VXI VT1433B manual Parameter Settings, Measurement Initiation, BootingBooted SettlingPre-armIdle

VT1433B User's Guide

Using the VT1433B

Parameter Settings

Many parameters are channel-dependent, meaning that each channel can be set independently of the others in the module. Other parameters are module-dependent; changing a module-dependent parameter for a channel will change it for all channels on that module. For example, changing blocksize, a module-dependent parameter, for input channel 3 will also change the block size for all other channels in the same VT1433B module as channel 3.

When possible, parameters are written to the hardware as soon as they are received. Sometimes, the parameter can’t be written to the hardware until the start of a measurement; in this case the value of the parameter is saved in RAM in the VT1433B module until the measurement is started with hpe1432_initMeasure. Some parameters can be changed while a measurement is running, but many do not take effect until the next start of a measurement.

Measurement Initiation

This section describes the measurement initiation process in the VT1433B.

The measurement initialization states and the corresponding Sync/Trigger line transitions (with ‘H’ for high, ‘L’ for Low) are:

Tested

Booting Booted SettlingPre-arm Idle

H L LH H LLH

Sync/Trigger Line

Figure 3-8: Measurement initialization

The module enters the TESTED state after a reset. In this state, all of the module parameters may be set. The VT1433B stays in the TESTED state until it sees a high-to-low transition of the Sync/Trigger line.

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