Stanford Research Systems SR785, Руководство по эксплуатации и программированию

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Data Transfer Commands 5-109
SR785 Dynamic Signal Analyzer
The returned value is either a frequency (spectra), a time (time record or
correlation) or a band center frequency (octave).
FBIN ? d, x
The FBIN ? command queries the bin number of x (frequency or time) in display
d. The parameter d selects Display A (0) or Display B (1). The parameter x is a
floating point value of Hz or seconds.
The returned value is an integer bin number.
TLOD ? i, n
The TLOD command loads binary data into Trace i. The parameter i selects
Trace 1 through 5. This command is valid only via the GPIB interface.
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.
TLOD 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.
The download sequence is as follows:
Host
Send TLOD ? 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 binary transfer to the SR785
of 2n 4-byte IEEE 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 4-byte float is transmitted
least significant byte first. A total of 8n bytes are transferred. 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.
TASC ? i, n
The TASC command loads ASCII data into Trace i. The parameter i selects
Trace 1 through 5. This command is valid only via the GPIB interface.