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          Beta V0.25
          ----------

          Corrected  problem introduced  in  0.25 where  many OS2  programs
          could not drop DTR.

          Beta V0.26
          ----------

          If a set DCB  IOCTL is issued, and if pending reads/writes exist,
          the suspended threads are restarted.

          Previous versions always placed port  addresses in BIOS memory at
          40:0 (DOS sessions) for  both COM1 and COM2.   The port addresses
          starting at 40:0 are no longer filled in for COM1 and COM2 if SIO
          did not detect a port there or if the mouse is using the port.

          I believe the problem of DOS sessions being put to sleep has been
          solved.  V0.30 works well on my system with default DOS  settings
          and default CONFIG.SYS entries as follows:

               In the DOS settings
               IDLE_SECONDS = 0
               IDLE_SENSITIVITY = 75

               In CONFIG.SYS
               MAXWAIT=3
               PRIORITY_DISK_IO=YES

          Note that I  said these default settings work  well with V0.30 ON
          MY SYSTEM.   The above  settings may have  to be changed  on your
          system.

          Beta V0.30
          ----------

          An error has  been corrected in the code for DOS sessions dealing
          with the comm port addresses at 40:0.

          Beta V0.31
          ----------







          Beta V0.31
          ----------

          Bit 6  of the virtual  Line Status  Register (LSR) was  stuck on.
          This  has been corrected and it probably caused some DOS programs
          problems.

          After two days  of testing  why incorrect "COMn  already in  use"
          errors  were occurring in DOS  sessions, I traced  the problem to
          the Novell Lan Drivers that I am using.  It seems that the Novell
          OS2 requester drivers are  using memory that is not  allocated to
          them.  I have  worked around this problem successfully  by making
          the Novell drivers the last thing in CONFIG.SYS.

          Corrected a problem in the handling of DSR.

          Corrected a problem  that caused erroneous "COMn  already in use"
          in OS2 sessions.

          Added OSDR and IDSR modes or operation.

          If  SIO/VSIO  seems  not  to transmit  anything,  where  previous
          versions  transmitted okay, then set  your modem to  force DSR ON
          or, set ODSR OFF with the MODE command.

          If  SIO/VSIO  seems  not  to  receive  anything,  where  previous
          versions received okay, then set  your modem to force DSR ON  or,
          set IDSR OFF using the MODE command.

          Support added for forcing 16550A chip type. (COM1,3F8,IRQ4,,F)

          Corrected a serious problem with multiple comm ports  sharing the
          same IRQ.

          Beta V0.34
          ----------

          Corrected a  problem in the  Virtual Line Status  Register (LSR).
          This problem showed up in DOS sessions as a very slow transmit at
          speeds below 9600 baud.

          Corrected a problem in the Virtual Interrupt Enable register.

          Corrected  errors in  the  implementation of  DTR  enable/disable
          mode.

          Corrected and error that may have caused problems at shutdown.

          An  apparent OS2  problem  of "LOCKED"  memory erroneously  being
          moved  has been worked around.   This could  cause many problems.
          Most often,  erroneous "port  already in use  messages" and  just
          plain crashes.

          Beta V0.40








          Beta V0.40
          ----------

          Corrected a problem of crosstalk from COM3 to COM2.

          Changed  the method  of memory  allocation.  On  my system,  I no
          longer have to load SIO.SYS after the Novell drivers.

          Corrected  a  problem in  cleanup  when an  open of  a  comm port
          failed.   This  problem showed  up as  a dead  port once  a "port
          already in use" was issued.  The correction of this error  should
          allow SIO and PMfax to get along better.

          Beta V0.43
          ----------

          Corrected  a problem in  Device Close  operations.   This problem
          prevented serial  printers, and  modem commands from  batch files
          from working.  This problem could show itself in many other ways.

          Additional  corrections to clean up after a "port already in use"
          occurs.  Again, SIO and PMfax should get along better.

          Added PROBLEM.TXT to the distribution file.

          Beta V0.45
          ----------
