National Instruments AT E Series

Chapter4 ConnectingSignals

©NationalInstruments Corporation 4-37 ATE Series User Manual

Figure4-20. STARTSCANOutput Signal Timing

The CONVERT*pulses are masked off until the device generates the

STARTSCANsignal. If you are using internally generated conversions,

the firstCONVERT* appears when the onboard sample interval counter

reacheszero. If you select an external CONVERT*, the first external pulse

after STARTSCANgenerates a conversion. The STARTSCANpulses

should be separated by at least one scanp eriod.

Acounter on the AT E Series device internally generates the STARTSCAN

signalunless you select some external source. This coun ter is started bythe

TRIG1 signal and is stopped either bysoftware or by the sample counter.

Scansgenerated by either an internal or external STARTSCAN signal are

inhibitedunless they occur within a DAQ sequence. Scans occurring within

aDAQ sequence may be gated by either the hardware (AIGATE)signal or

softwarecomma nd registergate.

STARTSCAN

a.Start of Scan

tw=50to100ns

Start Pulse

CONVERT*

STARTSCAN

b.Scan in Progress, TwoConversions per Scan

toff= 10 ns minimum toff