Recallingdata; Analogoutput - Keithley 486 Instruction Manual

SECI'ION3
Front Panel Operation
previous paragraph. Only the trigger setup is different.
The trigger mode is set for one-shot (TRIG MODE ONE-
SHOT), and the trigger source is set for external U'RG
SCR EXTERNAL) or operate U-RG SRC OPERATE).
In the one-shot mode, each press of the TRIGGER key
will cause a single reading to be processed and stored in
thebuffer.ThefTontpanelTRIGGERkeyisactiveregard-
less of the trigger source sekxiion. With the external big-
ger source selected (TRIG SRC EXTERNAL), each trigger
pulse applied to the unit (see paragraph 3.9.4) will proc-
ess and store a single reading. With the operate trigger
source selected (TRIG SRC OPERATE), a single reading
will be processed and stored each time the Model 487 V-
Source is placed in operate.
NOTES:
1.
2.
Trigger interval cannot be set when in the one-shot
trigger mode.
Triggerdelay can besetintheoneshottriggermode.
Each time the trig@r stimuh.~~ occurs, the reading
and storageprocesswillnot occuruntilthedelayha
expired.Anytriggersthatoccurduringthedelaype-
riod will result in a trigger overrun error URG
OVERUS. The invalid trigger(s) will be ignored.
3.11.3 Recalling Data
Data can be recalled either during storage or after storage
is complete by using the following procedure:
Press and release MENUuntil data recall is selected,
and use the rotary knob or the <and> keys to display
the following message:
DATARECL YES
PressMENUThereadingstoredinthefirstmemory
location will be displayed. For example, if a 1mA
reading is stored in location 001, the following mes-
sage will be displayedz
1.ooom mA Lot 001
For sequential access, use the rotary knob. Turning
the knob cow.ter-&xkwise will display the maxi-
mum (LOC MAX) and minimum readings stored in
thebuffer.Turrdngtherotaryknob clockwisewillin-
crement buffer locations until the last buffer location
is reached.
4.
5.
To access a reading at a particular memory location,
use the4 and, keys to position the cursor on the de-
sired digit and use the rotary knob to adjust the loca-
tion value from the selected digit.
To
exit
data recall, press SHIFT and then EXIT.
NOTES:
1. If the data store has no valid data to display, the fol-
lowing message will appear in the small display
upon entry into data recall:
NO DATA
2. The instrument will continue to store data while in
data recall until the data store buffer is full (unless in
wrap-around operation).
3.12 ANALOG OUTPUT
The Model 486/487 has a non-inverting ZV analog out-
put. ANALOG OUTPUT connections are shown in
Figure 3-14. For a ZOO,CPXI count input, the analog output
will be ZV. Typical examples are shown in Table 3-9.
The output resistance of the analog output is lOOR. To
minimize the effects of loading, the input impedance of
the device connected to ANALOG OUTPUT should be as
high as possible. For example, for a device with an input
impedance of IOkQ, the error due to loading will be ap-
proximately 1%. Rel has no effect on the analog output. A
1mA input (2mA range) will result in a 1v analog output
whether Rel is enabled or not.
CAUTION
To prevent damage to the imtmnent, ad-
here to the following precautions when
floating the input above chassis ground:
1. Do not connect ANALOG OUTPUT LO
to CHASSIS. If there is a ground link in-
stalled at the rear panel binding posts, re-
move it.
2 Make sure that any monitoring ins&u-
ment connected to the analog output is float-
Paragraph 3.16.8 explains the precautions for
floating measurements in more detail.
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