AR 10044005, Operating And Service Manual

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Model 5000A225A
20 Rev B
2.4.2 Remote Control Interface
This section describes remote operation of the Model 5000A225A using the provided General Purpose
Interface Bus (GPIB), RS-232, Fiber-Optic Serial, Universal Serial Bus (USB), and Ethernet 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 Keylock switch on the control panel of the Model 5000A225A allows it to be controlled using remote
communications. All remote queries will work in any Keylock switch position, but all remote commands will
only work when the position is set to REMOTE. When the Keylock switch is set to REMOTE all front panel
controls are disabled unless otherwise specified.
Due to the high power output capability of the Model 5000A225A there is a built-in safety mechanism while
the Keylock switch is in the REMOTE position. Once the RF is instructed to go to an on state, it is necessary
to continually communicate over any of the remote I/O ports on a periodic basis. The timing for this periodic
basis is determined by the Remote Operate Timeout (ROPTO) command found in Section 2.4.2.6.18.
2.4.2.1 GPIB (IEEE-488) Communication
For GPIB operation, the device address is set using the front panel touch screen. Ensure that each device
connected to the GPIB is set to a unique address.
To send commands be sure that the Model 5000A225A’s address is set properly and that the controller has
correctly identified it as a “listening” device.
When sending commands via the GPIB interface, terminate with an EOI and a Line Feed character. The
5000A225A will ignore characters following the termination.
2.4.2.1.1 Setting the GPIB (IEEE-488) 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 2.4.1.5.8). 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.
2.4.2.2 RS-232 Communication
The RS-232 port is a serial communications bus. All commands and queries through this port must be
terminated with a Line Feed character. 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 message followed by a Line Feed character is sent out from this port.
The baud rate for the RS-232 port is user selectable from the RS-232/Fiber-Optic Serial Baud Rate selection
screen. To get there from the Main Menu, touch the User menu button followed by the I/O menu button and
finally the Serial menu button. A thin black outline indicates the present baud rate selection. When the back