HP-UX

NAME

viReadSTB − Reads a status byte of the service request

SYNOPSIS

viReadSTB(ViSession vi, ViPUInt16 status);

Description

 
This function reads a status byte of the service request from a service requester (the message-based device).  For example, on the IEEE 488.2 interface, the message is read by polling devices; for other types of interfaces, a message is sent in response to a service request to retrieve status information.  If the status information is only one byte long, the most significant byte is returned with the zero value.  If the service requester does not respond in the actual timeout period, VI_ERROR_TMO is returned.
 

Parameters

vi An input parameter. Unique logical identifier to the session. 
 

status An output parameter. Service request status byte. 
 
 

Return Values

 
This is the functional return status.  It returns either a completion code or an error code as follows.
 
 

VI_SUCCESS Operation completed successfully. 
 
 

VI_ERROR_INV_SESSION VI_ERROR_INV_OBJECT The given session or object reference is invalid (both are the same value). 
 

VI_ERROR_NSUP_OPER The given vi does not support this function. 
 

VI_ERROR_SRQ_NOCCURRED Service request has not been received for the session. 
 

VI_ERROR_TMO Timeout expired before function completed. 
 

VI_ERROR_RAW_WR_PROT_VIOL Violation of raw write protocol occurred during transfer. 
 

VI_ERROR_RAW_RD_PROT_VIOL Violation of raw read protocol occurred during transfer. 
 

VI_ERROR_BERR Bus error occurred during transfer. 
 

VI_ERROR_NCIC The interface associated with the given vi is not currently the controller in charge. 
 

VI_ERROR_NLISTENERS No Listeners condition is detected (both NRFD and NDAC are deasserted). 
 

AUTHOR

viReadSTB was developed by HP
 

Hewlett-Packard Comapny  —  September 29, 1999