@@ -307,12 +307,16 @@ Each user terminal provides a WebSocket based API for real-time control and noti
To remotely control the PTT button on the user terminal, [emit](https://socket.io/docs/client-api/#socket-emit-eventName-%E2%80%A6args-ack) a 'ptt' event on the socket.io connection. The event parameter must be a boolean value that represents the desired state of the button (true for pressed, false for released). The terminal will generate a response once the button has been switched to the desired state. The terminal will automatically release the PTT button if the socket.io connection is terminated.
When multiple clients control the PTT button simultaneously, the button will be held depressed as long as at least one client keeps the button depressed.
When multiple clients control the PTT button simultaneously, the button will be held depressed as long as at least one client keeps the button depressed. The button will be released when no client keeps the button depressed.
Note: If the microphone input on the speaker-mic is electrically disconnected while the physical PTT button is released (usually the case), remotely activating the PTT button will not activate the physical microphone.
## LED Indicator State
To get notified of changes in the state (color) of the LED indicator on the user terminal, the client emits a 'subscribe' event to the room 'indicator'. The value returned in the response represents the current color of the LED. On each LED color change, the terminal emits a 'change' event to the room with the new color. The subscription is terminated when the client either sends an 'unsubscribe' event to the room, or closes the WebSocket connection.
The LED color is represented with a string which contains either a well-known known name of the color (white, black), or a CSS formatted RGB string of the form '#RRGGBB'. All color names generated by the terminal can be parsed with the [color-parse](https://www.npmjs.com/package/color-parse) NPM package.
