nvrd(7)                        DG/UX 5.4R3.00                        nvrd(7)


NAME
       nvrd - AViiON family non-volatile disk subsystem

SYNOPSIS
       nvrd([vmebus,][def]) or
       nvrd@devicecode([vmebus,][[[cr-addr],mem-addr],size])

DESCRIPTION
       The nvrd disk subsystem consists of the set of VME-based non-volatile
       RAM boards which supports the following units:

       Model #  Size
       5018VME  2 Mbyte Special Systems ECC non-volatile memory board
       xxxx

       The nvrd entry has two formats (shown above and illustrated below).
       The first format accepts all defaults for a specified controller
       board.  The second format specifies all values:

       vmebus        The device name of the parent VME bus to which the
                      nvrd controller is attached, such as vme(0) or vme(1).
                      If this parameter is omitted, a parent bus of vme(0)
                      is assumed, and all subsequent parameters move up one
                      position.  Thus, nvrd(3) is equivalent to
                      nvrd(vme(0),3).

       def            A number from 0 to 7, or null for 0, identifying the
                      controller board defaults to use

       @devicecode   The controller device code, preceded by the @
                      character

       cr-addr        The address of the device's control registers.

       mem-addr       The address of the device's non-volatile memory.

       size           The number of megabytes of non-volatile memory on the
                      device (default is 2).

       The nvrd provides a physical disk interface to the board.  A physical
       disk unit may be accessed directly via the special file nodes in
       /dev/pdsk and /dev/rpdsk.  These nodes are found in /dev/[r]pdsk and
       are named according to the long format specified above.

       The nvrd subsystem has 8 built-in defaults for the device code,
       control register address, memory address, and size.  When using the
       defaults, the following short form of the nvrd device specification
       can be used:

           nvrd(number)

       where number identifies the following corresponding long form of the
       device.




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nvrd(7)                        DG/UX 5.4R3.00                        nvrd(7)


           Short Form      Device Code/Control/Memory/Size

           nvrd(0)         0x80/0xFFFFFF00/0xE5000000/2
           nvrd(1)         0x82/0xFFFFFF20/0xE5200000/2
           nvrd(2)         0x84/0xFFFFFF40/0xE5400000/2
           nvrd(3)         0x86/0xFFFFFF60/0xE5600000/2
           nvrd(4)         0x88/0xFFFFFF80/0xE5800000/2
           nvrd(5)         0x8A/0xFFFFFFA0/0xE5A00000/2
           nvrd(6)         0x8C/0xFFFFFFC0/0xE5C00000/2
           nvrd(7)         0x8E/0xFFFFFFE0/0xE5E00000/2

       The entries in the above table skip a set of device codes and control
       register addresses in the long form of the device.  The reason for
       this is the support of mirrored boards.  Each of the above eight
       configurations for the nvrd can run mirrored.  This is done by
       setting the DIP switches for the device code, control register
       address, and memory address to the above settings.  This board is
       considered the master and is the only board in a mirrored pair that
       is configured.  The slave board, which is not configured, must have
       its DIP switches set to values that correspond to the master board.
       The correspondence is the following:

           device-code     should be set to one greater on the slave board.
           cr-address      should be set to 0x10 greater on the slave board.
           memory-address  should be identical on the slave board.

           DIP Switches    Master    Slave

           device code     80        81
           cr-address      FFFFFF00  FFFFFF10
           memory-address  E5000000  E5000000

       If one of the boards in a mirrored pair fails, a message will be sent
       to the system console and logged.  Because the boards are mirrored,
       no application using the boards will notice the failure.  To avoid
       the loss of data if a failure of one of the boards occurs, the
       following instructions must be applied.

       If the board that failed is the slave board, then it can be repaired
       or replaced with the same DIP switch settings.  If the board that
       failed is the master board, then the slave board must have its DIP
       switch settings set to the master.  The master board must be repaired
       or replaced with its DIP switch settings set to the previous slave's
       settings.

       The nodes in /dev/pdsk provide access as a block special device as
       described in dsk(7).  The nodes in /dev/rpdsk provide access as a
       character special device as described in rdsk(7).  When accessing a
       disk through a /dev/pdsk or /dev/rpdsk node, the operating system
       performs no bad block remapping.

FILES
       /dev/pdsk/*




Licensed material--property of copyright holder(s)                         2

nvrd(7)                        DG/UX 5.4R3.00                        nvrd(7)


       /dev/rpdsk/*

SEE ALSO
       vme(7), dsk(7), rdsk(7).





















































Licensed material--property of copyright holder(s)                         3