gpib_write(3)                       CLIX                       gpib_write(3)



  NAME

    gpib_write, gpib_write_nw - Writes data to a General Purpose Interface Bus
    (GPIB) device

  LIBRARY

    Intergraph Device Library (libix.a)

  SYNOPSIS

    #include <sys/xio/xio.h>

    #include <sys/xio/xerr.h>

    int gpib_write(
      int channel ,
      char *ldev ,
      int lcnt ,
      char *dbuf ,
      int dcnt ,
      int timeout ,
      char *eoi ,
      int *xfcnt );

    int gpib_write_nw(
      int channel ,
      char *ldev ,
      int lcnt ,
      char *dbuf ,
      int dcnt ,
      int timeout ,
      char *eoi ,
      struct xiosb *xiosb ,
      int efn );

  PARAMETERS

    channel   An integer representing a GPIB channel

    ldev      A pointer to an array of primary GPIB devices

    lcnt      The number of addresses in ldev

    dbuf      A pointer to the buffer to be transferred

    dcnt      The size of the buffer to be transferred

    timeout   The number of 1/60 second intervals before a GPIB request is
              aborted




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  gpib_write(3)                       CLIX                       gpib_write(3)



    eoi       The GPIB End Or Identify flag

    xfcnt     The number of bytes transferred

    xiosb     A pointer to an xiosb

    efn       The event number associated with the transfer request

  DESCRIPTION

    The gpib_write() function writes data to the General Purpose Interface Bus
    (GPIB) device on channel.  The ldev parameter points to an array of
    primary addresses corresponding to the GPIB devices to receive data.

    The dbuf parameter is a pointer to the buffer to be transferred.  The size
    of the buffer is specified (in bytes) by dcnt.

    The lcnt parameter reflects the number of devices to be initialized as
    listeners before the data transfer begins.  A value of 0 indicates the
    GPIB devices have already been addressed to listen by a previous
    gpib_write().  In this case, the write proceeds without device
    initialization.

    If an abort timeout is desired, timeout contains the number of 1/60 second
    intervals the driver waits before aborting the request.  A value of 0
    disables the timeout mechanism.

    If the value pointed to by eoi is nonzero, the GPIB End Or Identify (EOI)
    signal is asserted during the transfer of the last data byte in the
    buffer.

    Upon completion of the synchronous request, the integer pointed to by
    xfcnt contains the number of bytes transferred from dbuf.

    The gpib_write_nw() function is the asynchronous version of gpib_write(),
    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(3)).  The xfcnt member of the
    xiosb structure indicates the number of bytes transferred from dbuf.

    If a primary address is specified, the controller is put in an active
    state, and the following GPIB messages are sent over the specified
    channel:

    UNL   Unlisten

    UNT   Untalk

    TAG   Talk Address Group




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  gpib_write(3)                       CLIX                       gpib_write(3)



    MLA   My Listen Address

    The system controller is forced to the standby state, and data is written
    to channel until dcnt bytes are transferred.  If primary addresses are not
    specified, the system controller is simply put in a standby state, and the
    write proceeds as described.

  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 gpib_write() and gpib_write_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.

    [GPIB_OUT_OF_RANGE]
           The specified channel is beyond the maximum allowed.

    [GPIB_NOT_OPEN]
           The specified channel is not open.

    [GPIB_NOT_OWNER]
           Channel is currently open by another process.

    [GPIB_CANCELED]
           The current request was canceled by gpib_cancel().

    [GPIB_DEVICE_INVALID]
           A specified device's primary address was not correct.

    [GPIB_TIMEOUT]
           A timeout occurred before the request completed.

    [GPIB_HARDWARE_CHECK]
           A hardware error was detected during the request.

    [BAD_DATA_BUFFER_ADDRESS]
           Either eoi, xfcnt, tdev, or dbuf points to an invalid memory
           address.



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  gpib_write(3)                       CLIX                       gpib_write(3)



    [BAD_DATA_BUFFER_SIZE]
           Either the data transfer size dcnt or the device count lcnt is too
           large.

  RELATED INFORMATION

    Functions:  gpib_open(3), gpib_cmd(3), gpib_cancel(3), intro(3)

    Files:  xgpib(7)













































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