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                      VARIAN ASYNC32 COMPONENT 
               (c) VARIAN SOFTWARE SERVICES NL 1996-1998
                           ALL RIGHTS RESERVED
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*** Version 1.49

- Release for Delphi 4

HISTORY

** Version 1.26

- First, our special thanks goes to:

  Laco Laszlo
  Czech Republic
  E-mail: lacola@usa.net

  David J Rose
  Senior Software Engineer
  NexSys
  E-mail: DavidRose@nexsys.demon.co.uk

  and all the others who contributed their suggestions...


- implementation of Exceptions and Handling

- Removed OnOpenEvent, Error parameter replaced by exceptions.
  ProviderSubtype parameter replaced by public property

- Fixed write statement bug by setting the WriteCommTimeouts <> 0

- Write statement now reports the correct number of bytes send

- The read and write statements now report an errorcode -1 when IO is pending
  instead of returning zero bytecount. This gives the application the
  opportunity to simply resend or cancel the operation.

- Moved the XonChar and XOffChar to a new class object "TCommEventChars"

- Changed properties WriteBufferSize, ReadBufferSize in WriteBufSize, ReadBufSize.

- Removed all numeric "32" references, TComm32 is now called TComm.  

- Changed CommEscapeFunctions DTR, RTS, BREAK, XON functions in procedures   
  procedure SetDTRState(State: Boolean);
  procedure SetRTSState(State: Boolean);
  procedure SetBREAKState(State: Boolean);
  procedure SetXONState(State: Boolean);

- Added help documentation regarding properties, methods and events.

- Some internal syntaxis rewrites



* VERSION 1.01

- The Thread is now created in a "suspended" state and is
  resumed after initialization of all variables.
  By Gary Weinfurther <gary@mich.com>

- Added additional code to Escapecomm function <BREAK> to ensure
  correct dataflow.

- Rewritten the "write" procedure. It should work fine now.

- Updated the demo program to test XON/XOFF flags.


* VERSION 1.0

-Changed the receive part for the demo application.

-added device indentification to OpenEvent, see provider subtypes for
 more info.

-added device DCB profile to open procedure

-added additional port-settings through "Options" property

-added missing escapecomm function "xon/xoff"

-the component waited (infinite) for write operations to be completed after
 XOff or Break. Fixed.
 The function now returns zero bytes written on an IOPending event.
 Initial idea by Piet Jansen <pietjans@tref.nl>

-Removed "signal" extensions from event properties.
 sorry for the inconvenience this may cause.

-Moved Event calls to dynamic procedures in order to enhance inheritance.
 Initial idea by Tim Evans <vgs.mil@interbusiness.it>

-Removed some Delphi VCL units from the uses clause.

-Added handshake handling
 by Gyula Mészáros (Mr. InnMaxX), Hungary
 e-mail: 100263.1465@compuserve.com



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