Stanford Research Systems SR620, Руководство пользователя

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Programming Commands 33
SR620 Universal Time Interval Counter
returned is from the measurement desired. Also,
no other queries should be sent between sending
the MEAS? query and reading its answer.
XALL?
The XALL? query returns the values of the mean,
rel, jitterl, max, and min of the last completed
measurement. These numbers are returned as
one string with the individual numbers separated
by commas. The numbers are floating point
values with up to 16 digits of precision.
XAVG?
The XAVG? query returns the value of the mean
of the last completed measurement. The number
returned is a floating point value with up to 16
digits of precision. If the REL is set the number
returned is the REL'D value.
XJIT?
The XJIT? query returns the value of the jitter of
the last completed measurement. The number
returned is a floating point value with up to 16
digits of precision.
XMAX?
The XMAX? query returns the value of the
maximum of the last completed measurement.
The number returned is a floating point value with
up to 16 digits of precision. If the rel is set the
number returned is the REL'd value.
XMIN?
The XMIN? query returns the value of the
minimum of the last completed measurement.
The number returned is a floating point value with
up to 16 digits of precision. If the rel is set the
number returned is the REL'D value.
XREL(?) x
The XREL command sets the display REL to the
value x. The XREL? query returns the value of the
REL.
XHST? j
The XHST? query returns section j (j=0 to 9) of the
histogram display as 4 byte binary integers least
significant byte first. Each section consists of the
data for 25 histogram points (100 bytes total plus
terminator). There is no separator between
successive points. If the rs232 interface is being
used an 8 bit data word must be chosen to
correctly transmit this data. The data returned is
binned into 250 bins- not the number set by the
front panel. This command allows one to rapidly
read the entire contents of the histogram display. If
the histogram is blank the illegal numbars -0 are
returned.
HSPT? j
The HSPT? query returns the value of point j of
the current histogram. J has the range 1 to 250. If
the histogram is blank this query returns the illegal
value 9E20.
SCAV? j
The SCAV? query returns the value of point j of
the mean graph or scan point j. J has the range of
1 to 250. This query returns the illegal value 9E20
if the stripchart is blank, has not reached point j, or
the scan has not reached point j. One way to read
back every point of a scan is to continually send
the command SCAV? j until a legal value results
and then move on to the next point. The number
returned is a floating point number with up to 16
digits of precision.
SCJT? j
The SCJT? query returns the value of point j of the
jitter graph or scan point j. J has the range of 1 to
250. This query returns the illegal value 9E20 if
the stripchart is blank, or the scan has not reached
point j. One way to read back every point of a
scan is to continually send the command SCAV? j
until a legal value results and then move on to the
next point. The number returned is a floating point
number with up to 15 digits of precision.
BDMP j
The BDMP command puts the SR620 into its high-
speed binary dump mode. j specifies the number
of points to be dumped and may range from 1 to
65535. THIS COMMAND FUNCTIONS ONLY ON
GPIB. At the maximum baud rate RS232 would
offer no speed improvement so this command is
not functional on RS232. On receipt of the BDMP
command the SR620 does the following: (1) the
display shows the message "BINARY
OUTPUT",(2) the SR620 automatically enters
automeasure mode with a sample size of one,
and, (3) disables the keyboard except for the
"RESET" key.