PPoll
Purpose
Perform a parallel poll on the GPIB.
Format
C
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void PPoll (int boardID, short *result)
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Visual Basic
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CALL PPoll (boardID%, result%)
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Input
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boardID
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The interface number |
Output
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result
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The parallel poll result |
Description
PPoll conducts a parallel poll and the result is placed in result. Each of the eight bits of result represents the status information for each device configured for a parallel poll. The interpretation of the status information is based on the latest parallel poll configuration command sent to each device (see PPollConfig and PPollUnconfig). The Controller can use parallel polling to obtain one-bit, device-dependent status messages from up to eight devices simultaneously.
For more information about parallel polling, refer to the Parallel Polling Overview.
Possible Errors
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EARG
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result does not point to a valid memory location. |
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ECIC
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The interface is not the Controller-In-Charge; see SendIFC. |
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EDVR
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The NI-488.2 driver is either configured incorrectly or is not properly installed. |
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EHDL
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boardID is out of range. |
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ELCK
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The requested operation could not be performed because of an existing lock by another process. |
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ENEB
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The interface is not installed or is not properly configured. |
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EOIP
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Asynchronous I/O is in progress. |