Stanford Research Systems SR785, Operating Manual And Programming Reference

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5-110 Data Transfer Commands
SR785 Dynamic Signal Analyzer
The target Trace i must already store data of the measurement type and length to
be loaded from the interface. The loaded data simply takes the place of the stored
trace data and assumes the measurement parameters (Measurement, Averaging,
Window, Frequency span, etc.) and length of Trace i.
TASC loads the actual complex data values in the trace, NOT the data displayed
in a particular view. Remember, views are simply different ways of showing the
actual complex data.
A trace contains n complex points. The value of n depends upon the type and
length of the target trace. N should be chosen equal to or less than the length of
the target trace. If the length is less than that of the target trace the remainder of
the trace will be filled with zeros.
Each complex point is two floating point numbers, representing the real and
imaginary parts. Thus, the TASC command loads 2n floating point numbers (in
ASCII format).
The downloaded values are assumed to have the same units as the target trace.
Depending upon the trace measurement, the values are assumed to be either
unitless, Volts or Volts
2
. See TLOD for more.
The download sequence is as follows:
Host
Send TASC ? i, n. Do NOT wait for IFC to be set in the Serial Poll status.
SR785
Checks to make sure that Trace i has length n. Returns 1 (4-byte binary long int)
if OK to begin data transfer. A return of 0 indicates that n is too large for Trace i.
Host
On receipt of 1 (4-byte binary long int), executes a transfer to the SR785 of 2n
ASCII floats. The order is real part of point 0, imag part of point 0, real part of
point 1, imag part of point 1, etc. Each ASCII float is delimited by a comma,
space, tab or carriage return (NOT EOI). Assert EOI with the final byte of the
transfer.
Serial Poll until IFC (bit 7) is set in the Serial Poll status before sending another
command.
ALOD ? n
The ALOD command loads binary data into the Arbitrary Waveform buffer.
This command is valid only via the GPIB interface.
The parameter n specifies the number of points to be loaded and must be a
multiple of 2048. The Arbitrary Waveform buffer must already have sufficient
memory allocated. After the load is complete, the Arbitrary Length will be n
points.