Keithley 6512 Instruction Manual page 47

Table 2-8
Data store reading rates
r Value Rate
0 Conversion Rate (every 360msec)
1 One Reading Per Second
2 One Reading Every 10 seconds
3 One Reading Per Minute
4 One Reading Every 10 Minutes
5 One Reading Per Hour
6 One reading Per Front Panel Trigger
2. To select the desired interval, simply release the ON/
OFF button when the desired rate appears in the display.
The Model 6512 will then begin storing readings at the
selected rate. If you selected the triggered mode, one
reading will be stored in memory each time the front
panel TRIG button is pushed.
(For rapid starts, the rate can be pre-selected by pressing
ON/OFF, releasing the button when the selected rate is
displayed, and then turning off data store. Storage will
then begin at the pre-selected rate the next time the ON/
OFF button is pressed.)
3. When data store memory is full (after all 100 readings
have been stored), the instrument will stop logging data,
and the DATA LED will flash to indicate that memory is
full.
4. Readings can be recalled any time (even if the instru-
ment is still logging) by pressing and holding the RE-
CALL button. Holding the RECALL button in causes
the reading memory location number to be displayed.
Releasing the RECALL button causes the reading at that
location to be displayed. The first data point to be dis-
played will be the last reading stored. For example, if
reading #65 was the last point, the display will show:
5. The second and third points will be the high and low
data points. For example, for the high value, the display
will show:
Similarly, the display will show the following for the
low data point:
n=65
n=HI
n=Lo
6. Following these three points, the remaining data points
will be displayed, beginning with the first one stored.
The memory location will increment from 1 to the max-
imum point stored. For example, the tenth reading ap-
pears as:
7. To continue recalling readings, use the RECALL button
to scroll reading memory locations. Scrolling becomes
more rapid if the RECALL button is held in. Release the
button when the desired data point is displayed.
8. The recall mode can be cancelled simply by pressing
SHIFT RECALL. The instrument will then return to the
normal display mode. As long as data store is not dis-
abled and then re-enabled, readings are retained within
memory. You can return to the recall mode at any time to
review data.
9. To cancel data store operation, press the ON/OFF but-
ton. The ON/OFF LED will turn off, indicating that data
store is disabled. Data is retained until data store is en-
abled once again. Thus, you can still recall data even af-
ter data store is turned off.
Data Store Operating Notes:
1. Data logging continues at the selected rate during recall
until all 100 locations have been filled. Logging stops
when all 100 locations are full, as indicated by the flash-
ing DATA indicator.
2. The data store trigger mode should not be confused with
the front panel trigger mode. The data store trigger mode
is enabled by entering the special trigger parameter
(r=6) at the beginning of the data storage process, while
the front panel trigger mode is entered by pressing
SHIFT TRIG.
3. If the instrument is placed in the front panel one-shot
trigger mode, display readings will be triggered at the
data store rate interval except when r=0. For example, if
the instrument is set up for 10 minute intervals, one
reading will be triggered and displayed every 10 min-
utes. When r=0, a single reading is stored each time an
appropriate trigger is received (for example, GET in the
T3 trigger mode, as described in Section 3).
4. The data store rate can be used to control the data output
rate in the IEEE- 488 talk-only mode. To use the Model
6512 in this manner, place the instrument in the talk-
only mode (see Section 3). Now enter the data storage
mode, and select the desired interval as described above.
Operation
n=10
2-27