Grid; Y Hi-Ylo; Rear Panels Features; Externaltrigger - Keithley 595 Instruction Manual

OPERATION
3.4.9 Grid
The grid program allows the user to plot a grid on an HPGL
,compaiible plotter f,HPWOA or equivalent) with the Model
595 acting as a controller. The plotter should be set to ad-
dress 5. The grid will be plotted according to the function,
range and limits the Model 595 is currently set to at the
time the grid is initiated.
After code 42 or 43 has been selected, press the MENU but-
ton until the message "Grid" appears on then display
("Grid" is the thud program on the menu). (NOTE: if no
plotter is actualIy attached at this time, the front panel con-
trols will be inoperable for five seconds while the Model
595 tries to access the plotter). Finally, press either of the
voltage source ADJUST buttons, and the plotter will begin
to draw the grid. The front panel buttons are inoperable
while the grid is being drawn.
3.4.10 Y HI - Y Lo
The Y HI - Y Lo programs are used to set the upper and
lower limits of the Y axis when plotting. The limits run from
+O.l to k2.0 in 0.1 increments, with 2.0 corresponding to
a full 20,000 count display and 0.1 corresponding to 1000
counts. The user can thus adjust Y HI and Y Lo to "crop"
the plot as desired.
After code 42 or 43 has been selected, press the MENU but-
ton until "Y HI 2" appears (or press MENU once more tom
display "Y Jo -2"). To change the program values, press
the voltage source ADJUST buttons. Once the desired limit
is displayed, press SHIFT, then EXIT to leave the menu.
NOTES:
1. The Y axis limit values are not stored in perma-
nent memory and will return to their defaults if power
is cycled to the Model 595.
2. A change~of function, range or voltage limits will affect
the correlation of data to the axis labels.
3.5 REAR PANEL FEATURES
3.5.1 External Trigger
The Model 595 on power up is set to recognize the rear
panel EXTERNAL TRIGGER INPUT. Continuous trigger
or one-shot trigger may be selected by the front panel pro-
gram (see paragraph 3.4.4), or over the IEEE-488 bus. The
commands for external trigger are T6 (continuous) and T7
(one-shot).
The EXTERNAL TRIGGER INPUT requires the falling edge
of a TTL logic level pulse as shown in Figure 3-7. The low
logic level should be between 0 and O.W, and the high level
should be 2.0 to 5.0%'. The minimum pulse width for reliable
triggering is l.O~sec. Connections to the rear panel EXTER-
NAL TRIGGER INPUT jack should be made with a stan-
dard BNC connector.
To use external triggering, proceed as follows:
1~ Ccinnect the external trigger source to the rear panel BNC
EXTERNAL TRIG-GER INPUT connector. The shield
(outer) part of the connector is connected to IEEE com-
mon. There is a-i internal pull-up resistor so a mechanical
switch may be used. Note, however, that debouncing cir-
cuitry will probably be required to avoid improper
tri~ering.
: CAUTION
Do not exceed 30V between IEEE common and
chassis ground, or a shock hazard may be
present.
.ZPlace the instrument in one-shot trigger by pressing
MENU to get into triG, then use either voltage source
ADJUST button to set the display to "triG l'?
3. To trigger the instrument,~~apply a pulse to the EXTER-
NAL TRIGGER INPUT. The instrument will process a
single reading each time the pulse is applied. Alternative-
ly, the instrument may be triggered from the front panel
by pressing SHIFT, then the +I- button.
4. To get out of one-shot, set triG program display back to
0, then press SHIFT then EXIT. A trigger stimulus will
be required to resume continuous measurements.
NOTES:
1. The Model 595 must be set to the appropriates trigger
mode, T6 or T7, to respond to external triggering. Note
that~the instrument is set to T6, Continuous on External
Trigger, on power up.
2. If a trigger overrun occurs (the instrument is triggered
while processing a reading from a previous trigger), it
will ignore the trigger and display: "tErr".
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