Keithley KPCI-3101 Series, Руководство пользователя

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2-28 Principles of Operation KPCI-3101 — KPCI-3104 Series User’s Manual
Figure 2-16 shows an example of performing an enabled rate generation operation using an
external C/T clock source with an input frequency of 4kHz, a clock divider of 4, a low-to-high
pulse type, and a duty cycle of 75%. (The gate type does not matter for this example.) A 1kHz
square wave is the generated output.
Figure 2-17 shows the same example using a duty cycle of
25%.
Figure 2-16
Example of rate generation mode with a 75% duty cycle
Figure 2-17
Example of rate generation mode with a 25% duty cycle
One-Shot
Use one-shot mode to generate a single pulse output signal from the counter when the operation
is triggered (determined by the gate input signal). You can use this pulse output signal as an
external digital (TTL) trigger to start other operations, such as analog input or an external
instrument.
When the one-shot operation is triggered and a single pulse is output; then, the one-shot opera-
tion stops. All subsequent clock input signals and gate input signals are ignored.
Pulse
Output
Signal
75% duty cycle
Rate Generation
Operation Starts
External C/T
Clock
Input Signal
(4kHz)
Pulse
Output
Signal
25% duty cycle
Continuous Pulse
Output Operation Starts
External C/T
Clock
Input Signal
(4kHz)