3
System Overview
92
Keysight 34970A/34972A User’s Guide
Main processor
The main processor, located in the floating logic section, controls the input signal
conditioning, ranging, and the ADC. The main processor accepts commands from,
and sends measurement results to, the earth-referenced logic section. The main
processor synchronizes measurements during scanning and control operations.
The main processor uses a multi-tasking operating system to manage the various
system resources and demands.
The main processor also calibrates measurement results, performs Mx+B scaling,
monitors alarm conditions, converts transducer measurements to engineering
units, time stamps scanned measurements, and stores data in non-volatile
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. The instrument automatically scans the list of channels in
ascending order from slot 100 through slot 300. Measurements are taken only
during a scan and only on those channels which are included in the scan list.
You can store up to 50,000 readings in non-volatile memory during a scan.
Readings are stored only during a scan and all readings are automatically time
stamped. Each time you start a new scan, the instrument clears all readings
stored in memory from the previous scan. Therefore, all readings currently stored
in memory are from the most recent scan.
