Advanced Command & Feedback Reference

1. The real execution model

UI action
  → sendCommandFromDevice()
  → extender.executeCommand()
  → localhost gateway
  → socket / websocket / secure transport
  → device
  → raw response
  → AnalyseFeedback()
  → display_line update

2. Action commands vs query commands

Action command

PLAY → player/set_play_state?pid={pid}&state=play

• Changes device state.
• May return only success or nothing useful.
• Does not automatically update title, artist, volume or power state.

Query command

TITLE QUERY → player/get_now_playing_media?pid={pid}

• Requests current device state.
• Returns raw data.
• Feeds AnalyseFeedback().

3. Which queries are called by the UI?

MyURemote does not continuously run every possible query. The active zone, input and enabled feedback flags determine which queries are called.

Main scheduler

fnQueryState()
  → fnQueryStateAmplifier()       immediately
  → fnQueryRow1()                 after 2 seconds
  → fnQueryStateAmplifier()       after 3 seconds
  → fnQueryRow2()                 after 5 seconds
  → fnQueryStateAmplifier()       after 6 seconds
  → fnQueryRow3()                 after 8 seconds
  → fnQueryStateAmplifier()       after 9 seconds
  → fnQueryRow4()                 after 11 seconds

Amplifier queries

Current input device queries

4. Feedback fields used by MyURemote

Each feedback type has its own command and parsing settings. The parser does not know what a title, artist or volume is. It only receives a raw response and extraction rules.

5. The feedback parser model

The generic parser is AnalyseFeedback(response, Prefix, Hex, Position, Digits, StopSign, WhatFeedback).

Meaning of each setting

Text extraction logic

value starts at:
  indexOf(Prefix) + Prefix.length + Position

value ends at:
  StopSign

if StopSign is empty or not usable:
  Digits is used

6. StopSign rules

StopSign is the marker that tells MyURemote where the extracted value ends. It is often more important than Digits.

Common StopSigns

Important ASCII / HEX references

7. Hex, text and escaped values

Text / JSON response

{"heos":{"message":"pid=123&level=13"}}

Use Hex = false. Extract with Prefix, Position and StopSign.

Pure hex string response

1b920318080210021a

Use hex parsing only when the response is actually a hex string or binary protocol data.

Binary / raw byte response

\x02\x01\xFF

Some protocols return non-printable bytes. In that case MyURemote may convert the raw string to bytes before parsing.

8. HEOS example: title, artist, station, volume

HEOS is a good example because the command succeeds, but the display only works when the response is parsed correctly.

HEOS transport commands

HEOS volume response

{"heos":{"command":"player/get_volume","result":"success","message":"pid=123&level=13"}}

HEOS now playing response

{"heos":{"command":"player/get_now_playing_media","result":"success"},"payload":{"type":"station","song":"Re-Rewind","station":"Nostalgie 90's & 00's","album":"","artist":"Artful Dodger"}}

Recommended HEOS text settings when the response remains escaped

This is recommended when raw quotes cannot safely be stored in devices.js.

Alternative HEOS settings when quotes are unescaped

If heos.js converts \" to ", then the response becomes normal JSON text. In that case use:

HEOS play state as power status

player/get_play_state?pid={pid}

HEOS does not provide a classic amplifier power state. For UI purposes, play state can be used as a logical power/activity state.

9. What OK really means

OK only means:

• The gateway accepted the request.
• The connection/write probably succeeded.

It does not mean:

• The device executed the command.
• The device state changed.
• The UI has enough data to update.

10. Troubleshooting checklist

Recommended debug logging inside AnalyseFeedback

console.log("varPrefix:", varPrefix);
console.log("varPosition:", varPosition);
console.log("varDigits before:", varDigits);
console.log("varStopSign:", varStopSign);
console.log("mResultBrut:", mResultBrut);

varPositionPrefix = (mResultBrut.indexOf(varPrefix) + 1 + varPrefix.length);
console.log("indexOf prefix:", mResultBrut.indexOf(varPrefix));
console.log("varPositionPrefix:", varPositionPrefix);
console.log("text from prefix:", mResultBrut.substring(varPositionPrefix - 1, varPositionPrefix + 80));

if (varStopSign != "") {
  var stopIndex = mResultBrut.indexOf(varStopSign, varPositionPrefix);
  console.log("stopIndex:", stopIndex);
  console.log("text at stop:", mResultBrut.substring(stopIndex - 10, stopIndex + 10));
}

Final model

transport + query + parsing = UI state

MyURemote integrations become reliable when commands, responses and feedback settings are treated as one deterministic chain.