Stanford Research Systems DS345, Manual

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Arbitrary Waveform Composer
7-5
Use the math functions by selecting the desired function with the mouse, and
clicking Okay. Several parameters must be entered: the starting point number
on which the operation should take place, the number of points over which the
function should operate, and the amplitude of the function. Exponentials also
require that the damping factor b be entered. If the amplitude of the resultant
waveform exceeds the range of the DS345 an error message will be displayed.
Send Data Menu The selections in the send data menu allow transmitting the arbitrary waveform
to the DS345. The Send Data menu is enabled only when the communications
parameters have been set in the
Set DS345 .
Waveform This selection sends the current arbitrary waveform to the DS345. When the
waveform is sent to the DS345 the state of the DS345 is set to match that of
AWC. That is, the DS345's sampling rate and trigger parameters are set to
match the settings in AWC. This selection is disabled if no waveform has been
generated. While sending the data, the message "Sending data points to
DS345. Please wait..." is displayed. At the same time the DS345 should
display the message "loading..". Using the GPIB interface, a 16000 point
waveform takes about 7 seconds to transmit. Using RS232, transfer times are
longer and depend on the Baud rate. After loading is complete the arbitrary
wave can be observed at the output of the DS345 by selecting the ARB
function from the front panel or through the
trigger menu in AWC (see below).
ASCII file This selection sends an ASCII file directly from disk to the DS345. There is no
processing of the file contents- the user must ensure that the contents will be
recognized by the DS345. A file selection box is displayed to select the proper
file. The ASCII file can be used to send a series of commands to the DS345. It
can also be used as a macro facility to perform a series of commands on the
unit.
Warning : The ASCII File command does not perform any error checking
(syntax or otherwise) on the commands that the user is sending to the DS345.
Double checking the ASCII file is a good idea since an error could yield
unpredictable results.
Set DS345 Menu The Set DS345 menu is used to remotely set the sampling frequency of the
DS345 and to set communication parameters.
Sampling Frequency This selection sets the DS345's arbitrary waveform sampling frequency. The
selection is disabled when no waveform is displayed on the screen. The
frequency range is from .001Hz to 40,000,000.0Hz. Note that the sampling
frequency can only be 40MHz/N where N is an integer. If a frequency is
entered where N is not an integer, the DS345 will round it to the closest
40MHz/N value.
RS232/GPIB This selection is used to set communication parameters for the interface
between AWC and the DS345. When you select this menu item, the program
checks for available VISA resources on your system. Depending on your
system, this may take several seconds.