xcsi(7)                             CLIX                             xcsi(7)



  NAME

    xcsi - Control Status Interface

  DESCRIPTION

    The xcsi interface is a DR11-based communication interface that uses the
    Control Status Interface (CSI) port that resides on the Image System
    Interface (ISI) board.  The ISI board may reside on the Shared Resource
    (SR) bus of Intergraph 300- and 400-series workstations and servers.  The
    xcsi interface is used for high-speed transfer of command and status
    packets between the workstation and various special-purpose hardware.

    The hardware is a subset of the standard DR11 interface.  The xcsi
    interface defines a protocol that uses the DR11 function and status lines
    along with the attention interrupts.  The workstation is a master and can
    only support connections to slave DR11 devices.  In addition,
    communication depends on a standard header common to all command and
    status packets.  The header indicates the source and destination of each
    packet, along with packet size and validity checking information.  The
    definition of this header is in <sys/xio/xcsi.h> and its fields are shown
    below:

    short h_cmd;      /* CSI command/status ID */
    short h_mswcnt;   /* MSW of command size */
    short h_lswcnt;   /* LSW of command size */
    short h_src;      /* source ID */
    short h_dest;     /* route code */
    short h_magic0;   /* 0x5555 sanity check */
    short h_magic1;   /* 0xaaaa sanity check */
    short h_seq0;     /* relative start time */
    short h_seq1;     /* relative finish time */
    short h_checksum; /* header checksum sanity check */

    Each ISI board supports a single CSI port.  The CSI port on the ISI board
    in the lowest SR slot number is referred to as channel 0.  The next ISI
    board supports channel 1 and so forth.  Each xcsi channel may be opened
    and used by many processes at a time.

    To send commands to the CSI port, use csi_cmd() specifying a currently
    open channel from csi_open().  Incoming status packets are matched with
    outgoing commands based on command ID and source/route codes.  Refer to
    csi_dstat() for commands that may respond with multiple status packets.
    If the slave device needs special attention, it may send an unsolicited
    status packet.  Refer to csi_ustat() for information on intercepting these
    packets.  Refer to csi_death() to monitor hardware problems at run time.

  RELATED INFORMATION

    Functions:  csi_cancel(3), csi_ccan(3), csi_close(3), csi_cmd(3),
    csi_death(3), csi_dstat(3), csi_open(3), csi_reset(3), csi_status(3),



  2/94 - Intergraph Corporation                                              1

  xcsi(7)                             CLIX                             xcsi(7)



    csi_ucan(3), csi_ustat(3)





















































  2                                              Intergraph Corporation - 2/94