Spectrum M3i.4830, Руководство по оборудованию

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Trigger modes and appendant registers External (analog) trigger
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Trigger Input Coupling
The external trigger input can be switched by software between AC and DC coupling. Please see the technical data section for details on the
AC bandwidth.
Trigger level
All of the external (analog) trigger modes listed above require at least one trigger level to be set (except SPC_TM_NONE of course). Some
like the window or the re-arm triggers require even two levels (upper and lower level) to be set. The meaning of the trigger levels is depending
on the selected mode and can be found in the detailled trigger mode description that follows.
Trigger levels for the external (analog) trigger to be programmed in mV:
Detailed description of the external analog trigger modes
For all external analog trigger modes shown below, either the OR mask or the AND must contain the external trigger to activate the external
input as trigger source:.
Trigger on positive edge
The trigger input is continuously sampled with the selected
sample rate. If the programmed trigger level is crossed by
the trigger signal from lower values to higher values (rising
edge) then the trigger event will be detected.
This edge triggered external trigger mode correspond to
the trigger possibilities of usual oscilloscopes.
Register Value Direction Description
SPC_TRIG_EXT0_ACDC 40120 read/write A „1“ sets the AC coupling for the external trigger input. A „0“ sets the DC coupling (default)
Register Value Direction Description Range
SPC_TRIG_EXT_AVAIL0_MIN 42340 read returns the minimum trigger level to be programmed in mV
SPC_TRIG_EXT_AVAIL0_MAX 42341 read returns the maximum trigger level to be programmed in mV
SPC_TRIG_EXT_AVAIL0_STEP 42342 read returns the step size of trigger level to be programmed in mV
SPC_TRIG_EXT0_LEVEL0 42320 read/write Trigger level 0 for external trigger -5000 mV to +5000 mV
SPC_TRIG_EXT0_LEVEL1 42321 read/write Trigger level 1 for external trigger -5000 mV to +5000 mV
Register Value Direction Description
SPC_TRIG_ORMASK 40410 read/write Defines the events included within the trigger OR mask of the card.
SPC_TRIG_ANDMASK 40430 read/write Defines the events included within the trigger AND mask of the card.
SPC_TMASK_EXT0 2h Enables the external (analog) trigger 0 for the mask.
Register Value Direction set to Value
SPC_TRIG_EXT0_MODE 40510 read/write SPC_TM_POS 1h
SPC_TRIG_EXT0_LEVEL0 42320 read/write Set it to the desired trigger level in mV mV