Command & Keep-Alive Library Suite

A collection of lightweight, cross-platform C++ libraries for Arduino and embedded systems that provide structured command parsing, building, and keep-alive connectivity monitoring.

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Repository Structure

.
├── CommandLibary/          # Command parsing & building
│   ├── CmdLib.h           # Core library (header-only)
│   ├── CmdLibTest.cpp     # Unit tests
│   └── README.md          # CmdLib documentation
│
├── KeepAlive/             # Keep-alive / timeout monitoring
│   ├── PingPong.h         # Handler definition
│   ├── PingPong.cpp       # Implementation
│   └── README.md          # PingPong documentation
│
└── README.md              # This file

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Modules Overview

1. CmdLib — Structured Command Protocol

A lightweight, header-only library that provides a standardized format for building and parsing commands with named parameters. Supports both Arduino and standard C++.

Key Features:

• Cross-platform: Arduino (String) and C++ (std::string)
• Named parameters only: key=value pairs (no positional arguments)
• Multi-hop headers for routing: HEADER1:HEADER2:...
• Compact binary-friendly format: !!HEADER:MSG_KIND:COMMAND{key=val}##
• Small footprint: Arduino builds use fixed arrays, no dynamic allocation
• Full round-trip serialization support

Quick Example:

cmdlib::Command cmd;
cmd.msgKind = "REQUEST";
cmd.command = "MAKE_STAR";
cmd.setNamed("speed", "100");
cmd.setNamed("color", "red");
String output = cmd.toString();
// Output: !!REQUEST:MAKE_STAR{speed=100,color=red}##

Documentation: See CommandLibary/README.md

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2. PingPongHandler — Keep-Alive & Timeout Detection

An Arduino library that implements a bidirectional PING/PONG keep-alive protocol to detect connection idle states and timeouts. Built on top of CmdLib for reliable command handling.

Key Features:

• Automatic timeout detection with configurable idle window
• Global PING_IDLE flag accessible from anywhere
• Bidirectional: responds to PINGs and can send PINGs to other devices
• Serial port abstraction (works with Serial, Serial1, SoftwareSerial, etc.)
• Integrated with CmdLib for structured communication

Quick Example:

void setup() {
  Serial.begin(115200);
  PingPong.init(30000);  // 30-second idle timeout
}

void loop() {
  PingPong.update();  // Check for timeouts
  
  if (Serial.available()) {
    String cmd = Serial.readStringUntil('\n');
    PingPong.processRawCommand(cmd);
  }
  
  if (PingPong.isIdle()) {
    Serial.println("Connection lost");
  }
}

Documentation: See KeepAlive/README.md