HP VXI E1432A manual Measurement initialization

HP E1432A User's Guide

The C-Language Host Interface Library

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 HP E1432A 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 HP E1432A module until the measurement is started with e1432_init_measure. 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 HP E1432A.

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

Tested

Booting

Booted

Settling

Pre-arm

Idle

H

L

L

H

H

L

L

H

Sync/Trigger line

Figure 4-4: Measurement initialization

The module enters the TESTED state after a reset. In this state, all of the module parameters may be set. The HP E1432A stays in the TESTED state until it sees a high-to-low transition of the Sync/Trigger line.

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