pdi_read(3)                         CLIX                         pdi_read(3)



  NAME

    pdi_read, pdi_read_nw - Read data from a Processed Data Interface port
    into memory

  LIBRARY

    Intergraph Device Library (libix.a)

  SYNOPSIS

    #include <sys/xio/xerr.h>

    #include <sys/xio/xio.h>

    int pdi_read(
      int channel ,
      char *dbuf ,
      int dcnt ,
      int timeout ,
      int *xfcnt );

    int pdi_read_nw(
      int channel ,
      char *dbuf ,
      int dcnt ,
      int timeout ,
      struct xiosb *xiosb ,
      int efn );

  PARAMETERS

    channel   An integer representing a Processed Data Interface port

    dbuf      A pointer to a data buffer

    dcnt      The size of the data buffer

    timeout   The time limit in 1/60 second intervals for the data transfer

    xfcnt     The number of bytes transferred

    efn       The event flag number associated with the request

    xiosb     A pointer to the xiosb structure updated upon completion of the
              request

  DESCRIPTION

    The pdi_read() and pdi_read_nw() functions provide a mechanism for reading
    directly from the Processed Data Interface (PDI) port on the Image System



  2/94 - Intergraph Corporation                                              1

  pdi_read(3)                         CLIX                         pdi_read(3)



    Interface (ISI) board referenced by channel.  The channel must have been
    opened with pdi_open().

    The dbuf parameter points to the data buffer.  The buffer must begin on a
    longword boundary.  The dcnt parameter contains the byte count to be
    transferred and must be a multiple of the linewidth specified in
    pdi_setup().

    The timeout parameter indicates the time limit in 1/60 second intervals
    for the data transfer.  Any transfer that takes longer is aborted and an
    appropriate status is returned.  A timeout value of 0 disables the timeout
    function.

    Upon completion of the synchronous request, xfcnt indicates the number of
    bytes transferred.

    The pdi_read_nw() function is the asynchronous version of pdi_read(),
    providing the same capability without waiting for completion of the
    request.  The efn parameter is the event flag number associated with the
    request.  The xiosb parameter is a pointer to the xiosb structure updated
    upon completion of the request (see intro).  The xfcnt member of the xiosb
    structure indicates the number of bytes transferred.

  RETURN VALUES

    Upon successful completion of the synchronous request, a value of 0 is
    returned.  Otherwise, one of the following failure codes is returned.

    If the asynchronous request is accepted by the XIO system, a value of 0
    will be returned by the request.  Otherwise, XIO_FAILURE will be returned.
    Upon completion of an accepted request, the status member of the xiosb
    structure will be set to either 0 if successful, or to one of the
    following failure codes if unsuccessful.

  ERRORS

    The pdi_read() and pdi_read_nw() functions will fail if one of the
    following is true:

    [XIO_FAILURE]
           The system does not contain the driver needed to support this
           request or efn is invalid.

    [ISI_CHANNEL_NOT_OPEN]
           The specified channel is not open for this process.

    [BAD_DATA_BUFFER_ADDRESS]
           The data buffer is not longword aligned or points to a nonwritable
           memory address.

    [BAD_DATA_BUFFER_COUNT]



  2                                              Intergraph Corporation - 2/94

  pdi_read(3)                         CLIX                         pdi_read(3)



           The byte count is not a multiple of linewidth from pdi_setup().

    [PAGE_LOCK_FAILED]
           Not enough physical memory for this request is available at this
           time.

    [ISI_CANCELED]
           The request was canceled with pdi_cancel() or pdi_close().

    [ISI_PARITY_ERROR]
           A parity error occurred on the transfer.

    [ISI_CYCLE_ERROR]
           A hardware handshake error occurred on the transfer.

    [ISI_TIMEOUT]
           The timeout expired before the transfer completed.

  RELATED INFORMATION

    Functions:  pdi_open(3), pdi_close(3), pdi_setup(3), pdi_cancel(3),
    intro(3)

    Files:  xpdi(7)






























  2/94 - Intergraph Corporation                                              3