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Chapter 7
Counters
Refer to the following sections for more information about the M Series edge-separation
measurement options:
•
Single Two-Signal Edge-Separation Measurement
•
Buffered Two-Signal Edge-Separation Measurement
Single Two-Signal Edge-Separation Measurement
With single two-signal edge-separation measurement, the counter counts the number of rising
(or falling) edges on the Source input occurring between an active edge of the Gate signal and
an active edge of the Aux signal. The counter then stores the count in a hardware save register
and ignores other edges on its inputs. Software then reads the stored count.
Figure 7-20 shows an example of a single two-signal edge-separation measurement.
Figure 7-20.
Single Two-Signal Edge-Separation Measurement
Buffered Two-Signal Edge-Separation Measurement
Buffered and single two-signal edge-separation measurements are similar, but buffered
measurement measures multiple intervals.
The counter counts the number of rising (or falling) edges on the Source input occurring between
an active edge of the Gate signal and an active edge of the Aux signal. The counter then stores
the count in a hardware save register. On the next active edge of the Gate signal, the counter
begins another measurement. A DMA controller transfers the stored values to host memory.
Figure 7-21 shows an example of a buffered two-signal edge-separation measurement.
Figure 7-21.
Buffered Two-Signal Edge-Separation Measurement
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Summary of Contents for PCI-6281
Page 1: ...PCI 6281...
