100 Mhz Source Mode; External Source Greater Than 25 Mhz; External Or Internal Source Less Than 25 Mhz - National Instruments X Series User Manual

100 MHz Source Mode

In 100 MHz source mode, the device synchronizes signals on the rising edge of the source, and
counts on the third rising edge of the source. Edges are pipelined so no counts are lost, as shown
in Figure 7-40.

External Source Greater than 25 MHz

With an external source greater than 25 MHz, the device synchronizes signals on the rising edge
of the source, and counts on the third rising edge of the source. Edges are pipelined so no counts
are lost, as shown in Figure 7-41.
External Source >25 MHz

External or Internal Source Less than 25 MHz

With an external or internal source less than 25 MHz, the device generates a delayed Source
signal by delaying the Source signal by several nanoseconds. The device synchronizes signals
on the rising edge of the delayed Source signal, and counts on the following rising edge of the
source, as shown in Figure 7-42.
Figure 7-42. External or Internal Source Less than 25 MHz
Delayed Source
Figure 7-40. 100 MHz Source Mode
100 MHz Source
Synchronize
Figure 7-41. External Source Greater than 25 MHz
Source
Synchronize
X Series User Manual
Count
Count
Synchronize
Count
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