v1.15.3 - Add GET_USAGE command (2025-12-12)

What Changed?

This release adds the GET_USAGE command which provides a simple, machine-readable list of all available commands with their descriptions. This makes it easy for clients to discover and document the complete command interface without needing to parse complex help text.

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What's New

Main Feature: GET_USAGE Command

What it does: Returns a JSON array containing all available commands with their descriptions. Each entry includes the command name and a brief description of what it does. This provides a complete, machine-readable inventory of the device's command interface.

How to use it: Send the GET_USAGE command to the device via serial:

GET_USAGE

The device responds with a JSON object containing a commands array.

Response example:

{
  "type": "response",
  "status": "ok",
  "sent_at": 1234567890,
  "commands": [
    {
      "command": "GET_VERSION",
      "description": "Firmware version"
    },
    {
      "command": "GET_BUILD_TYPE",
      "description": "Build type/environment"
    },
    {
      "command": "GET_STATUS",
      "description": "Display system status"
    },
    {
      "command": "GET_MAC_ADDRESS",
      "description": "MAC address"
    },
    {
      "command": "GET_BME280",
      "description": "All BME280 sensor data"
    },
    {
      "command": "GET_BME280_TMP",
      "description": "BME280 temperature"
    },
    {
      "command": "GET_BME280_ATM",
      "description": "BME280 pressure"
    },
    {
      "command": "GET_BME280_HMD",
      "description": "BME280 humidity"
    },
    {
      "command": "SET_POLL_COUNT",
      "description": "Set poll count"
    },
    {
      "command": "GET_POLL_COUNT",
      "description": "Get poll count"
    },
    {
      "command": "SET_THRESHOLD",
      "description": "Set DAC threshold"
    },
    {
      "command": "GET_THRESHOLD",
      "description": "Get DAC threshold"
    },
    {
      "command": "SET_DEADTIME",
      "description": "Set detector deadtime"
    },
    {
      "command": "GET_DEADTIME",
      "description": "Get detector deadtime"
    },
    {
      "command": "TEST_LED",
      "description": "Test LED control"
    },
    {
      "command": "GET_UPTIME",
      "description": "System uptime"
    },
    {
      "command": "GET_TIME",
      "description": "Get RTC/GNSS time and difference"
    },
    {
      "command": "GET_HELP",
      "description": "Command reference"
    },
    {
      "command": "GET_USAGE",
      "description": "List all available commands"
    },
    {
      "command": "SET_STREAM",
      "description": "Enable/disable detection output"
    },
    {
      "command": "GET_STREAM",
      "description": "Query stream status"
    },
    {
      "command": "RESET",
      "description": "Factory reset"
    },
    {
      "command": "SET_RTC_TIME",
      "description": "Set device time"
    },
    {
      "command": "GET_RTC_TIME",
      "description": "Get device time"
    },
    {
      "command": "GET_GNSS",
      "description": "Get all GNSS data including state"
    },
    {
      "command": "GET_GNSS_LATITUDE",
      "description": "Get GNSS latitude"
    },
    {
      "command": "GET_GNSS_LONGITUDE",
      "description": "Get GNSS longitude"
    },
    {
      "command": "GET_GNSS_ALTITUDE",
      "description": "Get GNSS altitude"
    },
    {
      "command": "GET_GNSS_POSITION",
      "description": "Get GNSS position data"
    },
    {
      "command": "GET_GNSS_TIME",
      "description": "Get GNSS unix timestamp"
    },
    {
      "command": "GET_GNSS_TIME_MS",
      "description": "Get GNSS timestamp in milliseconds"
    },
    {
      "command": "GET_GNSS_TIME_US",
      "description": "Get GNSS timestamp in microseconds"
    },
    {
      "command": "GET_GNSS_CS",
      "description": "Get GNSS centisecond"
    },
    {
      "command": "GET_GNSS_SATELLITES",
      "description": "Get satellite count"
    },
    {
      "command": "GET_GNSS_QUALITY",
      "description": "Get fix quality"
    },
    {
      "command": "GET_GNSS_VALID",
      "description": "Get fix validity"
    },
    {
      "command": "GET_GNSS_HDOP",
      "description": "Get HDOP"
    },
    {
      "command": "GET_GNSS_STATE",
      "description": "Get GNSS module state"
    },
    {
      "command": "SET_WIFI_SSID",
      "description": "Connect to WiFi"
    },
    {
      "command": "SET_WIFI_ENABLE",
      "description": "Enable/disable WiFi"
    },
    {
      "command": "GET_WIFI",
      "description": "WiFi status"
    }
  ]
}

---

Installation

Quick Start

# Get the release
git checkout v1.15.3

# Build
task build

# Upload
task upload

# Check it works
task monitor

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What's Different from the Last Version?

✅ Added

• GET_USAGE command - Returns machine-readable list of all available commands with descriptions

🔧 Changed

• Command dispatcher now includes GET_USAGE entry in the dispatch table

🐛 Fixed

• None in this release

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Is It Safe to Upgrade?

Backward Compatible: Yes

• No changes to existing commands or behavior
• GET_USAGE is a new read-only command with no side effects
• All existing client code continues to work unchanged

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Tests Passed

• ✅ Builds without errors
• ✅ New command handler compiles correctly
• ✅ Dispatch table properly configured
• ✅ Command metadata correctly populated from dispatch table

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Release Details

• Date: 2025-12-12
• Version: v1.15.3
• Files Changed: 2 (src/command/usage.cpp, src/command_manager.cpp)

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Next Steps

Future enhancements could include:

• Auto-generating documentation from GET_USAGE response
• Adding command filtering (e.g., GET_USAGE --category system)