User`s guide

Universal Library User's Guide Analog Input Boards - PCM- and PC-CARD-DAS16 Series
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Triggering
PC-Card Only
Trigger functions and methods supported
UL: cbSetTrigger()
UL for .NET: SetTrigger()
Trigger argument values
TrigType TRIGPOSEDGE, TRIGNEGEDGE, GATEHIGH, GATELOW (All at A/D External trigger
input)
Hardware considerations
Pacing analog input
 Internal or external clock
 The packet size is 256 samples for PCM boards; 2048 samples for
PC-CARD boards.
For CONTINUOUS mode scans, the sample count should be at least one packet size (>=2048 samples) for
the PC-CARD- boards.
These cards do not have residual counters, so BLOCKIO transfers must acquire integer multiples of the packet
size before completing the scan. This can be lengthy for the PC-CARDs which must acquire 2048 samples
between interrupts for BLOCKIO transfers. In general, it is best to allow the library to determine the best
transfer mode (SINGLEIO vs. BLOCKIO) for these boards.
Triggering and gating
 External digital (TTL) polled gate trigger supported on PCM versions. Refer to "Trigger support" on
page 29.
 External digital (TTL) hardware trigger supported on PC-CARD versions.