Spectrum M2p.59 Series Hardware Manual page 105

Trigger modes and appendant registers
Trigger on positive and negative edge
The trigger input is continuously sampled with the selected
sample rate. If the programmed trigger level is crossed by
the trigger signal (either rising or falling edge) the trigger
event will be detected.
This edge triggered external trigger mode correspond to
the trigger possibilities of usual oscilloscopes.
Register
SPC_TRIG_EXT0_MODE
SPC_TRIG_EXT0_LEVEL0
High level trigger
This trigger mode will generate an internal gate signal that
can be useful in conjunction with a second trigger mode to
gate that second trigger. If using this mode as a single trigger
source the card will detect a trigger event at the time when
entering the high level (acting like positive edge trigger) or if
the trigger signal is already above the programmed level at
the start it will immediately detect a trigger event.
The trigger input is continuously sampled with the selected
sample rate. The trigger event will be detected if the trigger
input is above the programmed trigger level.
Register
SPC_TRIG_EXT0_MODE
SPC_TRIG_EXT0_LEVEL0
Low level trigger
This trigger mode will generate an internal gate signal that
can be useful in conjunction with a second trigger mode to
gate that second trigger. If using this mode as a single trigger
source the card will detect a trigger event at the time when
entering the low level (acting like negative edge trigger) or if
the trigger signal is already above the programmed level at
the start it will immediately detect a trigger event.
The trigger input is continuously sampled with the selected
sample rate. The trigger event will be detected if the trigger
input is below the programmed trigger level.
Register
SPC_TRIG_EXT0_MODE
SPC_TRIG_EXT0_LEVEL0
Value Direction set to
40510 read/write SPC_TM_BOTH
42320 read/write Set it to the desired trigger level in mV
Value Direction set to
40510 read/write SPC_TM_HIGH
42320 read/write Set it to the upper trigger level in mV
Value Direction set to
40510 read/write SPC_TM_LOW
42320 read/write Set it to the upper trigger level in mV
(c) Spectrum Instrumentation GmbH
Main analog external trigger (Ext0)
Value
4h
mV
Value
00000008h
mV
Value
00000010h
mV
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