APART SDQ5Pir, Instruction Manual

Page: 10 / 20

8
Active loudspeaker set
RS232 communication
Communication with SDQ5PIR via RS232 is done with simple ASCII
commands and replies. The port settings are 19200 Baudrate, 8 data
bits, 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<CR> ”. 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<CR> ”. 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).