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Cable connections:
Other pins are not used. Cable is wired straight through, meaning null modem cables will
not work. Do not attempt to connect this unit using non compatible cables or untested serial
ports. When used with a computer, beware of possible ground loops caused by the serial port
connection. Make sure you can access (and modify if necessary) the serial port settings on your
control device/computer. If you are not familiar with serial control, ask for assistance from a
qualified engineer.
Pin 2: TX data: data transmission output
Pin 3: RX data: data reception input
Pin 5: GND: ground
!!!IMPORTANT!!!
When the command (SET, GET, INC, DEC) is invalid, the unit will send: “ERROR: Unknown
Command!” When an invalid attribute is sent, the unit will reply: “ERROR: Unknown Attribute!”
When you attempt to send an instruction with a value out of range, the unit will reply: “ERROR:
Value Invalid!” However, this does not apply to output level related commands. In these cases,
the unit will set the value to the value closest to the absolute limit value. For example, you send
“SET MASTER -99”. The unit will not reply with an error message, instead, the reply will look
like this: “MASTER OFF”. The lowest possible Master level is -80, so -99 means that the master
is lower than the lowest (-80) value. The master will be muted. When a command that does
not require value feedback has been executed, the unit will reply: “Instruction Executed!”, for
example when the user definable display text or font type has been altered. When the instruction
is invalid, the reply will be: “ERROR: Invalid Instruction!”
When the text returned via RS232 is garbled or no communication is possible, adjust your
communications parameters to match those of the unit. Also make sure the front panel
operation is unlocked. When a communication error has occurred due to invalid communication
parameters or unknown characters, you will need to flush the RS232 buffer manually: when the
unit receives “<CR>” or “enter”, the buffer will be flushed. Alternatively, you might consider
cycling the power, just to be sure. During the power-on procedure, the unit will identify itself via
a text dump on the serial port. When no text is shown on your serial communication device while
the amplifier is performing its power-on self tests, your communication parameters or serial cable
are wrong, not connected or incompatible.
We suppose you are familiar with RS232 communication, serial cables and RS232 port settings.
In case you might experience RS232 communication problems, consult an experienced system
engineer to get you started.
