Protocol Specs
Table Of Contents
Note: Special characters '&', '=', and '%' in the JSON response fields are encoded to '%26(&)', '%3D(=)', and '%25(%)'. 
4. Command and Response Details
4.1 System Commands
4.1.1 Register for Change Events
By default HEOS speaker does not send Change events. Controller needs to send this command with enable=on when it is ready to 
receive unsolicit responses from CLI. Please refer to "Driver Initialization" section regarding when to register for change events.
Command: heos://system/register_for_change_events?enable='on_or_off' 
Attribute Description Enumeration
enable Register or unregister for change events. on,off
Response:
{
 "heos": {
 "command": "system/register_for_change_events",
 "result": "success",
 "message": "enable='on_or_off'"
 }
}
Example: heos://system/register_for_change_events?enable=on 
4.1.2 HEOS Account Check
Command: heos://system/check_account
This command returns current user name in its message field if the user is currently singed in. 
Response:
{
 "heos": {
 "command": "system/check_account",
 "result": "success",
 "message": "signed_out" or "signed_in&un=<current user name>" 
 }
} 
Example: heos://system/check_account
4.1.3 HEOS Account Sign In
Command: heos://system/sign_in?un=heos_username&pw=heos_password
Attribute Description Enumeration
un HEOS account username N/A
pw HEOS account password N/A
Response:
{
 "heos": {
 "command": "system/sign_in ",
 "result": "success",
 "message": "signed_in&un=<current user name>"
 }
}










