Stanford Research Systems SR780, Operating Manual And Programming Reference

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5-94 Data Transfer Commands
SR780 Network Signal Analyzer
A trace contains n complex points. The value of n depends upon the type and
length of the target trace. See TLOD for more.
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.
SR780
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 SR780 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.
Each point is a 4-byte IEEE float number and range from -1.0 to +1.0. A value of
1.0 is output at 100% amplitude as 1 Volt. The data should not exceed this range.
The download sequence is as follows:
Host
Send ALOD ? n. Do NOT wait for IFC to be set in the Serial Poll status.
SR780
Checks to make sure that the Arbitrary buffer has sufficient length. Returns 1 (4-
byte binary long int) if OK to begin data transfer. A return of 0 indicates that n is
too large for the buffer.