Stanford Research Systems SR785, Operating Manual And Programming Reference

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5-26 Remote Programming
SR785 Dynamic Signal Analyzer
Likewise, to set the span to 51.2 kHz one could send any one of these five equivalent
commands:
FSPN 2, 51200
FSPN 2, 51.2 kHz
FSPN 2, 51200 Hz
FSPN 2, 51200000 mHz
FSPN 2,5.12E10 uHz
Actually, it is only necesssary to send sufficient characters to uniquely identify the units
from the list. Thus FSPN 2, 51.2 k would set the span to 51.2 kHz as well.
Regardless of the units used to set the parameter, the analyzer almost always returns the
result of queries in one unit. So if the span were queried after any of the above
commands were sent, the analyzer would return 51200.
It is never necessary to send a unit string with a set command. Each command has a
"default unit" which it will use if no units are sent with the value. The default units are
also the units used when the analyzer responds to queries.
Some commands must identify the units in which queries are responded to. Examples
would be the source amplitude and input range commands which can return values in dB
and linear units In these cases, the response to the query is in the form: f,j where f is the
actual floating point return value, and j is the index into the list of units which uniquely
identifies the units of f. These commands are identified in the individual command
description.
In the detailed command descriptions, lists of allowed units are indicated in angle
brackets <>. Within the list, the default units are listed surrounded by square brackets [].
For instance, for the above command, the allowed unit list would be written as:
<kHz, [Hz], mHz,
µ
Hz>
Help
The detailed command list is available on screen by pressing [Help/Local] to enter the
help system. Press [4] to show the command list. Commands are also cross referenced in
the help about each key.