[SENSe[<chan >]]:SWEep

The SENSe:SWEep commands select how many readings will be taken during a measurement, and how many of the readings occur before (pre-arm) and after (post-arm) the arm event.

Since the triggering and timebase circuits of the HP E1429 are shared between both sensing channels, the settings for [SENSe[<chan>]]:SWEep are the same for both values of chan (1 and 2). Setting SENSe1:SWEep values will also set SENSe2:SWEep values and vice versa.

Memory Usage Measurements which specify multiple bursts (ARM:STARt:COUNt > 1) of both pre-arm and post-arm readings (SENSe:SWEep:OFFSet:POINts -3 with SENSe:SWEep:POINts > 9) cause memory to be partitioned into segments to hold each burst of readings. The HP E1429 will automatically allocate ARM:STARt:COUNt memory partitions large enough to hold the specified number of pre-arm and post-arm readings. Since a large number of pre-arm readings may occur before the arm event causes post-arm readings to be taken, each memory partition is treated like a circular buffer where pre-arm readings may "wrap" or overwrite each other multiple times before the arm event occurs and the burst of readings completes with the post-arm readings being taken. After all post-arm readings have been taken in a partition, if ARM:STARt:COUNt is not yet satisfied, the instrument directs the next burst of readings into the next memory partition.

Note There is a time window of typically 630 μs where pre-arm readings will be lost while the HP E1429 arranges for readings to be directed into the next memory partition. If an ARM event (ARM:STARt:SOURce) or TRIGger event (sample) occurs during this time window, it will be ignored with no error reported.

[SENSe[<chan >]]:SWEep Subsystem

Command Reference 257

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Image 257
HP E1429A manual SENSechan SWEep