National Instruments AT-MIO-16X - Manual (Page 59)

Chapter 2 Configuration and Installation
© National Instruments Corporation 2-37 AT-MIO-16X User Manual
Counter Signal Connections
The general-purpose timing signals include the GATE and OUT signals
for the Am9513A Counters 1, 2, and 5, SOURCE signals for Counters
1 and 5, and the FOUT signal generated by the Am9513A. Counters 1,
2, and 5 of the Am9513A Counter/Timer can be used for
general-purpose applications, such as pulse and square wave
generation, event counting, pulse-width, time-lapse, and frequency
measurements. For these applications, SOURCE and GATE signals can
be directly applied to the counters from the I/O connector. The counters
are programmed for various operations.
The Am9513A Counter/Timer is described briefly in Chapter 3, Theory
of Operation. For detailed programming information, consult
Appendix C, AMD Am9513A Data Sheet. For detailed applications
information, consult the Am9513A/Am9513 System Timing Controller
technical manual published by Advanced Micro Devices, Inc.
Pulses and square waves can be produced by programming Counter 1,
2, or 5 to generate a pulse signal at its OUT output pin or to toggle the
OUT signal each time the counter reaches the terminal count.
For event counting, one of the counters is programmed to count rising
or falling edges applied to any of the Am9513A SOURCE inputs. The
counter value can then be read to determine the number of edges that
have occurred. Counter operation can be gated on and off during event
counting.
Figure 2-17 shows connections for a typical event-counting operation
in which a switch is used to gate the counter on and off.