Stanford Research Systems SR620, Руководство пользователя

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38 Programming Commands
SR620 Universal Time Interval Counter
*WAI
The *WAI (wait) common command is a
synchronization command that holds off all further
command execution until all in progress
measurements/scans/prints are complete. This
command ensures that a particular operation is
finished before continuing. An example of the
usefulness of this command is ensuring that a
measurement is complete before reading the
answer. The command line STRT;*WAI;XAVG?
will start a measurement, wait until it is done, and
send back the mean value.
ENDT {j,k,l,m}
The ENDT command sets the RS232 end of
transmission terminator. This terminator is
appended the the end of each answer and may
consist of up to 4 ASCII (decimal) characters. The
default terminator is <cr><lf> and is obtained by
omitting the parameters. The parameters j,k,l,m
are the decimal representations of between 1 and
4 termination characters. For example, if it
desired that the termination be the characters
carriage return and "E" the command would be
ENDT 13,69.
STUP?
The STUP? query returns the complete setup of the SR620 as a long string of numbers separated by
commas. All setup information except for trigger levels and d/a starting and step voltages is returned.
The meanings of the returned numbers are as follows: (when bits are packed into a status byte the bit
values correspond to those used by the normal mode setting command. For example, the AUTM
command with parameter j=1 turns on automeasure mode and automeasure bit (setup byte 1, bit 0) is 1 if
automeasure is on)
position meaning parameter
format
1 instrument mode same as MODE command
2 source same as SRCE command
3 arming mode same as ARMM command
4 gate multiplier same as front panel control (0= 1E-4, 1= 2E-4, etc.)
5 sample size 0,1,..,18 corresponding to 1,2,5,...,10^6
6 display source same as DISP command
7 graph source same as DGPH command
8 setup byte 1 bits of byte are:0-auto measure on/off, 1 autoprint on/off,2 -rel
on/off, 3- x1000 on/off 4 - arming parity (+-time),5- jitter type
Allan/Std Dev ,6- clock ext/int,7- clock freq10MHz /5 MHz
9 setup byte 2 bits are: 0,1 - A,B autolevel on;2,3- DVM0
gain(auto=0,20V=1,2V=2);4,5 A,B prescaler enabled; 6,7-DVM1
gain
10 setup byte 3 bits are: 0- Ext terminator,1- Ext slope,2- A slope, 3- A ac/dc,4- B
slope,5- B ac/dc
11 setup byte 4bits are:0,1- A terminator; 2,3- B terminator;4,5- print port mode
12 histogram vert scale 0,1,... corresponding to 1,2,5...
13 histogram horiz scale 0,1,... corresponding to 1,2,5 * led display least significant digit
(ps, uHz, etc.)
14 histogram bin number 0,0,... corresponding to 1,2,5,10,...
15 mean graph vert scale same as histogram horiz scale
16 jitter graph vert scale same as histogram horiz scale
17 setup byte 5 bits are: 0-4 plotter address,5- plot/print 6 - plot gpib/rs232
18 setup byte 6 bits are:0-1 d/a output mode (chart/d/a),2 graph on/off,3-6 # scan
points, 7 ref output level
19 rs232 wait same as WAIT command
20 scan setup byte 0-3 - stepsize corresponding to 1E-6, 2E-6, etc.; 4,5 - delay scan
enable
21,22 scan starting delay bytes 1,0 delay = step size*(256*byte1+byte0)
23,24,25 scan holdtime bytes 2,1,0 hold = 65536*byte2+ 256*byte1 +byte0