APart SDQ5PIR-W [4/12] Rs232 communication

WWW.APART-AUDIO.COM

Communication with SDQ5Pir via RS232 is done with simple ASCII Commands and Replies. The port

settings are 19200 Baudrate, 8 databits, no parity and 1 stop bit. The physical connection is as described

below:

Standard 9 pin serial cable, wired straight through (no null modem cable !!!). Maximum wire length

depends on cable quality and inuence from external interference.

Pin 2: TX data: data transmission output

Pin 3: RX data: data reception input

Pin 5: GND: ground

Other pins are not used.

NOTE: when the unit is in standby mode, it may not respond to the rst command sent to the unit, unless

you send the command “SET STANDBY OFF”. If you want to send any other command while the unit is in

standby mode, it will wake up from standby and reply “STANDBY OFF”. After that, resend the command

and it will be executed.

An instruction has at least a command and an attribute. In many cases, there are extra values needed,

like a source name/character or a value. From here we assume that you are familiar with RS232

communication protocols and connections. If not, please read the user manual of your control device rst.

Instructions always have to be ended with <CR>, carriage return. Line feed <LF> characters will always be

omitted, however SDQ5Pir can use (and echo) <LF> after a <CR>. Instructions are not case sensitive!

The 4 possible commands are: SET, GET, INC and DEC. With the INC and DEC command, a “step value”

can be specied. See the table below for details (in the value column).

Operating Settings:

SDQLVL is the volume level of the speaker system. Possible values are: OFF (mute) or any value between

-63 (lowest) and 0 (highest volume level). E.g. you want to set the volume to -20: SET SDQLVL -20 <CR>

The unit will reply: SDQLVL -20

MAXLVL is the maximum allowed volume level. E.g. if you don’t want anyone to set the SDQ level higher

than -10, set the MAXLVL parameter to -10. All volume related commands will ALWAYS be related to the

MAXLVL setting. E.g. if the MAXLVL is -10 and you enter the command SET SDQLVL -20, the SDQ5Pir

will set the level relative to the MAXLVL, which was -10.

Please note that the absolute maximum number of volume steps is limited to 64 steps. 1 volume step

corresponds to 1.25 dB.

The MAXLVL parameter is therefore considered as the master volume. If you want to mute the speaker,

you can set the MAXLVL parameter to OFF.

BALANCE sets the balance between left and right channel. Possible values vary between -31 and 31.

Equalizer:

EQBASS sets the level of the bass.

EQTREB sets the level of the treble.

The value must be between -14 and 14 in steps of 2. If a different value is used (e.g. “5”), it will be

changed to the closest match.

RS232 communication