Measurements Using Two Pulse Encoders; Buffered (Sample Clock) Position Measurement; Channel Z Reload With X4 Decoding - National Instruments NI cRIO-905x Series User Manual

reload phase becomes true. After the reload occurs, the counter continues to count as before.
The figure below illustrates channel Z reload with X4 decoding.
Max Timebase
Counter Value

Measurements Using Two Pulse Encoders

The counter supports two pulse encoders that have two channels—channels A and B.
The counter increments on each rising edge of channel A. The counter decrements on each
rising edge of channel B, as shown in the following figure.
Figure 70. Measurements Using Two Pulse Encoders
Counter Value 2
For information about connecting counter signals, refer to the
section.

Buffered (Sample Clock) Position Measurement

With buffered position measurement (position measurement using a sample clock), the counter
increments based on the encoding used after the counter is armed. The value of the counter is
sampled on each active edge of a sample clock. The sampled values will be transferred to host
memory using a high-speed data stream. The count values returned are the cumulative counts
since the counter armed event; that is, the sample clock does not reset the counter. You can
route the counter sample clock to the Gate input of the counter. You can configure the counter
to sample on the rising or falling edge of the sample clock.
The figure below shows an example of a buffered X1 position measurement.
84 | ni.com | NI cRIO-905x User Manual
Figure 69. Channel Z Reload with X4 Decoding
Ch A
Ch B
Ch Z
5 6 7
Ch A
Ch B
3
8 9 0 1
A = 0
B = 0
Z = 1
4 5 4
2 3 4
3 4
Default Counter/Timer Routing