Chapter 9

Counters

the signal goes high or vice versa. For continuous pulse generations, the counter stops generating pulses while the external trigger signal is low and resumes when the signal goes high or vice versa.

When using a pause trigger, the pause trigger source is routed to the

Counter n Gate signal input of the counter.

Other Counter Features

Sample Clock

When taking counter measurements, you can enable a sample clock. When you use a sample clock, measurements are saved after an active edge of the sample clock. Figure 9-29shows an example of using a sample clock with a buffered period measurement. In this example, a period is defined by two consecutive rising edges of the Gate.

 

Counter Armed

 

 

 

 

 

 

 

 

 

GATE

 

 

 

 

 

 

 

 

 

 

SOURCE

 

 

 

 

 

 

 

 

 

 

COUNTER VALUE

 

1

2

3

4

1

2 1

2

3

1

SAMPLE CLOCK

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

4

4

 

 

 

4

BUFFER

 

 

 

 

 

 

 

 

 

3

 

 

 

 

 

 

 

 

 

 

TIME N

t0

t1

 

t2

t3

 

t4

 

t5

 

Figure 9-29.Sample Clock Example