Stanford Research Systems SR620, Руководство пользователя

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Programming Commands 31
SR620 Universal Time Interval Counter
MTRG j
The MTRG command is equivalent to pushing the
manual trigger button and only functions when the
unit is in an external arming mode. In the external
gate modes the parameter j = 1 starts the gate and
j = 0 stops the gate. Otherwise the value of j is
ignored.
The MTRG command has no effect if a
measurement has not been started ( a STRT
command, or front panel button push ), or is the
SR620 is in holdoff at the end of a scan point.
RLVL (?) {j}
The RLVL command sets the amplitude of the
front panel reference output. The parameter j = 0
selects ECL output while j = 1 selects TTL output.
TCPL (?) i {,j}
The TCPL command sets the ac/dc coupling of the
channel A and B inputs. The parameter j = 0
selects dc while j = 1 selects ac.
TERM (?) i {,j}
The TERM command selects the input termination
of the EXT, A, and B inputs. The parameter j = 0
selects 50 Ohm termination while j = 1 selects 1
Mohm termination. Also, in frequency and period
modes, the value j = 2 selects the UHF prescalers
( the 50 ohm terminator is automatically selected
with the prescalers).
TMOD (?) i{,j}
The TMOD command selects the trigger mode of
the A and B inputs. The parameter j = 0 selects
normal mode while j = 1 selects autolevel mode.
Once autolevel is selected it will remain in effect
until the level is set by the LEVL command, it is
turned off by the TMOD command, or the front
panel knob is rotated.
TSLP (?) i{,j}
The TSLP command selects the trigger slopes of
the EXT, A, and B inputs. The parameter j = 0
selects positive slope while j = 1 selects negative
slope.
Measurement Control Commands
*TRG
The *TRG command is the device trigger common
command. It functions identically to the STRT
command and to pushing the front panel "START"
button.
ARMM (?) {j}
The ARMM command selects the SR620's arming
mode. The parameter j sets the mode according
to the following table. The measurement modes in
which a particular type of arming is allowed is also
shown
j arming
mode measurement modes
0 ±time
time
1 +time time, width,rise/fall
time, phase
2 1 period frequency, period
3 0.01s gate frequency, period,
count
4 0.1s gate frequency, period,
count
5 1.0s gate frequency, period,
count
6 ext trig +- time time
7 ext trig +time time, width, rise/fall
time, phase
8 ext gate/+ time/hldf time, width,
frequency, period,
count
9 ext triggered 1 period frequency, period
10 ext triggered .01s gate frequency, period,
count
11 ext triggered 0.1s gate frequency, period,
count
12 ext triggered 1.0s gate frequency, period,
count
Use of the scanning internal gate requires that the
unit be in arming mode 6,7, or 8.
AUTM (?) {j}
The AUTM command sets the auto measurement
mode. The parameter j = 1 sets the AUTO mode
"ON" and the SR620 will automatically start a new
measurement of N samples when the old one is
complete. The parameter j = 0 sets the AUTO
mode "OFF" and requires an individual command
to start each measurement. It is recommended
that auto measurement be OFF if a computer is
being used to take data as this allows