Operation Manual
9
System command format
Pin No.
Connection
1
No connection
2
RS-232 receive (RX)
3
No connection
4
No connection
5
Ground
6 No connection
7
No connection
8
No connection
9 No connection
Command
Type
RS-232
Command
MULTIzone command response
SYSTEM $s99sbyoff All units enter standby mode
SYSTEM $s99sbyon All units power up out of standby
SYSTEM $s99muten All units all zones enter mute
SYSTEM $s99mutdis All units all zones de-mute
SYSTEM $s99comen All units all zones enter RS-232 control mode
SYSTEM $s99comdis All units all zones enter manual front panel control mode
Appendix 4
RS-232 Interface
An RS-232 control interface allows remote control of all basic functions of MULTIzone. The RS-232 interface is uni-directional, MULTI-
zone does not transmit any data. Commands will be sent as RS-232 serial communication at 9600 baud, 8 bits, no parity bits, 1 stop
bit and no ow control. All characters will be sent as ASCII, not delimited and ending with a line feed (0x0A).
Multiple MULTIzone units can either be addressed and controlled from separate RS-232 control sources, or alternatively the user is
able to set an address for each MULTIzone unit via its rear panel switches, allowing multiple chained units to be controlled from a
single RS-232 control source. If this feature is required, then the user simply sets the RS-232 source to “LOOP” via the rear panel
switch (DIP switch #4) and assigns a dierent address for each MULTIzone unit (DIP switches 1, 2 and 3). RS-232 data is then relayed
to each looped unit using the same cable as the signal loop-through.
A DIP switch setting “000” locks the unit into manual panel mode, disabling all RS-232 control for that unit – see page 6.
Note: when using RS-232 control, no more than 7 units can be looped using a single RS-232 controller (i.e. up to 28 zones).
A structure of RS-232 commands is provided that allow operation of MULTIzone at the ‘system‘ level, ‘unit’ level or ‘zone’ level.
System commands cause every MULTIzone to respond. Unit commands cause only the addressed unit to respond. Zone commands
cause only the selected zone on a selected unit to respond.
The RS-232 interface has additional functionality in that it can be used to put MULTIzone in standby. A specic “sbyo” command
will reduce power consumption to <0.5W by shutting down all internal systems. An “sbyon” command will then restore system
operation but it is important to note that the unit will take several seconds to fully awake, during which time no audio will be heard
and no other RS-232 commands can be received or acted upon. The programming of the RS-232 source device must take this into
consideration.
RS-232 connector wiring