National Instruments AT-MIO-16X

Chapter 2 Configuration and Installa tion

National Instruments Corporation 2-41 AT-MIO-16X User Manual

Figure 2-19. General-Purpose Timing Signals

The GATE and OUT signal transitions in Figure 2-17 are referenced to

the rising edge of the SOURCE signal. This timing diagram assumes

that the counters are programmed to count rising edges. The same

timing diagram, with the source signal inverted and referenced to the

falling edge of the source signal, applies to the case in which the counter

is programmed to count falling edges.

The signal applied at a SOURCE input can be used as a clock source by

any of the Am9513A counter/timers and by the Am9513A frequency

division output FOUT. The signal applied to a SOURCE input must not

exceed a frequency of 6 MHz for prop er op er atio n of t h e Am95 13A .

The Am9513A counters can be individually programmed to count rising

or falling edges of signals applied at any of the Am9513A SOURCE or

GATE input pins.

In addition to the signals applied to the SOURCE and GATE inputs, the

Am9513A generates six internal timebase clocks from the clock signal

supplied by the AT-MIO-16X. The base clock signal is selected by a

ttt

SOURCE VIH

VIL

VIH

VIL

sc sp

tgsu tgh

tgw

GATE

tout

OUT VOH

VOL

t145 nsec minimum

sp 70 nsec minimum

gsu 100 nsec minimum

gh 10 nsec minimum

gw 145 nsec minimum

out 300 nsec maximum