AR 10046249, Operating And Service Manual, Page: 28 / 58

Model 150/150AW1000
8 Rev C
2.4 REMOTE COMMUNICATIONS
This section describes remote operation of this product using the installed communications ports connected to
a remote device such as a personal computer. All ports are active at all times, however only one port may be
used at a time. Communicating through two or more ports at one time will cause data collisions and lost
commands or queries.
The REMOTE / LOCAL switch on the front panel allows for the amplifier to be controlled using the remote
communications ports or the front panel controls depending on its position. All remote queries will work in
either switch position. All remote commands will only work when the switch is set to REMOTE . When the
switch is set to REMOTE all front panel controls are disabled.
NOTE: Some of the following ports may not be installed on your amplifier.
2.4.1 IEEE-488 (GPIB) Communications
For IEEE-488 operation, the device address is set using the dip switches on the rear panel of the amplifier. It
is set to address 1 at the factory. If another device on the IEEE-488 bus is already using address 1, reset the
switch to a vacant address. (Resetting the address requires re-booting the unit).
Specific IEEE-488 bus commands depend on which software package you are using. To send commands be
sure that the amplifier’s address is set properly and that the controller has correctly identified the unit as a
“listening” device.
When sending commands to the unit via the GPIB interface, terminate the command with a <LF> , an EOI , or
both. The system ignores characters following the termination.
2.4.1.1 Setting the IEEE-488 (GPIB) Address
The GPIB device address can be set to any number between 1 and 30. This selection is made by navigating to
the GPIB address selection screen (Section 3.3.1.5.4). To get there from the Main Menu, touch the User menu
button followed by the I/O menu button and finally the GPIB menu button. Touching any of the buttons labeled
1 to 30 immediately sets the GPIB address to the corresponding value. A thin black outline indicates the present
GPIB address selection. When the back button is pushed the address selection is stored to non-volatile memory.
Therefore, if power is lost prior to hitting the back button any address selection changes will be lost. The default
GPIB address is 1.
2.4.2 RS-232 Communications
The RS-232 port is a serial communications bus. All commands and queries through this port must be
terminated with a <LF>. When a valid query is received, it is processed and the result is immediately
transmitted back over the RS-232 interface. This port is designed to time-out if there is no activity on the bus
for more than 5 seconds. At this time the internal buffer is cleared and a TIMEOUT_ERROR<LF> message
is sent out from this port.
The RS-232 port is setup as a DCE port. When connecting to a PC a straight one-to-one cable should be used.
A null modem is NOT needed. The settings and pinout diagram for this port can been found below.