Data Translation DT9857, User Manual, Page: 98 / 192

Chapter 5
98
Using software, specify the counter/timer mode as one-shot, the clock source as internal
(recommended), the clock divider, the polarity of the output pulse (high-to-low transition or
low-to-high transition), and the active gate type (rising edge or falling edge). Refer to
page 94
for more information about pulse output types and to page 93 for more information about
gate types.
Note:
In the case of a one-shot operation, a duty cycle of 100% is set automatically.
Make sure that the signals are wired appropriately. Refer to page 58 for an example of
connecting a one-shot application.
Repetitive One-Shot
Use repetitive one-shot mode to generate a pulse output signal from the counter’s output line
whenever the specified edge is detected on the counter’s gate signal. You can use this mode to
clean up a poor clock input signal by changing its pulse width, and then outputting it.
The module continues to output pulses until you stop the operation. Note that any gate
signals that occur while the pulse is being output are not detected by the module.
The period of the output pulse is determined by the C/T clock source (either internal using a
clock divider, or external). Note that in repetitive one-shot mode, the internal C/T clock is
more useful than an external clock; refer to
page 93 for more information about the C/T clock
sources.
Using software, specify the counter/timer mode as repetitive one-shot, the polarity of the
output pulses (high-to-low transition or low-to-high transition), the C/T clock source as
internal (recommended), the clock divider, and the active gate type (rising edge or falling
edge). Refer to
page 94 for more information about pulse output types and to page 93 for more
information about gates.
Note: In the case of a repetitive one-shot operation, a duty cycle of 100% is set automatically.
Make sure that the signals are wired appropriately. Refer to page 58 for an example of
connecting a repetitive one-shot application.