Dual-Rate: The Pre-Count readings can be measured at one sample

rate; then the Post-Count readings can be measured at another sample rate. The possible sample rate sources occur in pairs. There are four possible pairs:

{EXT1 BNC (pre), EXT2 BNC (post); or vice-versa }

{ECLTRG0 (pre), ECLTRG1 (post); or vice-versa }

{REFERENCE (pre), REFERENCE/N (post)}

{REFERENCE/N (pre), REFERENCE (post)} (N=2,4,10,20,40...4E8).

Timebase and Trigger additional supplemental characteristics

Fixed error in sample 40 psec (record size 32K) time (4.9.1)

Arm Subsystem Each event in this subsystem allows acquisition of one waveform record (i.e., a burst of one or more dual-channel A/D conversions). (Note that in SCPI, each A/D conversion event is a "Trigger".)

Sources: VXI Trigger Busses (TTL and ECL), External BNC, plus

input channel voltage (*). The logical "OR" condition of any two of these sources may be used.

(*) Each channel’s detection circuitry uses two programmed voltage levels,

so that it is possible to generate the arm event when the signal

either enters

or leaves a defined voltage window. Voltage level set

points typically are

accurate to 3% of full-scale and have hysteresis 0.5%

of full-scale.

Rate: when not taking Pre-[Arm]count readings: up to 2M/sec.

when taking Pre-[Arm]count readings: 650 μsec typical

Count: 1 to 65535 or continuous (no pre-arm readings) 1 to 128 (with pre-arm readings)

Delay: Specifies additional programmed time delay from an

arm’s causative event to when the arming actually occurs. This is in addition to irreducible internal delays.

326 Specifications

Appendix A

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Image 326
HP E1429A manual Timebase and Trigger additional supplemental characteristics