basic_polling.ino

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/**
 * @~English
 * @file decoder/ble_serial_module/basic_polling/basic_polling.ino
 * @example decoder/ble_serial_module/basic_polling/basic_polling.ino
 * @brief The demonstration regularly prints the status of all buttons and joystick values using a basic polling method.
 * @details This example first sends AT commands to connect to a target device, then enters a simple polling loop. Every 30
 *          milliseconds, it prints the current state of all buttons (pressed/released) and the raw analog values (0‑255) of
 *          both joysticks. It showcases the fundamental usage of `gamepad::input::Tracker[Button]` for discrete button queries
 *          and `gamepad::input::Tracker[Axis]` for continuous joystick readings.
 * @note This example uses a simple timing mechanism (`millis()`) to print at a fixed interval, which is suitable for
 *       monitoring or logging. For real‑time control, ensure `Update()` is called as frequently as possible without blocking
 *       delays.
 * @see gamepad::codec::Decoder::Update
 */
/**
 * @~Chinese
 * @file decoder/ble_serial_module/basic_polling/basic_polling.ino
 * @example decoder/ble_serial_module/basic_polling/basic_polling.ino
 * @brief 演示通过基本轮询方式定期打印所有按钮状态与摇杆值。
 * @details 本示例先通过 AT 指令连接到指定的蓝牙设备，然后进入轮询循环。
 *          每隔 30 毫秒，它会打印所有按钮的当前状态（按下/弹起）以及两个摇杆的原始模拟值（0‑255）。
 *          它展示了 `gamepad::input::Tracker[Button]` 用于离散按钮查询和 `gamepad::input::Tracker[Axis]`
 *          用于连续摇杆读取的基本用法。
 * @note 本示例使用简单的定时机制（`millis()`）以固定间隔打印，适用于状态监控或日志记录。
 *       对于实时控制应用，请确保尽可能频繁地调用 `Update()` 且无阻塞延时。
 * @see gamepad::codec::Decoder::Update
 */
 
#include <SoftwareSerial.h>
 
#include "gamepad_codec_decoder.h"
 
/**
 * IMPORTANT:
 * This using directive is REQUIRED to directly access `Button` and `Axis`.
 * Without it, you must write the fully qualified names:
 *   gamepad::input::Button::kUp
 *   gamepad::input::Axis::kLeftStickX
 * Forgetting this line will cause compile errors when using Button or Axis.
 */
/**
 * 重要：
 * 必须使用该命名空间，否则无法直接访问 `Button` 和 `Axis`。
 * 如果没有这一行，就必须写成完整限定名：
 *   gamepad::input::Button::kUp
 *   gamepad::input::Axis::kLeftStickX
 * 忘记引入命名空间会导致编译失败。
 */
using namespace gamepad::input;
 
namespace {
// Debug serial port pin definitions.
// Connect external serial port tools to these pins to view debug output.
// 调试串口引脚定义。
// 将外部串口工具连接到这些引脚以查看调试输出。
constexpr uint8_t kDebugSerialRxPin = 6;  // RX pin for debug output | 调试输出接收引脚
constexpr uint8_t kDebugSerialTxPin = 5;  // TX pin for debug output | 调试输出发送引脚
 
// Replace with your target device's Bluetooth device address.
// 替换为目标设备的 Bluetooth device address。
const String kBluetoothDeviceAddress = "16:00:00:00:03:05";
 
// The serial port baud rate for communication with the Bluetooth module (please refer to the module data manual, replace with
// the corresponding baud rate for the module).
// 与蓝牙模块通信的串口波特率（请查阅模块数据手册，替换为模块对应的波特率）。
constexpr uint32_t kBluetoothModuleSerialBaudRate = 115200;
 
// The serial instance passed in by the decoder here is the same as the one passed in Connect().
// 此处解码器传入的串口实例，与 Connect() 中传入的为同一个串口实例。
gamepad::codec::Decoder g_decoder(Serial);
 
// A soft serial port used for debugging output.
// 用于调试输出的软串口。
SoftwareSerial g_debug_serial(kDebugSerialRxPin, kDebugSerialTxPin);
 
/**
 * @~English
 * @brief Send AT commands to the Bluetooth module to establish a BLE connection.
 * @details Executes a sequence of AT commands to configure the Bluetooth module as master and connect to the target device
 *          at the specified MAC address.
 *          Command order: AT+DISCON → AT+RESET → AT+ECHO=0 → AT+ROLE=0 → AT+AUTOCON=0 → AT+CON=<mac>.
 * @param[in] bluetooth_stream Stream connected to the Bluetooth module.
 *                             Note: This must be the same Stream instance that is passed to the decoder
 *                             (e.g., Serial), as the decoder reads incoming data from this same serial port.
 * @param[in] bluetooth_device_address MAC address of the target device in format "XX:XX:XX:XX:XX:XX".
 */
/**
 * @~Chinese
 * @brief 向蓝牙模块发送 AT 指令以建立 BLE 连接。
 * @details 依次执行 AT 指令序列，将蓝牙模块配置为主机模式并连接到指定 MAC 地址的目标设备。
 *          指令顺序：AT+DISCON → AT+RESET → AT+ECHO=0 → AT+ROLE=0 → AT+AUTOCON=0 → AT+CON=<mac>。
 * @param[in] bluetooth_stream 连接蓝牙模块的 Stream 对象。
 *                             注意：此对象必须与传入解码器的 Stream 是同一个实例（如 Serial），
 *                             因为解码器正是从这同一个串口读取手柄发来的数据。
 * @param[in] bluetooth_device_address 目标设备的 MAC 地址，格式为 "XX:XX:XX:XX:XX:XX"。
 */
void Connect(Stream &bluetooth_stream, const String &bluetooth_device_address) {
  if (bluetooth_device_address.length() != 17 || bluetooth_device_address[2] != ':' || bluetooth_device_address[5] != ':' ||
      bluetooth_device_address[8] != ':' || bluetooth_device_address[11] != ':' || bluetooth_device_address[14] != ':') {
    g_debug_serial.println("Error: Invalid MAC address format. Expected: XX:XX:XX:XX:XX:XX");
    while (true);
  }
 
  g_debug_serial.print("Start to connect ");
  g_debug_serial.println(kBluetoothDeviceAddress);
 
  // The module may be in a connected state. Send the disconnection command first to ensure the module is in an unconnected
  // state.
  // 模块可能处于连接状态，先发送断开指令，确保模块是未连接状态。
  bluetooth_stream.println("AT+DISCON");
  delay(100);
 
  // Software reset BLE chip, clear all pairing and configuration data.
  // 软件复位蓝牙芯片，清除所有配对和配置数据。
  bluetooth_stream.println("AT+RESET");
  delay(100);
 
  // Close AT information echo.
  // 关闭AT信息回显。
  bluetooth_stream.println("AT+ECHO=0");
  delay(100);
 
  // Set the module to host mode so that it can actively connect to the BLE of the slave device.
  // 设置模块为主机模式，使其能够主动连接从机蓝牙。
  bluetooth_stream.println("AT+ROLE=0");
  delay(100);
 
  // Disable the module's automatic Bluetooth connection mode.
  // 关闭模块的蓝牙自动连接模式。
  bluetooth_stream.println("AT+AUTOCON=0");
  delay(100);
 
  // Initiate BLE connection with the slave using the specified MAC address.
  // 使用指定的MAC地址发起与从机蓝牙连接。
  bluetooth_stream.print("AT+CON=");
  bluetooth_stream.println(bluetooth_device_address);
  delay(100);
 
  g_debug_serial.println("Connected");
}
}  // namespace
 
void setup() {
  g_debug_serial.begin(115200);
 
  Serial.begin(kBluetoothModuleSerialBaudRate);
 
  Connect(Serial, kBluetoothDeviceAddress);
}
 
void loop() {
  // ==========================================================================
  // 🔴 CRITICAL: Call Update() as frequently as possible in loop()
  // ==========================================================================
  // • Update() processes incoming Bluetooth packets from the gamepad.
  // • Any delay(...) or long blocking code WILL cause:
  //     - Packet loss
  //     - Input lag
  //     - Unstable connection
  //
  // • For real-time control, call Update() every loop iteration
  //   without any blocking operations
  //
  // 🔴【重要】Update() 必须在 loop() 中尽可能高频调用
  // • Update() 负责处理来自手柄的蓝牙数据包。
  // • 任何形式的 delay 或阻塞代码都会导致：
  //     - 数据丢失
  //     - 响应延迟
  //     - 连接不稳定
  //
  // • 实时控制应用中，必须每轮循环都调用 Update()，不可阻塞
  // ==========================================================================
  const Tracker &it = g_decoder.Update();
  // ==========================================================================
  // Tracker: Gamepad Input Snapshot & Change Engine
  // ==========================================================================
  // • Returned by Update()
  // • Maintains previous and current input snapshots
  // • Enables edge detection and delta detection
  //
  // Tracker 由 Update() 返回
  // 内部保存上一帧和当前帧的输入数据
  // 支持边沿检测和差值检测
  //
  // 📚 https://codexpad.github.io/gamepad_input_arduino_lib/
  // ==========================================================================
 
  static uint32_t s_print_time = 0;
  if (s_print_time != 0 && s_print_time + 30 > millis()) {
    return;
  }
 
  s_print_time = millis();
 
  // ------------------------------------------------------------------
  // Button states (boolean -> uint)
  // operator[] returns bool:
  //   true  = pressed
  //   false = released
  //
  // 按钮状态（bool 类型，打印时被隐式转换为 1 / 0）
  // true  : 按下
  // false : 弹起
  // ------------------------------------------------------------------
  g_debug_serial.print("Up:");
  g_debug_serial.print(it[Button::kUp]);
  g_debug_serial.print(", ");
  g_debug_serial.print("Down:");
  g_debug_serial.print(it[Button::kDown]);
  g_debug_serial.print(", ");
  g_debug_serial.print("Left:");
  g_debug_serial.print(it[Button::kLeft]);
  g_debug_serial.print(", ");
  g_debug_serial.print("Right:");
  g_debug_serial.print(it[Button::kRight]);
  g_debug_serial.print(", ");
  g_debug_serial.print("Square(X):");
  g_debug_serial.print(it[Button::kSquareX]);
  g_debug_serial.print(", ");
  g_debug_serial.print("Triangle(Y):");
  g_debug_serial.print(it[Button::kTriangleY]);
  g_debug_serial.print(", ");
  g_debug_serial.print("Cross(A):");
  g_debug_serial.print(it[Button::kCrossA]);
  g_debug_serial.print(", ");
  g_debug_serial.print("Circle(B):");
  g_debug_serial.print(it[Button::kCircleB]);
  g_debug_serial.print(", ");
  g_debug_serial.print("L1:");
  g_debug_serial.print(it[Button::kL1]);
  g_debug_serial.print(", ");
  g_debug_serial.print("L2:");
  g_debug_serial.print(it[Button::kL2]);
  g_debug_serial.print(", ");
  g_debug_serial.print("L3:");
  g_debug_serial.print(it[Button::kL3]);
  g_debug_serial.print(", ");
  g_debug_serial.print("R1:");
  g_debug_serial.print(it[Button::kR1]);
  g_debug_serial.print(", ");
  g_debug_serial.print("R2:");
  g_debug_serial.print(it[Button::kR2]);
  g_debug_serial.print(", ");
  g_debug_serial.print("R3:");
  g_debug_serial.print(it[Button::kR3]);
  g_debug_serial.print(", ");
  g_debug_serial.print("Select:");
  g_debug_serial.print(it[Button::kSelect]);
  g_debug_serial.print(", ");
  g_debug_serial.print("Start:");
  g_debug_serial.print(it[Button::kStart]);
  g_debug_serial.print(", ");
  g_debug_serial.print("Home:");
  g_debug_serial.print(it[Button::kHome]);
  g_debug_serial.print(", ");
 
  // ------------------------------------------------------------------
  // Joystick axis values (0–255)
  // Center position ≈ 128
  // Smaller → left / down
  // Larger  → right / up
  //
  // 摇杆轴数据（0～255）
  // 中间值约 128
  // 越小越左 / 下，越大越右 / 上
  // ------------------------------------------------------------------
  g_debug_serial.print("L(X:");
  g_debug_serial.print(it[Axis::kLeftStickX]);
  g_debug_serial.print(", Y:");
  g_debug_serial.print(it[Axis::kLeftStickY]);
  g_debug_serial.print("), R(X:");
  g_debug_serial.print(it[Axis::kRightStickX]);
  g_debug_serial.print(", Y:");
  g_debug_serial.print(it[Axis::kRightStickY]);
  g_debug_serial.println(")");
}