                   Release Notes  PN 93000160

                      Digi RealPort Service
                  Version 2.8.94.2, 11/04/2004

                    Microsoft Windows NT 4.0
                    Service Pack 5 or better

                  Software Package PN 40001738


  CONTENTS

  Section      Description
  -------------------------------
  1            Introduction
  2            Supported Operating Systems
  3            Supported Products
  4            Known Limitations
  5            Upgrading RealPort
  6            Additional Notes
  7            History

  1. INTRODUCTION

     This document describes the service that supports the
     Digi devices listed below.  The service is for use
     with Microsoft Windows NT 4.0.

     Refer to the following number when searching the Digi
     International Inc. Web site (www.digi.com) or the FTP
     site (ftp.digi.com) for the latest software package:

     40001738_<highest revision letter>

  2. SUPPORTED OPERATING SYSTEMS

     Microsoft Windows NT 4.0, Service Pack 5 or better

  3. SUPPORTED PRODUCTS

     Digi Connect Family
     Digi EtherLite Family
     Digi Flex Family
     Digi One Family
     Digi PortServer Family
     Digi PortServer TS Family
     Digi PortServer TS MEI Family
     Digi PortServer TS W MEI Family
     Digi PortServer TS M MEI Family
     Digi PortServer TS H MEI Family
     Digi PortServer TS P MEI Family

  4. KNOWN LIMITATIONS

     Changing the baud rate of a serial printer requires deleting
     the printer device and then re-adding the device with a
     different baud rate. This is a Print Manager limitation in
     Windows NT 4.0.

     If you plan to use the RealPort service with serial
     printers, you have to reboot the system after device
     installation or after renaming ports to see the new ports
     listed in the Print Spooler's list of available ports for
     printing. This is a known limitation of the Print Spooler,
     which does not detect changes in the list of available ports
     automatically.

     If you experience problems printing to a serial printer,
     navigate to the device's Device Properties dialog in the
     Device Manager, enable "Complete Write Requests Immediately,"
     and try printing again.

  5. UPGRADING REALPORT

     UPGRADING FROM AN ETHERLITE DRIVER
     ----------------------------------

     If you have previously installed the EtherLite driver for an
     EtherLite device (EtherLite 2/8/16/32/80/160/162), follow these
     steps to upgrade to the current RealPort service:

     a. Uninstall the old EtherLite driver and reboot the system.

     b. Update the EtherLite firmware using the DGIPSERV utility,
        which is included in the driver package. You can download
        the latest firmware files from the Digi Support Web site,
        http://support.digi.com.

     c. Install the new RealPort Service.

     UPGRADING AN EXISTING REALPORT SERVICE
     --------------------------------------

     To upgrade a previously-installed RealPort service to the new
     service, follow these steps. Note that the "Update" feature
     available from the Services Tab of Network Neighborhood Properties
     is not supported -- instead, you must first uninstall the existing
     RealPort service and then install the new RealPort service:

     a. First, navigate to the Services Tab:

          o From the Desktop, right-click "Network Neighborhood"
          o Select "Properties"
          o Click on the tab marked "Services"

     b. Next, uninstall the existing RealPort service:

          o Select "Digi RealPort Service"
          o Click "Remove"
          o Click "Yes"
          o Click "Close" to dismiss the Network window
          o Click "Yes" to restart Windows

     c. Finally, install the new RealPort service:

          o Navigate to the Services Tab (see a. above)
          o Click "Add"
          o Click "Have Disk..."
          o Enter the path to the new RealPort service files
          o Click "OK"
          o Click "OK"

     d. Follow any other instructions to complete the installation.

  6. ADDITIONAL NOTES

     On-line help is available when you install the product.

     Installation documentation can be found at Digi's Web site,
     http://www.digi.com, or at Digi's FTP server,
     ftp://ftp.digi.com.

     ADVANCED DEVICE SETTINGS
     ------------------------

     The RealPort driver supports an additional set of advanced
     features, each of which can be enabled or disabled from the
     Device Manager:

         o Right-click "My Computer"
         o Select "Manage"
         o In the left-hand side of the Computer Management
           window, select "Device Manager"
         o In the right-hand side of the window, expand the
           "Multi-port serial adapters" category
         o Right-click on the device to configure
         o Choose "Properties"
         o Navigate to the "Advanced" tab
         o Verify that the top-level device (the RealPort
           device) is highlighted and select "Properties..."
         o The Advanced Properties dialog is displayed, which you
           can use to enable and disable the advanced features.

     Each of the advanced features discussed here is disabled by
     default.

     COMPLETE WRITE REQUESTS IMMEDIATELY
     -----------------------------------

     Checking this field means that the driver confirms the
     completion of a write request as soon as data is written to
     the buffer. The default is to wait until the data is sent
     out the port.

     SEND KEEP-ALIVE PACKETS
     -----------------------

     Sending keep-alive packets is a mechanism for keeping a TCP
     connection up all the time, even when there is no network
     traffic between the RealPort driver and the Digi device.

     ALLOW PORTS TO BE OPENED WHEN NETWORK IS UNAVAILABLE
     ----------------------------------------------------

     Turn this feature on if you want the RealPort driver to
     always succeed open requests, even if the driver cannot
     communicate with the remote device at the time of the open.
     By default, the driver only succeeds an open request if it
     can communicate with the remote device.

     RETURN ERROR CODES WHEN NETWORK IS UNAVAILABLE
     ----------------------------------------------

     The RealPort driver supports two methods to handle Wide Area
     Network (WAN) errors, such as those generated when the
     RealPort driver loses its TCP/IP session with the remote
     RealPort device.

     By default, the feature is disabled and the RealPort driver
     seamlessly and transparently handles any and all network
     errors. The most common network error is that the driver
     loses its TCP/IP session with the remote RealPort device,
     either because the RealPort device is unreachable due to
     general network failures or because the RealPort device was
     rebooted or powered off.

     In the event that the RealPort driver loses its TCP/IP
     session with the remote RealPort device, the driver will
     attempt to reestablish a new connection with the device once
     every second. The driver will also simulate a loss of
     hardware flow control lines by lowering each of the following
     signals -- DCD, DSR, and CTS. It will also simulate receipt
     of an Xoff character, if software flow control is being used.

     In this mode, client applications will not and cannot detect
     network errors. Client applications are free to continue
     reading from and writing to any RealPort ports, and to
     continue using the ports as they otherwise normally would.
     In this way, network errors are handled transparently from
     the client application.

     However, it is sometimes useful for a client to know when the
     remote RealPort device is unreachable because the TCP/IP
     session was dropped. In this case, you can check the "Return
     error codes when network is unavailable" feature, and the
     RealPort driver will then communicate network errors to the
     client when the network is unreachable.

     In this mode, if the network connection is dropped and a
     client initiates a read or a write, the driver will
     immediately complete the operation and return the error,
     ERROR_NETWORK_UNREACHABLE. A client application can be
     modified to recognize this error code and to respond to the
     error by performing some special operation, such as logging
     the error to a file. The driver will continue to return this
     error code until it is able to reestablish a network
     connection with the remote RealPort device, at which point
     the driver will resume normal processing of reading and
     writing to the port.

  7. HISTORY

     Version 2.8.94.2 (Rev. N2, November 04, 2004)
     ---------------------------------------------
     o Added support for Digi PortServer TS MEI Families, including
       Wireless, Modem, Hardened, and Power series.

     Version 2.8.94.1 (Rev. N1, April 09, 2004)
     ------------------------------------------
     o Added support for Digi Connect SP, Digi Connect Wi-EM, 
       Digi Connect Wi-ME, and PortServer TS 8/16 MEI.

     Version 2.8.94.0 (Rev. N, June 10, 2003)
     ----------------------------------------
     o Added support for Digi Connect ME.
     o Fixed a problem processing write requests after the input
       buffer is cleared with PurgeComm during network disconnect.
     o Corrected break event signaling.
     o Fixed detection of modem line transitions for EtherLite 2.

     Version 2.7.90.0 (Rev. M, April 22, 2003)
     -----------------------------------------
     o Improved management of outgoing network resources.
     o Fixed a condition where a network disconnect under certain
       conditions may cause a bugcheck.
     o Fixed RTS Toggle functionality. A RTS pre- and post-delay
       can be configured through the command line interface or the
       web interface of your Digi One or Digi PortServer.
     o Modified the Complete Writes Immediately feature to allow
       queued data to drain when the port is closed.
     o Fixed framing error detection to not insert bogus data
       into the read data stream.
     o Modified driver to default uninitialized ports to 1200,7,e,1,
       like the standard serial driver, and to maintain baud rate,
       line settings and flow control across opens.
     o Added code to force RTS low when device is closed; sometimes,
       if a port was using RTS/CTS flow control and was closed, RTS
       would remain high.
     o Added support for Digi One TS H, Digi PortServer TS 2 H,
       and Digi PortServer TS 4 H.
     o Added support for Digi One TS W, Digi PortServer TS 2 W,
       and Digi PortServer TS 4 W.

     Version 2.6.82.0 (Rev. L, January 31, 2003)
     -------------------------------------------
     o Added support for Digi One EM, Digi One IA and Digi One SP.
     o Fixed race condition when switching parity states.
     o Modified Complete Write Requests Immediately feature to work
       irregardless of flow control.
     o Added user interface option "Send keep alive packets" to control
       keep alive packets sent to the remote device. The default setting
       is disabled.
     o Fixed condition where default Xon and Xoff characters were
       not initialized correctly.
     o Fixed detection of parity and framing errors.
     o Fixed Xon/Xoff limit bounds checking.
     o Exposed GUI option to allow serial ports to be opened
       even if the driver cannot communicate with the remote device.
     o Improved driver load time when network is disconnected.
     o Changed event reporting to begin accumulating events once
       SetCommMask is called, instead of waiting for WaitCommMask.

     Version 2.5.67.0 (Rev. J1, August 07, 2002)
     -------------------------------------------
     o Enhanced network interface to more efficiently process
       data when presented with out-of-sequence and fragmented packets.
     o Fixed completion of writes for ports not using flow control
       but enabling DTR or RTS.
     o Improved detection and reporting of local network disconnects.
     o IRP_MJ_READ was not completed although a non-zero value for
       the ReadIntervalTimeout was set.
     o Latency enhancements.
     o Enhanced logging of error conditions in System Event Log.
     o Added user interface option, "Complete write requests
       immediately," for timing-sensitive applications.
