputs analog voltages ranging from 0V to 3.3V on both the x- and y-axes,
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depending on the position of the joystick. These voltage levels are read by the ESP32-C3’s ADC (Analog-to-Digital Converter) inputs.
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</p>
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<p>
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When the joystick is in its neutral (centred) position, the ADC inputs on the ESP32-C3 receive approximately 1.65V on both axes.
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This midpoint voltage is interpreted and interpolated into a PWM (Pulse Width Modulation) value of 0, indicating no movement or
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motor activity.
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</p>
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<p>
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As the joystick is pushed to its maximum positions along the x- and y-axis, the voltage increases up to 3.3V. This maximum voltage
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is interpolated to a PWM value of 1024, which corresponds to a 100% duty cycle on the receiver side, resulting in full-speed
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operation of the DC motors.
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</p>
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<p>
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To transmit control data, the X and Y axis values are encapsulated in a C struct, along with the receiver’s
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<strong>
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MAC
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</strong>
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address, and sent
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wirelessly using ESP-NOW. This protocol enables low-latency, connectionless communication between the transmitter and receiver
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without requiring a Wi-Fi network or pairing.
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</p>
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<p>
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Upon reception, the RC car’s receiver decapsulates the data, extracts the joystick values, and interpolates them into PWM
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signals. These signals are then used to control the rotation speeds of the DC motors, enabling smooth and responsive remote control.
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</p>
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<p>
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This process not only facilitates real-time control but also introduces you to key networking concepts such as data
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encapsulation, data structs, and the fundamentals of wireless data transmission in embedded systems.
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</p>
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<div class="admonition-what-is-encapsulation admonition">
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<p class="admonition-title">
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What is encapsulation?
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</p>
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<p>
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Encapsulation refers to the process of organizing and packaging data into a structured format before it is transmitted between
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devices. This is a fundamental concept in networking and communication protocols, including those used in IoT systems.
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</p>
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</div>
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<section id="reserved-pins-gpios">
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<h3>
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Reserved Pins & GPIOs
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<a class="headerlink" href="#reserved-pins-gpios" title="Link to this heading">
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¶
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</a>
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</h3>
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<p>
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The following table summarizes GPIOs and pins reserved for operations purposes.
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</p>
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<p>
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The GPIO numbers correspond to those on the ESP32-C3 WROOM microcontroller. The Pin number corresponds to the pin on the Breadboard and Power adapter development board.
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</p>
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<section id="reading-the-joystick-x-and-y-axis">
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<h4>
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Reading the Joystick x- and y- axis
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<a class="headerlink" href="#reading-the-joystick-x-and-y-axis" title="Link to this heading">
|
|
¶
|
|
</a>
|
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</h4>
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<p>
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To determine the position of the Joystick, the BitRider RC car uses ADC to measure voltage on two GPIOs connected to the joystick
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x- and y- axis potentionometers (
|
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<strong>
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|
GPIO0
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</strong>
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and
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<strong>
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|
GPIO1
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</strong>
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).
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</p>
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</section>
|
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<section id="controlling-the-direction-and-speed">
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<h4>
|
|
Controlling the Direction and Speed
|
|
<a class="headerlink" href="#controlling-the-direction-and-speed" title="Link to this heading">
|
|
¶
|
|
</a>
|
|
</h4>
|
|
<p>
|
|
To set any desired speed of BiteRider RC car, the
|
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<em>
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|
ESP32-C3 Breadboard Adapter DevBoard
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</em>
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uses PWM to control the rotation speed
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of DR motors. Similarly, to set the direction of the RC car, the rotation speed of corresponding DC motors is changed as required.
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</p>
|
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<p>
|
|
Due to the design and limited number of available GPIOs, the
|
|
<em>
|
|
ESP32-C3 Breadboard DevBoard
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</em>
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|
can control rotation speed and direction
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of DC motors in pairs only (i.e. left and right side). Consequently, this means that the four PWM channels used for controlling the
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direction of the RC car.
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</p>
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<p>
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Based on this constraint, the RC car can only move front, back, and turn/rotate left and right. Any other movements are not
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possible (i.e. diagonal or sideways).
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</p>
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<table class="docutils align-default">
|
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<tbody>
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<tr class="row-odd">
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<td>
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<p>
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|
PWM of DC Motors
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</p>
|
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</td>
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<td>
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<p>
|
|
Direction
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</p>
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</td>
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</tr>
|
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<tr class="row-even">
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<td>
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<p>
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|
PWM(left) = PWM(right)
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</p>
|
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</td>
|
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<td>
|
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<p>
|
|
Straight
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</p>
|
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</td>
|
|
</tr>
|
|
<tr class="row-odd">
|
|
<td>
|
|
<p>
|
|
PWM(left) > PWM(right)
|
|
</p>
|
|
</td>
|
|
<td>
|
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<p>
|
|
Left
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</p>
|
|
</td>
|
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</tr>
|
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<tr class="row-even">
|
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<td>
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<p>
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|
PWM(left) < PWM(right)
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</p>
|
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</td>
|
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<td>
|
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<p>
|
|
Right
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</p>
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</td>
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</tr>
|
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</tbody>
|
|
</table>
|
|
<div class="admonition-what-is-pwm admonition">
|
|
<p class="admonition-title">
|
|
What is PWM?
|
|
</p>
|
|
<p>
|
|
<strong>
|
|
PWM
|
|
</strong>
|
|
stands for Pulse Width Modulation. It is a technique used to simulate analog voltage levels using discrete digital signals. It works by
|
|
rapidly switching a digital GPIO pin between HIGH (on) and LOW (off) states at a fixed frequency (often, at base frequency of 5 kHz).
|
|
The duty cycle—the percentage of time the signal is HIGH in one cycle determines the effective voltage delivered to a device.
|
|
A higher duty cycle increases the motor speed, and a lower duty cycle decreases the motor speed. This allows for fine-grained speed control
|
|
without needing analog voltage regulators.
|
|
</p>
|
|
</div>
|
|
<p>
|
|
A pair of PWM channels are used per DC motor for defining their rotation speed and direction on each side.
|
|
In particular,
|
|
<strong>
|
|
GPIO6
|
|
</strong>
|
|
and
|
|
<strong>
|
|
GPIO5
|
|
</strong>
|
|
provide PWM to the left- and right- side DC motors to rotate in a
|
|
<strong>
|
|
clockwise
|
|
</strong>
|
|
direction.
|
|
Similarly,
|
|
<strong>
|
|
GPIO4
|
|
</strong>
|
|
and
|
|
<strong>
|
|
GPIO7
|
|
</strong>
|
|
provide PWM to the left- and right- side DC motors to rotate in a
|
|
<strong>
|
|
counter-clockwise
|
|
</strong>
|
|
direction.
|
|
Changing PWM on each channel determines the speed and direction of the RC car.
|
|
</p>
|
|
<p>
|
|
The table below summarizes the GPIO pins used for PWM to control the direction of the DC motors in the remote-controlled car.
|
|
</p>
|
|
<table class="docutils align-default">
|
|
<thead>
|
|
<tr class="row-odd">
|
|
<th class="head">
|
|
<p>
|
|
GPIOs
|
|
</p>
|
|
</th>
|
|
<th class="head">
|
|
<p>
|
|
State
|
|
</p>
|
|
</th>
|
|
<th class="head">
|
|
<p>
|
|
Description
|
|
</p>
|
|
</th>
|
|
<th class="head">
|
|
<p>
|
|
Function
|
|
</p>
|
|
</th>
|
|
</tr>
|
|
</thead>
|
|
<tbody>
|
|
<tr class="row-even">
|
|
<td>
|
|
<p>
|
|
GPIO6,
|
|
GPIO4
|
|
</p>
|
|
</td>
|
|
<td>
|
|
<p>
|
|
PWM
|
|
</p>
|
|
</td>
|
|
<td>
|
|
<p>
|
|
Left & Right DC Motors spin
|
|
clockwise
|
|
</p>
|
|
</td>
|
|
<td>
|
|
<p>
|
|
Forward
|
|
</p>
|
|
</td>
|
|
</tr>
|
|
<tr class="row-odd">
|
|
<td>
|
|
<p>
|
|
GPIO5,
|
|
GPIO7
|
|
</p>
|
|
</td>
|
|
<td>
|
|
<p>
|
|
PWM
|
|
</p>
|
|
</td>
|
|
<td>
|
|
<p>
|
|
Left & Right DC Motors spin
|
|
counterclockwise
|
|
</p>
|
|
</td>
|
|
<td>
|
|
<p>
|
|
Reverse
|
|
</p>
|
|
</td>
|
|
</tr>
|
|
<tr class="row-even">
|
|
<td>
|
|
<p>
|
|
GPIO6,
|
|
GPIO7
|
|
</p>
|
|
</td>
|
|
<td>
|
|
<p>
|
|
PWM
|
|
</p>
|
|
</td>
|
|
<td>
|
|
<p>
|
|
Left DC Motors spin clockwise.
|
|
Right DC Motors spin counterclockwise
|
|
</p>
|
|
</td>
|
|
<td>
|
|
<p>
|
|
Left
|
|
</p>
|
|
</td>
|
|
</tr>
|
|
<tr class="row-odd">
|
|
<td>
|
|
<p>
|
|
GPIO4,
|
|
GPIO5
|
|
</p>
|
|
</td>
|
|
<td>
|
|
<p>
|
|
PWM
|
|
</p>
|
|
</td>
|
|
<td>
|
|
<p>
|
|
Left DC Motors spin counterclockwise.
|
|
Right DC Motors spin clockwise
|
|
</p>
|
|
</td>
|
|
<td>
|
|
<p>
|
|
Right
|
|
</p>
|
|
</td>
|
|
</tr>
|
|
</tbody>
|
|
</table>
|
|
<p>
|
|
The following images illustrate various PWM duty cycles registered by oscilloscope (duty cycles 0%, 48% and 91%, resp.).
|
|
</p>
|
|
<figure class="align-default" id="id1">
|
|
<img alt="_images/ESP-IDF_Robot_PWM_Duty-0.bmp" src="_images/ESP-IDF_Robot_PWM_Duty-0.bmp"/>
|
|
<figcaption>
|
|
<p>
|
|
<span class="caption-text">
|
|
DC Motor PWM duty cycle 0%
|
|
</span>
|
|
<a class="headerlink" href="#id1" title="Link to this image">
|
|
¶
|
|
</a>
|
|
</p>
|
|
</figcaption>
|
|
</figure>
|
|
<figure class="align-default" id="id2">
|
|
<img alt="_images/ESP-IDF_Robot_PWM_Duty-50.bmp" src="_images/ESP-IDF_Robot_PWM_Duty-50.bmp"/>
|
|
<figcaption>
|
|
<p>
|
|
<span class="caption-text">
|
|
DC Motor PWM duty cycle 47.6%
|
|
</span>
|
|
<a class="headerlink" href="#id2" title="Link to this image">
|
|
¶
|
|
</a>
|
|
</p>
|
|
</figcaption>
|
|
</figure>
|
|
<figure class="align-default" id="id3">
|
|
<img alt="_images/ESP-IDF_Robot_PWM_Duty-95.bmp" src="_images/ESP-IDF_Robot_PWM_Duty-95.bmp"/>
|
|
<figcaption>
|
|
<p>
|
|
<span class="caption-text">
|
|
DC Motor PWM duty cycle 90.8%
|
|
</span>
|
|
<a class="headerlink" href="#id3" title="Link to this image">
|
|
¶
|
|
</a>
|
|
</p>
|
|
</figcaption>
|
|
</figure>
|
|
<br/>
|
|
<br/>
|
|
<br/>
|
|
<br/>
|
|
</section>
|
|
</section>
|
|
<section id="fusion-of-software-with-hardware">
|
|
<h3>
|
|
Fusion of Software with Hardware
|
|
<a class="headerlink" href="#fusion-of-software-with-hardware" title="Link to this heading">
|
|
¶
|
|
</a>
|
|
</h3>
|
|
<p>
|
|
On one hand, we have the hardware designed so that the joystic x- and y- axis, and DC motors are wired to the proper GPIOs on the
|
|
ESP32-C3 WROOM microcontroller. On the other hand, we have the software that reads the joystick x- and y- axis, sends the data
|
|
to the receiver device, and converts that to PWM values on the receiver device.
|
|
</p>
|
|
<p>
|
|
In essense, the direction and speed of the bitByte Rider car is controlled by the two variables. On the remote controller device,
|
|
the joystic x- and y- axis values are sent to the receiver device in a raw format (i.e. analog voltages, “as-is”). On the receover
|
|
device, these two values are converted to the two PWM values; one for each pair of DC motors on left and right side.
|
|
</p>
|
|
<p>
|
|
When the joystick is pushed forward, the X-axis voltage remains at 1.65V (neutral), while the Y-axis voltage rises to 3.3V. The
|
|
receiver on the RC car interprets this input and generates 100% PWM duty cycle signals on both sides, driving the car forward at
|
|
full speed.
|
|
</p>
|
|
<p>
|
|
Similarly, when the joystick is pushed fully to the left or right, the X-axis voltage shifts while the Y-axis remains neutral. For a
|
|
left turn, the receiver translates the signal into 100% PWM on the left-side motors and 0% on the right-side motors, causing the car
|
|
to pivot. The opposite occurs for a right turn, with 100% PWM on the right and 0% on the left, enabling precise directional control.
|
|
</p>
|
|
<p>
|
|
The table below summarizes the reserved GPIOs. These GPIOs are hard-wired to the corresponding components, and hard-coded in the
|
|
corresponding functions. For example, the GPIOs 0 and 1 are hard-wired to the joystick x- and y- axis, respectively; and, hard-coded
|
|
to read analog values and store them in the corresponding x- and y- variables.
|
|
</p>
|
|
<table class="docutils align-default">
|
|
<thead>
|
|
<tr class="row-odd">
|
|
<th class="head">
|
|
<p>
|
|
GPIO
|
|
</p>
|
|
</th>
|
|
<th class="head">
|
|
<p>
|
|
Pin
|
|
</p>
|
|
</th>
|
|
<th class="head">
|
|
<p>
|
|
Function
|
|
</p>
|
|
</th>
|
|
<th class="head">
|
|
<p>
|
|
Notes
|
|
</p>
|
|
</th>
|
|
</tr>
|
|
</thead>
|
|
<tbody>
|
|
<tr class="row-even">
|
|
<td>
|
|
<p>
|
|
0
|
|
</p>
|
|
</td>
|
|
<td>
|
|
<p>
|
|
16
|
|
</p>
|
|
</td>
|
|
<td>
|
|
<p>
|
|
Joystick x-axis
|
|
</p>
|
|
</td>
|
|
<td>
|
|
<p>
|
|
ADC1_CH0
|
|
</p>
|
|
</td>
|
|
</tr>
|
|
<tr class="row-odd">
|
|
<td>
|
|
<p>
|
|
1
|
|
</p>
|
|
</td>
|
|
<td>
|
|
<p>
|
|
15
|
|
</p>
|
|
</td>
|
|
<td>
|
|
<p>
|
|
Joystick y-axis
|
|
</p>
|
|
</td>
|
|
<td>
|
|
<p>
|
|
ADC1_CH1
|
|
</p>
|
|
</td>
|
|
</tr>
|
|
<tr class="row-even">
|
|
<td>
|
|
<p>
|
|
8
|
|
</p>
|
|
</td>
|
|
<td>
|
|
<p>
|
|
5
|
|
</p>
|
|
</td>
|
|
<td>
|
|
<p>
|
|
Joystick push button
|
|
</p>
|
|
</td>
|
|
<td>
|
|
<p>
|
|
NC
|
|
</p>
|
|
</td>
|
|
</tr>
|
|
<tr class="row-odd">
|
|
<td>
|
|
<p>
|
|
6
|
|
</p>
|
|
</td>
|
|
<td>
|
|
<p>
|
|
4
|
|
</p>
|
|
</td>
|
|
<td>
|
|
<p>
|
|
PWM for clockwise rotation of left-side motors
|
|
</p>
|
|
</td>
|
|
<td>
|
|
<p>
|
|
LEDC_CHANNEL_1
|
|
</p>
|
|
</td>
|
|
</tr>
|
|
<tr class="row-even">
|
|
<td>
|
|
<p>
|
|
5
|
|
</p>
|
|
</td>
|
|
<td>
|
|
<p>
|
|
3
|
|
</p>
|
|
</td>
|
|
<td>
|
|
<p>
|
|
PWM for clockwise rotation of right-side motors
|
|
</p>
|
|
</td>
|
|
<td>
|
|
<p>
|
|
LEDC_CHANNEL_0
|
|
</p>
|
|
</td>
|
|
</tr>
|
|
<tr class="row-odd">
|
|
<td>
|
|
<p>
|
|
4
|
|
</p>
|
|
</td>
|
|
<td>
|
|
<p>
|
|
2
|
|
</p>
|
|
</td>
|
|
<td>
|
|
<p>
|
|
PWM for counter-clockwise rotation of right-side motors
|
|
</p>
|
|
</td>
|
|
<td>
|
|
<p>
|
|
LEDC_CHANNEL_2
|
|
</p>
|
|
</td>
|
|
</tr>
|
|
<tr class="row-even">
|
|
<td>
|
|
<p>
|
|
7
|
|
</p>
|
|
</td>
|
|
<td>
|
|
<p>
|
|
6
|
|
</p>
|
|
</td>
|
|
<td>
|
|
<p>
|
|
PWM for counter-clockwise rotation of left-side motors
|
|
</p>
|
|
</td>
|
|
<td>
|
|
<p>
|
|
LEDC_CHANNEL_3
|
|
</p>
|
|
</td>
|
|
</tr>
|
|
</tbody>
|
|
</table>
|
|
<p>
|
|
The struct used to store motor PWM values is shown below. While the bitByteRider RC car can be effectively controlled using
|
|
just two PWM signals—one for each side—the structure is designed to hold four values, allowing room for future enhancements. This
|
|
forward-thinking design supports potential upgrades such as improved maneuverability, individual wheel control, or advanced driving
|
|
modes, making the system more adaptable and scalable for future development.
|
|
</p>
|
|
<div class="highlight-c notranslate">
|
|
<div class="highlight">
|
|
<pre><span></span><span class="k">struct</span><span class="w"> </span><span class="nc">motors_rpm</span><span class="w"> </span><span class="p">{</span>
|
|
<span class="w"> </span><span class="kt">int</span><span class="w"> </span><span class="n">motor1_rpm_pwm</span><span class="p">;</span>
|
|
<span class="w"> </span><span class="kt">int</span><span class="w"> </span><span class="n">motor2_rpm_pwm</span><span class="p">;</span>
|
|
<span class="w"> </span><span class="kt">int</span><span class="w"> </span><span class="n">motor3_rpm_pwm</span><span class="p">;</span>
|
|
<span class="w"> </span><span class="kt">int</span><span class="w"> </span><span class="n">motor4_rpm_pwm</span><span class="p">;</span>
|
|
<span class="p">};</span>
|
|
</pre>
|
|
</div>
|
|
</div>
|
|
<p>
|
|
On the transmitter device, the PWM values for the DC motors are sent to the receiver using the following function. The variable
|
|
<strong>
|
|
receiver_mac
|
|
</strong>
|
|
stores the MAC address of the receiver device (ESP32-C3 bitBoard on the RC car).
|
|
</p>
|
|
<div class="highlight-c notranslate">
|
|
<div class="highlight">
|
|
<pre><span></span><span class="c1">// Function to send data to the receiver</span>
|
|
<span class="kt">void</span><span class="w"> </span><span class="nf">sendData</span><span class="w"> </span><span class="p">(</span><span class="kt">void</span><span class="p">)</span><span class="w"> </span><span class="p">{</span>
|
|
<span class="w"> </span><span class="n">sensors_data_t</span><span class="w"> </span><span class="n">buffer</span><span class="p">;</span><span class="w"> </span><span class="c1">// Declare data struct</span>
|
|
|
|
<span class="w"> </span><span class="n">buffer</span><span class="p">.</span><span class="n">crc</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="mi">0</span><span class="p">;</span>
|
|
<span class="w"> </span><span class="n">buffer</span><span class="p">.</span><span class="n">x_axis</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="mi">0</span><span class="p">;</span>
|
|
<span class="w"> </span><span class="n">buffer</span><span class="p">.</span><span class="n">y_axis</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="mi">0</span><span class="p">;</span>
|
|
<span class="w"> </span><span class="n">buffer</span><span class="p">.</span><span class="n">nav_bttn</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="mi">0</span><span class="p">;</span>
|
|
<span class="w"> </span><span class="n">buffer</span><span class="p">.</span><span class="n">motor1_rpm_pwm</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="mi">0</span><span class="p">;</span>
|
|
<span class="w"> </span><span class="n">buffer</span><span class="p">.</span><span class="n">motor2_rpm_pwm</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="mi">0</span><span class="p">;</span>
|
|
<span class="w"> </span><span class="n">buffer</span><span class="p">.</span><span class="n">motor3_rpm_pwm</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="mi">0</span><span class="p">;</span>
|
|
<span class="w"> </span><span class="n">buffer</span><span class="p">.</span><span class="n">motor4_rpm_pwm</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="mi">0</span><span class="p">;</span>
|
|
|
|
<span class="w"> </span><span class="c1">// Display brief summary of data being sent.</span>
|
|
<span class="w"> </span><span class="n">ESP_LOGI</span><span class="p">(</span><span class="n">TAG</span><span class="p">,</span><span class="w"> </span><span class="s">"Joystick (x,y) position ( 0x%04X, 0x%04X )"</span><span class="p">,</span><span class="w"> </span><span class="p">(</span><span class="kt">uint8_t</span><span class="p">)</span><span class="n">buffer</span><span class="p">.</span><span class="n">x_axis</span><span class="p">,</span><span class="w"> </span><span class="p">(</span><span class="kt">uint8_t</span><span class="p">)</span><span class="n">buffer</span><span class="p">.</span><span class="n">y_axis</span><span class="p">);</span>
|
|
<span class="w"> </span><span class="n">ESP_LOGI</span><span class="p">(</span><span class="n">TAG</span><span class="p">,</span><span class="w"> </span><span class="s">"pwm 1, pwm 2 [ 0x%04X, 0x%04X ]"</span><span class="p">,</span><span class="w"> </span><span class="p">(</span><span class="kt">uint8_t</span><span class="p">)</span><span class="n">buffer</span><span class="p">.</span><span class="n">pwm</span><span class="p">,</span><span class="w"> </span><span class="p">(</span><span class="kt">uint8_t</span><span class="p">)</span><span class="n">buffer</span><span class="p">.</span><span class="n">pwm</span><span class="p">);</span>
|
|
<span class="w"> </span><span class="n">ESP_LOGI</span><span class="p">(</span><span class="n">TAG</span><span class="p">,</span><span class="w"> </span><span class="s">"pwm 3, pwm 4 [ 0x%04X, 0x%04X ]"</span><span class="p">,</span><span class="w"> </span><span class="p">(</span><span class="kt">uint8_t</span><span class="p">)</span><span class="n">buffer</span><span class="p">.</span><span class="n">pwm</span><span class="p">,</span><span class="w"> </span><span class="p">(</span><span class="kt">uint8_t</span><span class="p">)</span><span class="n">buffer</span><span class="p">.</span><span class="n">pwm</span><span class="p">);</span>
|
|
|
|
<span class="w"> </span><span class="c1">// Call ESP-NOW function to send data (MAC address of receiver, pointer to the memory holding data & data length)</span>
|
|
<span class="w"> </span><span class="kt">uint8_t</span><span class="w"> </span><span class="n">result</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">esp_now_send</span><span class="p">(</span><span class="n">receiver_mac</span><span class="p">,</span><span class="w"> </span><span class="o">&</span><span class="n">buffer</span><span class="p">,</span><span class="w"> </span><span class="k">sizeof</span><span class="p">(</span><span class="n">buffer</span><span class="p">));</span>
|
|
|
|
<span class="w"> </span><span class="c1">// If status is NOT OK, display error message and error code (in hexadecimal).</span>
|
|
<span class="w"> </span><span class="k">if</span><span class="w"> </span><span class="p">(</span><span class="n">result</span><span class="w"> </span><span class="o">!=</span><span class="w"> </span><span class="mi">0</span><span class="p">)</span><span class="w"> </span><span class="p">{</span>
|
|
<span class="w"> </span><span class="n">ESP_LOGE</span><span class="p">(</span><span class="s">"ESP-NOW"</span><span class="p">,</span><span class="w"> </span><span class="s">"Error sending data! Error code: 0x%04X"</span><span class="p">,</span><span class="w"> </span><span class="n">result</span><span class="p">);</span>
|
|
<span class="w"> </span><span class="n">deletePeer</span><span class="p">();</span>
|
|
<span class="w"> </span><span class="p">}</span>
|
|
<span class="w"> </span><span class="k">else</span>
|
|
<span class="w"> </span><span class="n">ESP_LOGW</span><span class="p">(</span><span class="s">"ESP-NOW"</span><span class="p">,</span><span class="w"> </span><span class="s">"Data was sent."</span><span class="p">);</span>
|
|
<span class="p">}</span>
|
|
</pre>
|
|
</div>
|
|
</div>
|
|
<p>
|
|
This function is invoked by a dedicated FreeRTOS task every 100 milliseconds, ensuring consistent and timely transmission of
|
|
control data to the receiver device. By leveraging FreeRTOS’s precise task scheduling, the system maintains low-latency
|
|
communication and predictable behaviour, critical for real-time control in embedded applications.
|
|
</p>
|
|
<div class="highlight-c notranslate">
|
|
<div class="highlight">
|
|
<pre><span></span><span class="c1">// Continous, periodic task that sends data.</span>
|
|
<span class="k">static</span><span class="w"> </span><span class="kt">void</span><span class="w"> </span><span class="nf">rc_send_data_task</span><span class="w"> </span><span class="p">(</span><span class="kt">void</span><span class="w"> </span><span class="o">*</span><span class="n">arg</span><span class="p">)</span><span class="w"> </span><span class="p">{</span>
|
|
|
|
<span class="w"> </span><span class="k">while</span><span class="w"> </span><span class="p">(</span><span class="nb">true</span><span class="p">)</span><span class="w"> </span><span class="p">{</span>
|
|
<span class="w"> </span><span class="k">if</span><span class="w"> </span><span class="p">(</span><span class="n">esp_now_is_peer_exist</span><span class="p">(</span><span class="n">receiver_mac</span><span class="p">))</span>
|
|
<span class="w"> </span><span class="n">sendData</span><span class="p">();</span>
|
|
<span class="w"> </span><span class="n">vTaskDelay</span><span class="w"> </span><span class="p">(</span><span class="mi">100</span><span class="w"> </span><span class="o">/</span><span class="w"> </span><span class="n">portTICK_PERIOD_MS</span><span class="p">);</span>
|
|
<span class="w"> </span><span class="p">}</span>
|
|
<span class="p">}</span>
|
|
</pre>
|
|
</div>
|
|
</div>
|
|
<p>
|
|
As data is being sent, the function onDataSent() is called to check & display the status of the data transmission.
|
|
</p>
|
|
<div class="highlight-c notranslate">
|
|
<div class="highlight">
|
|
<pre><span></span><span class="c1">// Call-back for the event when data is being sent</span>
|
|
<span class="kt">void</span><span class="w"> </span><span class="nf">onDataSent</span><span class="w"> </span><span class="p">(</span><span class="kt">uint8_t</span><span class="w"> </span><span class="o">*</span><span class="n">mac_addr</span><span class="p">,</span><span class="w"> </span><span class="n">esp_now_send_status_t</span><span class="w"> </span><span class="n">status</span><span class="p">)</span><span class="w"> </span><span class="p">{</span>
|
|
<span class="w"> </span><span class="n">ESP_LOGW</span><span class="p">(</span><span class="n">TAG</span><span class="p">,</span><span class="w"> </span><span class="s">"Packet send status: 0x%04X"</span><span class="p">,</span><span class="w"> </span><span class="n">status</span><span class="p">);</span>
|
|
<span class="p">}</span>
|
|
|
|
<span class="p">...</span><span class="w"> </span><span class="p">...</span><span class="w"> </span><span class="p">...</span>
|
|
<span class="p">...</span><span class="w"> </span><span class="p">...</span><span class="w"> </span><span class="p">...</span>
|
|
</pre>
|
|
</div>
|
|
</div>
|
|
<p>
|
|
On the receiver device, the data is saved in the variables by the call-back function onDataReceived().
|
|
</p>
|
|
<div class="highlight-c notranslate">
|
|
<div class="highlight">
|
|
<pre><span></span><span class="c1">// Call-back for the event when data is being received</span>
|
|
<span class="kt">void</span><span class="w"> </span><span class="nf">onDataReceived</span><span class="w"> </span><span class="p">(</span><span class="kt">uint8_t</span><span class="w"> </span><span class="o">*</span><span class="n">mac_addr</span><span class="p">,</span><span class="w"> </span><span class="kt">uint8_t</span><span class="w"> </span><span class="o">*</span><span class="n">data</span><span class="p">,</span><span class="w"> </span><span class="kt">uint8_t</span><span class="w"> </span><span class="n">data_len</span><span class="p">)</span><span class="w"> </span><span class="p">{</span>
|
|
|
|
<span class="w"> </span><span class="n">buf</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="p">(</span><span class="n">sensors_data_t</span><span class="o">*</span><span class="p">)</span><span class="n">data</span><span class="p">;</span><span class="w"> </span><span class="c1">// Allocate memory for buffer to store data being received</span>
|
|
<span class="w"> </span><span class="n">ESP_LOGW</span><span class="p">(</span><span class="n">TAG</span><span class="p">,</span><span class="w"> </span><span class="s">"Data was received"</span><span class="p">);</span>
|
|
<span class="w"> </span><span class="n">ESP_LOGI</span><span class="p">(</span><span class="n">TAG</span><span class="p">,</span><span class="w"> </span><span class="s">"x-axis: 0x%04x"</span><span class="p">,</span><span class="w"> </span><span class="n">buf</span><span class="o">-></span><span class="n">x_axis</span><span class="p">);</span>
|
|
<span class="w"> </span><span class="n">ESP_LOGI</span><span class="p">(</span><span class="n">TAG</span><span class="p">,</span><span class="w"> </span><span class="s">"x-axis: 0x%04x"</span><span class="p">,</span><span class="w"> </span><span class="n">buf</span><span class="o">-></span><span class="n">y_axis</span><span class="p">);</span>
|
|
<span class="w"> </span><span class="n">ESP_LOGI</span><span class="p">(</span><span class="n">TAG</span><span class="p">,</span><span class="w"> </span><span class="s">"PWM 1: 0x%04x"</span><span class="p">,</span><span class="w"> </span><span class="n">buf</span><span class="o">-></span><span class="n">motor1_rpm_pwm</span><span class="p">);</span>
|
|
<span class="p">}</span>
|
|
</pre>
|
|
</div>
|
|
</div>
|
|
</section>
|
|
<section id="schematic">
|
|
<h3>
|
|
Schematic
|
|
<a class="headerlink" href="#schematic" title="Link to this heading">
|
|
¶
|
|
</a>
|
|
</h3>
|
|
<img alt="_images/ESP-IDF_Robot_schematic.png" src="_images/ESP-IDF_Robot_schematic.png"/>
|
|
</section>
|
|
</section>
|
|
<span id="document-data">
|
|
</span>
|
|
<section id="data-structs">
|
|
<h2>
|
|
DATA STRUCTS
|
|
<a class="headerlink" href="#data-structs" title="Link to this heading">
|
|
¶
|
|
</a>
|
|
</h2>
|
|
<p>
|
|
The struct serves as the data payload for sending control signals from the transmitting device to the receiver using ESP-NOW.
|
|
In addition, it may contain additional data such as telemetry, battery status, etc. The
|
|
<em>
|
|
sensors_data_t
|
|
</em>
|
|
struct encapsulates all control commands and sensor states
|
|
relevant to the vehicle’s operation. It’s intended to be sent from a transmitting device (like a remote control) to a receiver
|
|
(such as a microcontroller on board of the vehicle).
|
|
</p>
|
|
<div class="highlight-c notranslate">
|
|
<div class="highlight">
|
|
<pre><span></span><span class="k">typedef</span><span class="w"> </span><span class="k">struct</span><span class="w"> </span><span class="p">{</span>
|
|
<span class="w"> </span><span class="kt">int</span><span class="w"> </span><span class="n">x_axis</span><span class="p">;</span><span class="w"> </span><span class="c1">// Joystick x-position</span>
|
|
<span class="w"> </span><span class="kt">int</span><span class="w"> </span><span class="n">y_axis</span><span class="p">;</span><span class="w"> </span><span class="c1">// Joystick y-position</span>
|
|
<span class="w"> </span><span class="kt">bool</span><span class="w"> </span><span class="n">nav_bttn</span><span class="p">;</span><span class="w"> </span><span class="c1">// Joystick push button</span>
|
|
<span class="w"> </span><span class="kt">bool</span><span class="w"> </span><span class="n">led</span><span class="p">;</span><span class="w"> </span><span class="c1">// LED ON/OFF state</span>
|
|
<span class="w"> </span><span class="kt">uint8_t</span><span class="w"> </span><span class="n">motor1_rpm_pwm</span><span class="p">;</span><span class="w"> </span><span class="c1">// PWMs for 4 DC motors</span>
|
|
<span class="w"> </span><span class="kt">uint8_t</span><span class="w"> </span><span class="n">motor2_rpm_pwm</span><span class="p">;</span>
|
|
<span class="w"> </span><span class="kt">uint8_t</span><span class="w"> </span><span class="n">motor3_rpm_pwm</span><span class="p">;</span>
|
|
<span class="w"> </span><span class="kt">uint8_t</span><span class="w"> </span><span class="n">motor4_rpm_pwm</span><span class="p">;</span>
|
|
<span class="p">}</span><span class="w"> </span><span class="n">__attribute__</span><span class="p">((</span><span class="n">packed</span><span class="p">))</span><span class="w"> </span><span class="n">sensors_data_t</span><span class="p">;</span>
|
|
</pre>
|
|
</div>
|
|
</div>
|
|
<div class="highlight-c notranslate">
|
|
<div class="highlight">
|
|
<pre><span></span><span class="k">struct</span><span class="w"> </span><span class="nc">motors_rpm</span><span class="w"> </span><span class="p">{</span>
|
|
<span class="w"> </span><span class="kt">int</span><span class="w"> </span><span class="n">motor1_rpm_pwm</span><span class="p">;</span>
|
|
<span class="w"> </span><span class="kt">int</span><span class="w"> </span><span class="n">motor2_rpm_pwm</span><span class="p">;</span>
|
|
<span class="w"> </span><span class="kt">int</span><span class="w"> </span><span class="n">motor3_rpm_pwm</span><span class="p">;</span>
|
|
<span class="w"> </span><span class="kt">int</span><span class="w"> </span><span class="n">motor4_rpm_pwm</span><span class="p">;</span>
|
|
<span class="p">};</span>
|
|
</pre>
|
|
</div>
|
|
</div>
|
|
<p>
|
|
When used with communication protocols like ESP-NOW, this struct is
|
|
<strong>
|
|
encoded
|
|
</strong>
|
|
into a byte stream, then
|
|
<strong>
|
|
transmitted
|
|
</strong>
|
|
at regular intervals or in response to user input, and finally
|
|
<strong>
|
|
decoded
|
|
</strong>
|
|
on the receiving end to control hardware.
|
|
</p>
|
|
<div class="admonition-what-is-struct admonition">
|
|
<p class="admonition-title">
|
|
What is struct?
|
|
</p>
|
|
<p>
|
|
In C programming, a struct (short for structure) is a user-defined data type that lets you group multiple variables of different types together under a
|
|
single name. It’s like a container that holds related information — perfect for organizing data that logically belongs together. Structs are especially
|
|
powerful in systems programming, embedded projects, and when dealing with raw binary data — like parsing sensor input or transmitting control packets over
|
|
ESP-NOW.
|
|
</p>
|
|
</div>
|
|
<section id="data-payload">
|
|
<h3>
|
|
Data Payload
|
|
<a class="headerlink" href="#data-payload" title="Link to this heading">
|
|
¶
|
|
</a>
|
|
</h3>
|
|
<p>
|
|
<em>
|
|
x_axis
|
|
</em>
|
|
and
|
|
<em>
|
|
y_axis
|
|
</em>
|
|
fields capture analog input from a joystick, determining direction and speed.
|
|
<em>
|
|
nav_bttn
|
|
</em>
|
|
represents a joystick push-button.
|
|
</p>
|
|
<p>
|
|
<em>
|
|
led
|
|
</em>
|
|
allows the transmitter to toggle an onboard LED and is used for status indication (e.g. pairing, battery warning, etc).
|
|
</p>
|
|
<p>
|
|
<em>
|
|
motor1_rpm_pwm
|
|
</em>
|
|
to
|
|
<em>
|
|
motor4_rpm_pwm
|
|
</em>
|
|
provide individual PWM signals to four DC motors.
|
|
This enables fine-grained speed control, supports differential drive configurations, and even allows for maneuvering in multi-directional platforms like omni-wheel robots.
|
|
</p>
|
|
<section id="why-use-attribute-packed">
|
|
<h4>
|
|
Why use __attribute((packed))?
|
|
<a class="headerlink" href="#why-use-attribute-packed" title="Link to this heading">
|
|
¶
|
|
</a>
|
|
</h4>
|
|
<p>
|
|
ESP-NOW uses fixed-size data packets (up to 250 bytes). The
|
|
<em>
|
|
__attribute__((packed))
|
|
</em>
|
|
removes compiler-added padding for precise byte alignment.
|
|
</p>
|
|
<p>
|
|
As
|
|
<em>
|
|
packed
|
|
</em>
|
|
attribute tells the compiler not to add any padding between fields in memory, this makes the struct:
|
|
</p>
|
|
<blockquote>
|
|
<div>
|
|
<ul class="simple">
|
|
<li>
|
|
<p>
|
|
Compact
|
|
</p>
|
|
</li>
|
|
<li>
|
|
<p>
|
|
Predictable for serialization over protocols like UART or ESP-NOW
|
|
</p>
|
|
</li>
|
|
<li>
|
|
<p>
|
|
Ideal for low-latency transmission in embedded systems
|
|
</p>
|
|
</li>
|
|
</ul>
|
|
</div>
|
|
</blockquote>
|
|
<p>
|
|
This ensures the receiver interprets the exact byte layout you expect, minimizing bandwidth and maximizing compatibility across platforms.
|
|
</p>
|
|
</section>
|
|
</section>
|
|
</section>
|
|
<span id="document-transmitter">
|
|
</span>
|
|
<section id="transmitter">
|
|
<h2>
|
|
TRANSMITTER
|
|
<a class="headerlink" href="#transmitter" title="Link to this heading">
|
|
¶
|
|
</a>
|
|
</h2>
|
|
<section id="configuration-variables">
|
|
<h3>
|
|
Configuration Variables
|
|
<a class="headerlink" href="#configuration-variables" title="Link to this heading">
|
|
¶
|
|
</a>
|
|
</h3>
|
|
<div class="highlight-c notranslate">
|
|
<div class="highlight">
|
|
<pre><span></span><span class="kt">uint8_t</span><span class="w"> </span><span class="n">receiver_mac</span><span class="p">[</span><span class="n">ESP_NOW_ETH_ALEN</span><span class="p">]</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="p">{</span><span class="mh">0xe4</span><span class="p">,</span><span class="w"> </span><span class="mh">0xb0</span><span class="p">,</span><span class="w"> </span><span class="mh">0x63</span><span class="p">,</span><span class="w"> </span><span class="mh">0x17</span><span class="p">,</span><span class="w"> </span><span class="mh">0x9e</span><span class="p">,</span><span class="w"> </span><span class="mh">0x44</span><span class="p">};</span>
|
|
|
|
<span class="k">typedef</span><span class="w"> </span><span class="k">struct</span><span class="w"> </span><span class="p">{</span>
|
|
<span class="w"> </span><span class="kt">int</span><span class="w"> </span><span class="n">x_axis</span><span class="p">;</span><span class="w"> </span><span class="c1">// Joystick x-position</span>
|
|
<span class="w"> </span><span class="kt">int</span><span class="w"> </span><span class="n">y_axis</span><span class="p">;</span><span class="w"> </span><span class="c1">// Joystick y-position</span>
|
|
<span class="w"> </span><span class="kt">bool</span><span class="w"> </span><span class="n">nav_btn</span><span class="p">;</span><span class="w"> </span><span class="c1">// Joystick push button</span>
|
|
<span class="w"> </span><span class="kt">bool</span><span class="w"> </span><span class="n">led</span><span class="p">;</span><span class="w"> </span><span class="c1">// LED ON/OFF state</span>
|
|
<span class="w"> </span><span class="kt">uint8_t</span><span class="w"> </span><span class="n">motor1_rpm_pwm</span><span class="p">;</span><span class="w"> </span><span class="c1">// PWMs for each DC motor</span>
|
|
<span class="w"> </span><span class="kt">uint8_t</span><span class="w"> </span><span class="n">motor2_rpm_pwm</span><span class="p">;</span>
|
|
<span class="w"> </span><span class="kt">uint8_t</span><span class="w"> </span><span class="n">motor3_rpm_pwm</span><span class="p">;</span>
|
|
<span class="w"> </span><span class="kt">uint8_t</span><span class="w"> </span><span class="n">motor4_rpm_pwm</span><span class="p">;</span>
|
|
<span class="p">}</span><span class="w"> </span><span class="n">__attribute__</span><span class="p">((</span><span class="n">packed</span><span class="p">))</span><span class="w"> </span><span class="n">sensors_data_t</span><span class="p">;</span>
|
|
</pre>
|
|
</div>
|
|
</div>
|
|
</section>
|
|
<section id="reading-joystick-x-and-y-axis-values">
|
|
<h3>
|
|
Reading Joystick x- and y- Axis Values
|
|
<a class="headerlink" href="#reading-joystick-x-and-y-axis-values" title="Link to this heading">
|
|
¶
|
|
</a>
|
|
</h3>
|
|
</section>
|
|
<section id="sending-ecapsulating-data">
|
|
<h3>
|
|
Sending & Ecapsulating Data
|
|
<a class="headerlink" href="#sending-ecapsulating-data" title="Link to this heading">
|
|
¶
|
|
</a>
|
|
</h3>
|
|
<div class="highlight-c notranslate">
|
|
<div class="highlight">
|
|
<pre><span></span><span class="kt">void</span><span class="w"> </span><span class="nf">sendData</span><span class="w"> </span><span class="p">(</span><span class="kt">void</span><span class="p">)</span><span class="w"> </span><span class="p">{</span>
|
|
|
|
<span class="w"> </span><span class="p">...</span><span class="w"> </span><span class="p">...</span><span class="w"> </span><span class="p">...</span>
|
|
<span class="w"> </span><span class="p">...</span><span class="w"> </span><span class="p">...</span><span class="w"> </span><span class="p">...</span>
|
|
|
|
<span class="w"> </span><span class="n">buffer</span><span class="p">.</span><span class="n">x_axis</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">x_axis</span><span class="p">;</span>
|
|
<span class="w"> </span><span class="n">buffer</span><span class="p">.</span><span class="n">y_axis</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">y_axis</span><span class="p">;</span>
|
|
|
|
<span class="w"> </span><span class="c1">// Call ESP-NOW function to send data (MAC address of receiver, pointer to the memory holding data & data length)</span>
|
|
<span class="w"> </span><span class="kt">uint8_t</span><span class="w"> </span><span class="n">result</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">esp_now_send</span><span class="p">((</span><span class="kt">uint8_t</span><span class="o">*</span><span class="p">)</span><span class="n">receiver_mac</span><span class="p">,</span><span class="w"> </span><span class="p">(</span><span class="kt">uint8_t</span><span class="w"> </span><span class="o">*</span><span class="p">)</span><span class="o">&</span><span class="n">buffer</span><span class="p">,</span><span class="w"> </span><span class="k">sizeof</span><span class="p">(</span><span class="n">buffer</span><span class="p">));</span>
|
|
|
|
<span class="w"> </span><span class="p">...</span><span class="w"> </span><span class="p">...</span><span class="w"> </span><span class="p">...</span>
|
|
<span class="w"> </span><span class="p">...</span><span class="w"> </span><span class="p">...</span><span class="w"> </span><span class="p">...</span>
|
|
<span class="p">}</span>
|
|
</pre>
|
|
</div>
|
|
</div>
|
|
</section>
|
|
<section id="main-function">
|
|
<h3>
|
|
Main Function
|
|
<a class="headerlink" href="#main-function" title="Link to this heading">
|
|
¶
|
|
</a>
|
|
</h3>
|
|
<div class="highlight-c notranslate">
|
|
<div class="highlight">
|
|
<pre><span></span><span class="cp">#include</span><span class="w"> </span><span class="cpf">"freertos/FreeRTOS.h"</span>
|
|
<span class="cp">#include</span><span class="w"> </span><span class="cpf">"nvs_flash.h"</span>
|
|
<span class="cp">#include</span><span class="w"> </span><span class="cpf">"esp_err.h"</span>
|
|
|
|
<span class="p">...</span><span class="w"> </span><span class="p">...</span><span class="w"> </span><span class="p">...</span>
|
|
<span class="p">...</span><span class="w"> </span><span class="p">...</span><span class="w"> </span><span class="p">...</span>
|
|
|
|
<span class="kt">void</span><span class="w"> </span><span class="n">app_main</span><span class="p">(</span><span class="kt">void</span><span class="p">)</span><span class="w"> </span><span class="p">{</span>
|
|
|
|
<span class="w"> </span><span class="p">...</span><span class="w"> </span><span class="p">...</span><span class="w"> </span><span class="p">...</span>
|
|
<span class="w"> </span><span class="p">...</span><span class="w"> </span><span class="p">...</span><span class="w"> </span><span class="p">...</span>
|
|
|
|
<span class="w"> </span><span class="c1">// Initialize internal temperature sensor</span>
|
|
<span class="w"> </span><span class="n">chip_sensor_init</span><span class="p">();</span>
|
|
|
|
<span class="w"> </span><span class="c1">// Initialize NVS</span>
|
|
<span class="w"> </span><span class="n">esp_err_t</span><span class="w"> </span><span class="n">ret</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">nvs_flash_init</span><span class="p">();</span>
|
|
<span class="w"> </span><span class="k">if</span><span class="w"> </span><span class="p">(</span><span class="n">ret</span><span class="w"> </span><span class="o">==</span><span class="w"> </span><span class="n">ESP_ERR_NVS_NO_FREE_PAGES</span><span class="w"> </span><span class="o">||</span><span class="w"> </span><span class="n">ret</span><span class="w"> </span><span class="o">==</span><span class="w"> </span><span class="n">ESP_ERR_NVS_NEW_VERSION_FOUND</span><span class="p">)</span><span class="w"> </span><span class="p">{</span>
|
|
<span class="w"> </span><span class="n">ESP_ERROR_CHECK</span><span class="p">(</span><span class="w"> </span><span class="n">nvs_flash_erase</span><span class="p">()</span><span class="w"> </span><span class="p">);</span>
|
|
<span class="w"> </span><span class="n">ret</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">nvs_flash_init</span><span class="p">();</span>
|
|
<span class="w"> </span><span class="p">}</span>
|
|
<span class="w"> </span><span class="n">ESP_ERROR_CHECK</span><span class="p">(</span><span class="w"> </span><span class="n">ret</span><span class="w"> </span><span class="p">);</span>
|
|
<span class="w"> </span><span class="n">wifi_init</span><span class="p">();</span>
|
|
<span class="w"> </span><span class="n">joystick_adc_init</span><span class="p">();</span>
|
|
<span class="w"> </span><span class="n">transmission_init</span><span class="p">();</span>
|
|
<span class="w"> </span><span class="n">system_led_init</span><span class="p">();</span>
|
|
|
|
<span class="w"> </span><span class="p">...</span><span class="w"> </span><span class="p">...</span><span class="w"> </span><span class="p">...</span>
|
|
<span class="w"> </span><span class="p">...</span><span class="w"> </span><span class="p">...</span><span class="w"> </span><span class="p">...</span>
|
|
<span class="p">}</span>
|
|
</pre>
|
|
</div>
|
|
</div>
|
|
</section>
|
|
</section>
|
|
<span id="document-receiver">
|
|
</span>
|
|
<section id="receiver">
|
|
<h2>
|
|
RECEIVER
|
|
<a class="headerlink" href="#receiver" title="Link to this heading">
|
|
¶
|
|
</a>
|
|
</h2>
|
|
<section id="configuration-variables">
|
|
<h3>
|
|
Configuration Variables
|
|
<a class="headerlink" href="#configuration-variables" title="Link to this heading">
|
|
¶
|
|
</a>
|
|
</h3>
|
|
<div class="highlight-c notranslate">
|
|
<div class="highlight">
|
|
<pre><span></span><span class="kt">uint8_t</span><span class="w"> </span><span class="n">transmitter_mac</span><span class="p">[</span><span class="n">ESP_NOW_ETH_ALEN</span><span class="p">]</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="p">{</span><span class="mh">0x9C</span><span class="p">,</span><span class="w"> </span><span class="mh">0x9E</span><span class="p">,</span><span class="w"> </span><span class="mh">0x6E</span><span class="p">,</span><span class="w"> </span><span class="mh">0x14</span><span class="p">,</span><span class="w"> </span><span class="mh">0xB5</span><span class="p">,</span><span class="w"> </span><span class="mh">0x54</span><span class="p">};</span>
|
|
|
|
<span class="k">typedef</span><span class="w"> </span><span class="k">struct</span><span class="w"> </span><span class="p">{</span>
|
|
<span class="w"> </span><span class="kt">int</span><span class="w"> </span><span class="n">x_axis</span><span class="p">;</span><span class="w"> </span><span class="c1">// Joystick x-position</span>
|
|
<span class="w"> </span><span class="kt">int</span><span class="w"> </span><span class="n">y_axis</span><span class="p">;</span><span class="w"> </span><span class="c1">// Joystick y-position</span>
|
|
<span class="w"> </span><span class="kt">bool</span><span class="w"> </span><span class="n">nav_bttn</span><span class="p">;</span><span class="w"> </span><span class="c1">// Joystick push button</span>
|
|
<span class="w"> </span><span class="kt">bool</span><span class="w"> </span><span class="n">led</span><span class="p">;</span><span class="w"> </span><span class="c1">// LED ON/OFF state</span>
|
|
<span class="w"> </span><span class="kt">uint8_t</span><span class="w"> </span><span class="n">motor1_rpm_pwm</span><span class="p">;</span><span class="w"> </span><span class="c1">// PWMs for 4 DC motors</span>
|
|
<span class="w"> </span><span class="kt">uint8_t</span><span class="w"> </span><span class="n">motor2_rpm_pwm</span><span class="p">;</span>
|
|
<span class="w"> </span><span class="kt">uint8_t</span><span class="w"> </span><span class="n">motor3_rpm_pwm</span><span class="p">;</span>
|
|
<span class="w"> </span><span class="kt">uint8_t</span><span class="w"> </span><span class="n">motor4_rpm_pwm</span><span class="p">;</span>
|
|
<span class="p">}</span><span class="w"> </span><span class="n">__attribute__</span><span class="p">((</span><span class="n">packed</span><span class="p">))</span><span class="w"> </span><span class="n">sensors_data_t</span><span class="p">;</span>
|
|
</pre>
|
|
</div>
|
|
</div>
|
|
<div class="highlight-c notranslate">
|
|
<div class="highlight">
|
|
<pre><span></span><span class="k">struct</span><span class="w"> </span><span class="nc">motors_rpm</span><span class="w"> </span><span class="p">{</span>
|
|
<span class="w"> </span><span class="kt">int</span><span class="w"> </span><span class="n">motor1_rpm_pwm</span><span class="p">;</span>
|
|
<span class="w"> </span><span class="kt">int</span><span class="w"> </span><span class="n">motor2_rpm_pwm</span><span class="p">;</span>
|
|
<span class="w"> </span><span class="kt">int</span><span class="w"> </span><span class="n">motor3_rpm_pwm</span><span class="p">;</span>
|
|
<span class="w"> </span><span class="kt">int</span><span class="w"> </span><span class="n">motor4_rpm_pwm</span><span class="p">;</span>
|
|
<span class="p">};</span>
|
|
</pre>
|
|
</div>
|
|
</div>
|
|
</section>
|
|
<section id="receiving-extracting-data">
|
|
<h3>
|
|
Receiving & Extracting Data
|
|
<a class="headerlink" href="#receiving-extracting-data" title="Link to this heading">
|
|
¶
|
|
</a>
|
|
</h3>
|
|
<div class="highlight-c notranslate">
|
|
<div class="highlight">
|
|
<pre><span></span><span class="kt">void</span><span class="w"> </span><span class="nf">onDataReceived</span><span class="w"> </span><span class="p">(</span><span class="k">const</span><span class="w"> </span><span class="kt">uint8_t</span><span class="w"> </span><span class="o">*</span><span class="n">mac_addr</span><span class="p">,</span><span class="w"> </span><span class="k">const</span><span class="w"> </span><span class="kt">uint8_t</span><span class="w"> </span><span class="o">*</span><span class="n">data</span><span class="p">,</span><span class="w"> </span><span class="kt">uint8_t</span><span class="w"> </span><span class="n">data_len</span><span class="p">)</span><span class="w"> </span><span class="p">{</span>
|
|
|
|
<span class="w"> </span><span class="p">...</span><span class="w"> </span><span class="p">...</span><span class="w"> </span><span class="p">...</span>
|
|
<span class="w"> </span><span class="p">...</span><span class="w"> </span><span class="p">...</span><span class="w"> </span><span class="p">...</span>
|
|
|
|
<span class="w"> </span><span class="n">ESP_LOGI</span><span class="p">(</span><span class="n">TAG</span><span class="p">,</span><span class="w"> </span><span class="s">"Data received from: %02x:%02x:%02x:%02x:%02x:%02x, len=%d"</span><span class="p">,</span><span class="w"> </span><span class="n">mac_addr</span><span class="p">[</span><span class="mi">0</span><span class="p">],</span><span class="w"> </span><span class="n">mac_addr</span><span class="p">[</span><span class="mi">1</span><span class="p">],</span><span class="w"> </span><span class="n">mac_addr</span><span class="p">[</span><span class="mi">2</span><span class="p">],</span><span class="w"> </span><span class="n">mac_addr</span><span class="p">[</span><span class="mi">3</span><span class="p">],</span><span class="w"> </span><span class="n">mac_addr</span><span class="p">[</span><span class="mi">4</span><span class="p">],</span><span class="w"> </span><span class="n">mac_addr</span><span class="p">[</span><span class="mi">5</span><span class="p">],</span><span class="w"> </span><span class="n">data_len</span><span class="p">);</span>
|
|
<span class="w"> </span><span class="n">memcpy</span><span class="p">(</span><span class="o">&</span><span class="n">buf</span><span class="p">,</span><span class="w"> </span><span class="n">data</span><span class="p">,</span><span class="w"> </span><span class="k">sizeof</span><span class="p">(</span><span class="n">buf</span><span class="p">));</span>
|
|
|
|
<span class="w"> </span><span class="n">x_axis</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">buf</span><span class="p">.</span><span class="n">x_axis</span><span class="p">;</span>
|
|
<span class="w"> </span><span class="n">y_axis</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">buf</span><span class="p">.</span><span class="n">y_axis</span><span class="p">;</span>
|
|
|
|
<span class="w"> </span><span class="p">...</span><span class="w"> </span><span class="p">...</span><span class="w"> </span><span class="p">...</span>
|
|
<span class="w"> </span><span class="p">...</span><span class="w"> </span><span class="p">...</span><span class="w"> </span><span class="p">...</span>
|
|
<span class="p">}</span>
|
|
</pre>
|
|
</div>
|
|
</div>
|
|
</section>
|
|
<section id="main-function">
|
|
<h3>
|
|
Main Function
|
|
<a class="headerlink" href="#main-function" title="Link to this heading">
|
|
¶
|
|
</a>
|
|
</h3>
|
|
<div class="highlight-c notranslate">
|
|
<div class="highlight">
|
|
<pre><span></span><span class="cp">#include</span><span class="w"> </span><span class="cpf"><string.h></span>
|
|
<span class="cp">#include</span><span class="w"> </span><span class="cpf">"freertos/FreeRTOS.h"</span>
|
|
<span class="cp">#include</span><span class="w"> </span><span class="cpf">"nvs_flash.h"</span>
|
|
<span class="cp">#include</span><span class="w"> </span><span class="cpf">"esp_err.h"</span>
|
|
|
|
<span class="p">...</span><span class="w"> </span><span class="p">...</span><span class="w"> </span><span class="p">...</span>
|
|
<span class="p">...</span><span class="w"> </span><span class="p">...</span><span class="w"> </span><span class="p">...</span>
|
|
|
|
<span class="kt">void</span><span class="w"> </span><span class="n">app_main</span><span class="p">(</span><span class="kt">void</span><span class="p">)</span><span class="w"> </span><span class="p">{</span>
|
|
|
|
<span class="w"> </span><span class="p">...</span><span class="w"> </span><span class="p">...</span><span class="w"> </span><span class="p">...</span>
|
|
<span class="w"> </span><span class="p">...</span><span class="w"> </span><span class="p">...</span><span class="w"> </span><span class="p">...</span>
|
|
|
|
<span class="w"> </span><span class="c1">// Initialize NVS</span>
|
|
<span class="w"> </span><span class="n">esp_err_t</span><span class="w"> </span><span class="n">ret</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">nvs_flash_init</span><span class="p">();</span>
|
|
<span class="w"> </span><span class="k">if</span><span class="w"> </span><span class="p">(</span><span class="n">ret</span><span class="w"> </span><span class="o">==</span><span class="w"> </span><span class="n">ESP_ERR_NVS_NO_FREE_PAGES</span><span class="w"> </span><span class="o">||</span>
|
|
<span class="w"> </span><span class="n">ret</span><span class="w"> </span><span class="o">==</span><span class="w"> </span><span class="n">ESP_ERR_NVS_NEW_VERSION_FOUND</span><span class="p">)</span><span class="w"> </span><span class="p">{</span>
|
|
<span class="w"> </span><span class="n">ESP_ERROR_CHECK</span><span class="p">(</span><span class="w"> </span><span class="n">nvs_flash_erase</span><span class="p">()</span><span class="w"> </span><span class="p">);</span>
|
|
<span class="w"> </span><span class="n">ret</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">nvs_flash_init</span><span class="p">();</span>
|
|
<span class="w"> </span><span class="p">}</span>
|
|
|
|
<span class="w"> </span><span class="n">ESP_ERROR_CHECK</span><span class="p">(</span><span class="w"> </span><span class="n">ret</span><span class="w"> </span><span class="p">);</span>
|
|
<span class="w"> </span><span class="n">wifi_init</span><span class="p">();</span>
|
|
<span class="w"> </span><span class="n">ESP_ERROR_CHECK</span><span class="p">(</span><span class="n">esp_now_init</span><span class="p">());</span>
|
|
|
|
<span class="w"> </span><span class="n">esp_now_peer_info_t</span><span class="w"> </span><span class="n">transmitterInfo</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="p">{</span><span class="mi">0</span><span class="p">};</span>
|
|
<span class="w"> </span><span class="n">memcpy</span><span class="p">(</span><span class="n">transmitterInfo</span><span class="p">.</span><span class="n">peer_addr</span><span class="p">,</span><span class="w"> </span><span class="n">transmitter_mac</span><span class="p">,</span><span class="w"> </span><span class="n">ESP_NOW_ETH_ALEN</span><span class="p">);</span>
|
|
<span class="w"> </span><span class="n">transmitterInfo</span><span class="p">.</span><span class="n">channel</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="mi">0</span><span class="p">;</span><span class="w"> </span><span class="c1">// Current WiFi channel</span>
|
|
<span class="w"> </span><span class="n">transmitterInfo</span><span class="p">.</span><span class="n">ifidx</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">ESP_IF_WIFI_STA</span><span class="p">;</span>
|
|
<span class="w"> </span><span class="n">transmitterInfo</span><span class="p">.</span><span class="n">encrypt</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="nb">false</span><span class="p">;</span>
|
|
<span class="w"> </span><span class="n">ESP_ERROR_CHECK</span><span class="p">(</span><span class="n">esp_now_add_peer</span><span class="p">(</span><span class="o">&</span><span class="n">transmitterInfo</span><span class="p">));</span>
|
|
|
|
<span class="w"> </span><span class="n">ESP_ERROR_CHECK</span><span class="p">(</span><span class="n">esp_now_register_recv_cb</span><span class="p">((</span><span class="kt">void</span><span class="o">*</span><span class="p">)</span><span class="n">onDataReceived</span><span class="p">));</span>
|
|
|
|
<span class="w"> </span><span class="n">system_led_init</span><span class="p">();</span>
|
|
|
|
<span class="w"> </span><span class="p">...</span><span class="w"> </span><span class="p">...</span><span class="w"> </span><span class="p">...</span>
|
|
<span class="w"> </span><span class="p">...</span><span class="w"> </span><span class="p">...</span><span class="w"> </span><span class="p">...</span>
|
|
<span class="p">}</span>
|
|
</pre>
|
|
</div>
|
|
</div>
|
|
</section>
|
|
</section>
|
|
<span id="document-progress">
|
|
</span>
|
|
<section id="work-in-progress-walk-through">
|
|
<h2>
|
|
WORK-IN-PROGRESS WALK THROUGH
|
|
<a class="headerlink" href="#work-in-progress-walk-through" title="Link to this heading">
|
|
¶
|
|
</a>
|
|
</h2>
|
|
<section id="finished-work">
|
|
<h3>
|
|
Finished Work
|
|
<a class="headerlink" href="#finished-work" title="Link to this heading">
|
|
¶
|
|
</a>
|
|
</h3>
|
|
<img alt="_images/ESP-IDF_Robot.jpg" src="_images/ESP-IDF_Robot.jpg"/>
|
|
</section>
|
|
<section id="chassis">
|
|
<h3>
|
|
Chassis
|
|
<a class="headerlink" href="#chassis" title="Link to this heading">
|
|
¶
|
|
</a>
|
|
</h3>
|
|
<figure class="align-center" id="id1">
|
|
<a class="reference internal image-reference" href="_images/chassi-progress_002d.jpg">
|
|
<img alt="_images/chassi-progress_002d.jpg" src="_images/chassi-progress_002d.jpg" style="height: 300px;"/>
|
|
</a>
|
|
<figcaption>
|
|
<p>
|
|
<span class="caption-text">
|
|
Completed chassis with only DC motor controllers installed.
|
|
</span>
|
|
<a class="headerlink" href="#id1" title="Link to this image">
|
|
¶
|
|
</a>
|
|
</p>
|
|
</figcaption>
|
|
</figure>
|
|
</section>
|
|
<section id="wiring">
|
|
<h3>
|
|
Wiring
|
|
<a class="headerlink" href="#wiring" title="Link to this heading">
|
|
¶
|
|
</a>
|
|
</h3>
|
|
<figure class="align-center" id="id2">
|
|
<a class="reference internal image-reference" href="_images/chassi-progress_003a.jpg">
|
|
<img alt="_images/chassi-progress_003a.jpg" src="_images/chassi-progress_003a.jpg" style="height: 750px;"/>
|
|
</a>
|
|
<figcaption>
|
|
<p>
|
|
<span class="caption-text">
|
|
Completed wiring.
|
|
</span>
|
|
<a class="headerlink" href="#id2" title="Link to this image">
|
|
¶
|
|
</a>
|
|
</p>
|
|
</figcaption>
|
|
</figure>
|
|
</section>
|
|
<section id="motor-wires-harness">
|
|
<h3>
|
|
Motor Wires Harness
|
|
<a class="headerlink" href="#motor-wires-harness" title="Link to this heading">
|
|
¶
|
|
</a>
|
|
</h3>
|
|
<figure class="align-center" id="id3">
|
|
<img alt="_images/motors-wiring-harness-001.jpg" src="_images/motors-wiring-harness-001.jpg"/>
|
|
<figcaption>
|
|
<p>
|
|
<span class="caption-text">
|
|
DC Motors wires secured inside harnes.
|
|
</span>
|
|
<a class="headerlink" href="#id3" title="Link to this image">
|
|
¶
|
|
</a>
|
|
</p>
|
|
</figcaption>
|
|
</figure>
|
|
</section>
|
|
</section>
|
|
<span id="document-references">
|
|
</span>
|
|
<section id="references">
|
|
<h2>
|
|
REFERENCES
|
|
<a class="headerlink" href="#references" title="Link to this heading">
|
|
¶
|
|
</a>
|
|
</h2>
|
|
<section id="github">
|
|
<h3>
|
|
GitHub
|
|
<a class="headerlink" href="#github" title="Link to this heading">
|
|
¶
|
|
</a>
|
|
</h3>
|
|
<p>
|
|
Complete source
|
|
<a class="reference external" href="https://github.com/alexandrebobkov/ESP-Nodes/blob/main/ESP-IDF_Robot/README.md">
|
|
code
|
|
</a>
|
|
with README.md file:
|
|
<a class="reference external" href="https://github.com/alexandrebobkov/ESP-Nodes/blob/main/ESP-IDF_Robot/README.md">
|
|
https://github.com/alexandrebobkov/ESP-Nodes/blob/main/ESP-IDF_Robot/README.md
|
|
</a>
|
|
</p>
|
|
<p>
|
|
KiCAd
|
|
<a class="reference external" href="https://github.com/alexandrebobkov/ESP32-C3_Breadboard-Adapter">
|
|
Schematic
|
|
</a>
|
|
and PCB design:
|
|
<a class="reference external" href="https://github.com/alexandrebobkov/ESP32-C3_Breadboard-Adapter">
|
|
https://github.com/alexandrebobkov/ESP32-C3_Breadboard-Adapter
|
|
</a>
|
|
</p>
|
|
</section>
|
|
</section>
|
|
</div>
|
|
</section>
|
|
<div class="clearer">
|
|
</div>
|
|
</div>
|
|
</div>
|
|
</div>
|
|
<div class="clearer">
|
|
</div>
|
|
</div>
|
|
<article id="back-cover">
|
|
<div class="container">
|
|
<div class="back-cover-footer">
|
|
<p>
|
|
© Copyright 2025, Alexander B.
|
|
</p>
|
|
<p>
|
|
Created using
|
|
<a href="http://sphinx-doc.org/">
|
|
Sphinx
|
|
</a>
|
|
8.2.3.
|
|
</p>
|
|
</div>
|
|
</div>
|
|
</article>
|
|
</body>
|
|
</html>
|