A:\WIN_NT\INTEL3_5\README.TXT       DATECODE:110394             PAGE 1 OF 4

   Digital Equipment Corporation -

   The following driver kit files are a Copyright of Digital Equipment
   Corporation:

       DC21040.SYS
       OEMSETUP.INF
       README.TXT

    +-------------------------------------------------------------------+
    |       DC21040 driver for Intel [tm] Windows NT [tm] 3.5           |
    |                    - Version V6.1 -                               |
    +-------------------------------------------------------------------+

   I. Installing the DE425 EISA Ethernet Adapter
   ----------------------------------------------

   1. Plug the board in a EISA slot

   2. Run the EISA System Configuration Utility
      (ECU)

   3. In the EISA System Configuration,
       select the [Configure computer] option

   4. Insert a floppy with the DE425 EISA configuration
      file !DEC4250.CFG

   5. In the main menu, select the [Save and exit] option
      to complete the initialization.

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   III. Installing the DC21040 driver for Windows NT [tm]
   -------------------------------------------------------

   1. Open the Windows NT [tm] Networks Control Program Applet (NCPA)
      from inside the Window Control Panel.

   2. Click on [Add_Adapter]

   3. Select [<Other> Requires disk from the manufacturer]
      in the Add Network Adapter box

   4. Insert the DC21040 driver kit floppy in the floppy drive

   5. Select your option
    
             [DEC DE425 EISA Ethernet Adapter        ]

      from the Select OEM Option box

      (Choose the first option DEC DC21040 for on_board
       DC21040 controller)

   6. Modify the default distribution path in the Windows NT [tm]
      Setup box to point to the floppy drive if your floppy
      drive is not drive A: then click on [Continue]

   7. For  PCI options, a Dialog box pops up to select the:
 
      ConnectionType:

         o AutoDetection               In AutoDetection mode the driver
                                       checks first the Twisted Pair port. 
                                       If the Link Test fails the driver 
                                       checks to AUI Thinwire. If not carrier 
                                       is detected  the driver switches to 
                                       AUI Thickwire.
         o Twisted Pair 
 
         o Twisted Pair-Full Duplex    To connect to Full Duplex hubs
 
         o Twisted Pair-No Link Test   To connect hubs not supporting 
                                       the Link Integrity Test
         o AUI-Thinwire                BNC connector

         o AUI-Thickwire               15_pin connector

   8. Upon completion, one of the following adapters

             [ [n]DEC DE425 EISA Ethernet Adapter        ]

      appears in the Installed Adapter Cards list of the
      Network Setting box (n is the adapter number).

   9. Click on [Close] to complete the Network Setting
      initialization.
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   10. To overwrite the initial values set by the EISA Configuration
       Utility (ECU) or the driver default values, add or edit the 
       following values in the Registry DC21040_<adapter_number> Parameters 
       subtree:
          NetworkAddress = REG_SZ { xx-xx-xx-xx-xx-xx }

                  Mandatory if no Serial ID PROM is plugged in
                  Overwrite the Serial ID PROM if plugged in
                  NetworkAddress 00-00-00-00-00-00 is ignored

        SoftwareCRC = REG_DWORD { 0 |  1 }  (rev 1.x, 2.0 & 2.2 only)

                  0 The CRC is generated by the adapter
                  1 (default) The CRC is generated by software for 
                    transmit packets bigger than the transmit threshold. 

                  NOTE: This option affects performances and could be 
                        disabled if the adapter does not report transmit 
                        underflows in its statistic counters

       The following values allow to overwrite the DC21040 default setting.
       Refer to the DC21040 Engineering specifications for 
       detailled description

          BurstLength = REG_DWORD  { 1 | 2 | 4 | 8 | 16 | 32 }

                         CSR0<PBL>  1  doubleword
                                    2  doublewords
                                    4  doublewords
                                    8  doublewords    
                                   16  doublewords   (default)
                                   32  doublewords   (not DC21040 rev1)

          FifoArbitration = REG_DWORD { 0 | 1 }

                        CSR0<BAR>   0 Rcv/Txm Arbitration (default)
                                    1 Round_Robin

          StopBackoffCounter = REG_DWORD { 0 | 1 }  (not DC21040 rev1)

                        CSR6<SB>    0  Disabed (Default)
                                    1  Enabled

          BackPressure = REG_DWORD { 0 | 1 }  (not DC21040 rev1)

                        CSR6<BP>    0  Disabed (default)
                                    1  Enabled

           CaptureEffect = REG_DWORD { 0 | 1 }  (not DC21040 rev1)

                        CSR6<CA>    0  Disabed (Default)
                                    1  Enabled

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      These Registry values can be edited interactively through the Registry
      editor (winnt\system32\regedt32.exe) or by invoking the regini command
      Edit an DC21040.ini file as described below, then invoke the command:

      regini DC21040.ini

      DC21040.ini format:

       \Registry\Machine
           System
              CurrentControlSet
                 Services
                     dc21040_{adapter_number}
                         Parameters

                            {valuename} = {type}{value}


   11. Shutdown and reboot the system


   IV. Installing multiple PCI boards
   -----------------------------------

      Repeat the procedure described in the previous paragraph.

