Agilent Technologies 34970A manual Scanning

Chapter 3 System Overview

Measurement Input

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.

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