Keithley 2750 User Manual page 215

7-10 Scanning
SCAN operation — When a scan is started, one or more complete scans will be per-
formed. The number of channels in the scan list determines the number of channels for
each scan. The reading count determines the number of scans to perform and is best
explained by an example. Assume there are 10 channels in the scan list. If you set the read-
ing count to 10 or less, one scan of the 10 channels will be performed. If you set the read-
ing count to any value from 11 to 20, two scans will be performed. A reading count from
21 to 30 gives you three scans, and so on.
If the reading count is set to infinity (INF), the scan will continuously repeat until you
stop it.
NOTE
Output trigger
STEP operation — After each channel is scanned, an output trigger is applied to the rear
panel Trigger Link connector.
SCAN operation — After all channels in the scan list are scanned, an output trigger is
applied to the rear panel Trigger Link connector.
As shown in Figure 7-2, two counters are used for SCAN operation. The Trigger
counter controls the number of scans, and the Sample Counter controls the num-
ber of channels for each scan. The number of channels in the scan list and the
programmed reading count automatically sets the Trigger Counter and the Sam-
ple Counter.
The Sample Count is equal to the scan list length. For example, if channels 101,
102, and 103 are programmed to be scanned, the Sample Count is 3.
Model 2750 Multimeter/Switch System User's Manual