5
INTRODUCTION
The purpose of this document is to describe how the serial control
interface of the device works.
SERIAL SETTINGS
The port settings should always be 8 data bits, no parity and one stop
bit. The baud rate can be changed from the user interface. Supported
speeds are 9600 (default), 19200, 38400, 57600 and 115200 bits per
second. Hardware handshake is optional and it can be enabled from the
UI. All commands and responses are in ASCII form.
SERIAL PROTOCOL
Commands
Every command starts with ‘!’ character and ends with carriage return
(ascii 0x0d, referred in this document as <CR>). There are two types of
commands, direct commands and status requests. Direct commands are
used to emulate remote key presses or to set a certain volume etc. Status
requests are used to query the current state of the controller (volume,
current source etc.).
Commands with invalid format are simply ignored. For example, sending
a command !VOL(100)garbageMUTEON<CR> will only result in volume
being muted, because volume command is not terminated properly.
Responses and feedback level
There are three levels of responsiveness and they are called feedback
levels. Each level adds something new on top of the previous level.
Feedback level can be set from the UI or from serial interface with
command “!VERB(X)<CR>” (X can be 0, 1 or 2). All responses start either
with ‘!’ (status messages) or ‘#’ (echo messages) and end with <CR>.
Feedback level 0: Data is only sent when data is requested by status
request command. For example command “!VOL?<CR>” would return
“!VOL(XX)<CR>”, where “XX” would be current volume.
Feedback level 1: Data is sent whenever any of the statuses listed in table
2.1 changes. The data format is same as with responses to status request
command. For example volume status will be sent as long as volume is
Summary of Contents for P1
Page 4: ...4 ...
