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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 influence 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 first 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 first.
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 specified. 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
