Introduction to the 34980A
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Keysight 34980A Mainframe User’s Guide
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Main System Processor
The main system processor controls the input signal conditioning, ranging, the
ADC, and all backplane transactions. The main system processor synchronizes
measurements during scanning and control operations. The main system
processor uses a multi-tasking operating system to manage the various system
resources and demands.
The main system processor also performs Mx+B scaling operations, monitors
alarm conditions, converts transducer measurements to engineering units, adds
time stamp information to scanned measurements, and stores measurement data
in memory.
Scanning
The instrument allows you to combine a DMM (either internal or external) with
multiplexer channels to create a scan. During a scan, the instrument connects the
DMM to the configured multiplexer channels one at a time and makes a
measurement on each channel.
Before you can initiate a scan, you must set up a scan list to include all desired
multiplexer or digital channels. Channels which are not in the scan list are skipped
during the scan. By default, the instrument automatically scans the list of
channels in ascending order from slot 1 through slot 8 (channels are reordered as
needed). If your application requires non-ordered scanning of the channels in the
present scan list, you can configure a non-sequential scan. Measurements are
taken only during a scan and only on those channels which are included in the
scan list.
You can store up to 500,000 readings in memory during a scan and all readings
are automatically time stamped. The most recent readings are always preserved in
memory. You can read the contents of memory at any time, even during a scan.
Reading memory is not cleared when you read it. Each time you start a new scan,
the instrument clears all readings stored in reading memory from the previous
scan. Therefore, all readings currently stored in memory are always from the most
recent scan.
You can configure the event or action that controls the onset of each sweep
through the scan list (a sweep is one pass through the scan list):
– You can set the instrument's internal timer to automatically scan at a specific
interval as shown below.
