Stanford Research Systems SR785, Руководство по эксплуатации и программированию

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Data Transfer Commands 5-111
SR785 Dynamic Signal Analyzer
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.
SR785
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.
Host
On receipt of 1 (4-byte binary long int), executes a binary transfer to the SR785
of n 4-byte IEEE floats. The order is point 0, point 1, etc. Each 4-byte float is
transmitted least significant byte first. A total of 4n 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.
TGET ? i
The TGET command uploads a Trace buffer to the host computer. This
command is valid only via the GPIB interface. The parameter i selects a Trace
(1-5). Trace i must contain data.
The uploaded data should be saved in its entirety by the host computer. The
saved data can be downloaded back to the SR785 at a later time using TPUT.
The TGET and TPUT commands allow a host computer to save and reload a
trace buffer without using disks.
TGET uploads trace information as well as trace data. TPUT restores the trace
type, length and other attributes as well as the data.
The upload sequence is as follows:
Host
Send TGET ? i. Do NOT wait for IFC to be set in the Serial Poll status.
SR785
Returns n (4-byte binary long int) which is the number of bytes needed to
transfer the Trace buffer.
Host
On receipt of n (4-byte binary long int), executes a binary read from the SR785
of n bytes. Expect 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.