The INPut Subsystem configures the input de-bounce circuitry and specifies the input clock source.
Syntax
INPut
n
:CLOCk[:SOURce] <
source>
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:CLOCk[:SOURce]?
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:DEBounce:TIME <
time> | MINimum | MAXimum | DEFault
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:DEBounce:TIME? [MINimum | MAXimum | DEFault]
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INPut
n:CLOCk[:SOURce]
Specifies the input circuitry clock source for Port n.
Parameters
Comments
•
When the clock source is set to INTernal, the input data is sampled by the
internal clock. When the clock is set to EXTernal, the input data is sampled on negative-edge transitions of the input clock.
•
This is the clock source for clocking new data from the optical isolators into
the input circuitry. New data is automatically clocked into the input debounce circuitry for each clock pulse of the internal clock when the clock source is INTernal. Refer to the INPut:DEBounce:TIME command to set the Debounce time.
•
For a clock source of EXTernal, new data is clocked into the input circuitry
when the external clock receives a clock pulse. Data is clocked into the input circuitry on the positive edge of the external clock.
•
Note that the debounce circuitry, current value registers, and event detectors
are always clocked by the internal clock.
•
Note: if a Data Available Event is enabled for the port, attempting to set the
clock source to INTernal will result in an error -221, "Settings Conflict".
•
*RST Condition: sets the input clock source to INTernal.
Example
INP1:CLOC:SOUR EXT
Sets the input clock source for Port 1 to External
