INPut Subsystem

The INPut Subsystem configures the input de-bounce circuitry and specifies the input clock source.

Syntax INPutn

: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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INPutn:CLOCk[:SOURce] <source>

Specifies the input circuitry clock source for Port n.

Parameters

Parameter Name

Parameter Type

Range of Values

Default

 

 

 

 

INPutn

numeric

0, 1, 2, 3

0

<source>

discrete

INTernal, EXTernal

INT

 

 

 

 

 

 

 

 

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

46 HP E1459A SCPI Command Reference