Tegam 2411B, Operation Manual

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Chapter 8 Advanced Remote Operation
Remote Command Set - Introduction
Remote Command Set
Introduction
Both RS-232 and GPIB share the same command set except as noted. Many of the command set has an
equivalent front panel counterpart. Therefore, it is recommended that you are thoroughly familiar with
the front panel operation of the Model 2411B before beginning any programming.
***IMPORTANT NOTE***
In order to eliminate some of the common errors encountered while programming instruments, the
Model 2411B has adopted a unique approach to sending and executing <PROGRAM MESSAGES>.
The following discussions on
command sequence and command execution explain this approach.
Command Sequence
Normally a series of commands (or <PROGRAM MESSAGE UNITS>) are sent as a single
<PROGRAM MESSAGE> according to the rules outlined in Section 10.4. While these commands are
generally executed sequentially, there are certain conditions where the absolute sequential execution of
the commands would cause a device error. Take for example the following situation:
Output amplitude is 5Vpp, with offset of 0V
The new test setup calls for an output setting of 1Vpp with +7.5V offset.
(Note: Maximum output amplitude is l0Vpeak)
With most instruments that execute commands sequentially it would be required to first change the
amplitude, then change the offset, in order to prevent a device error (caused by the sum of amplitude and
offset exceeding 10.4Vpeak; see “ERROR CODES” in the Appendix). Because the Model 2411B is not
sequence dependent (except for “WVFM” commands), the command order (within a single <PRO-
GRAM MESSAGE>) is of no consequence . Thus both of the following messages would execute prop-
erly without a device error.
AMPL 1.0;OFFSET 7.5
or
OFFSET 7.5;AMPL 1.0
Command Execution
As already alluded to in the preceding paragraph, in order for the Model 2411B to recognize and execute
a command, or series of commands, they usually must be followed by the EXECUTE command. This
command is equivalent to the front panel <ENTER> button, and allows the programmer to send a com-
plete
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