         _____ _                   _____  _____          _____          
        / ____(_)_            _   / ____|/ ____|   /\   |  __ \   /\    
       | |     _| |_ ___  ___| |_| (___ | |       /  \  | |  | | /  \   
       | |    | | __/ _ \/ __| __|\___ \| |      / /\ \ | |  | |/ /\ \  
       | |____| | ||  __/ (__| |_ ____) | |____ / ____ \| |__| / ____ \ 
        \_____|_|\__\___|\___|\__|_____/ \_____/_/    \_\_____/_/    \_\
 
                           CitectSCADA Driver Pack                             


>>>NOTE

The PSDIRECT Driver is the frontend half of a frontend backend pair this revision history refers to changes to the FRONTEND
PSDIRECT.DLL   

PSDIRECT.DLL converts Citect IO requests into Data Calls to the backend, this means the primary function is 
data conversion & emmulation.

All issues relating to communication are backend issues.

Extra functionality has been included to make sure the #COM & Server failover function correctly
 seeing that the data is derived from a memmory cache
 
 
PSDIRECT driver v2.5.3.200
===========================
Date:      03/03/2011

Change:    - Fixed OS version to run on Win & & 2008SR2
		   
 
PSDIRECT driver v2.5.3.000
===========================
Date:      27/08/2010

Change:    - Bug fixes on Aritec Protocol
		   - Improved startup & shut down - possible issues
		   - Added ability to read status tags without geting #COMM errors
		   - Added S5 Serial

PSDIRECT driver v2.5.0.000
===========================
Date:      22/06/2008

Change:    - Added Aritech protocol


PSDIRECT driver v2.4.3.000
===========================
Date:      22/03/2007

Change:    - Migrated some changes relating to Unitstatus from S7 protocol to others, in particular less sensitivity to multiple channels

PSDIRECT driver v2.4.2.000
===========================
Date:      18/03/2007

Change:    -Improved error handling of incorrect UnitTypes - normally from clients running S7NT or TINECNT
	   -Removed Compiler ASSERT()

PSDIRECT driver v2.4.1.000
===========================
Date:      01/02/2007

Change:    -Added TI WY datatype
	 

PSDIRECT driver v2.4.00.000
===========================
Date:      12/12/2006
Bug Fixes: Fixed problem with S7 Strings of length 255
	   Fixed problem with S5 strings longer than 126

New:	   Support for Siemens TI PLC debugged & improved
Change:    Support for Square D Driver

PSDIRECT driver v2.3.00.005
===========================
Date:      09/06/2006
Change:    Compiled with MSVC6 & removed MSVCR8 dependancy


PSDIRECT driver v2.3.00.004
===========================
Date:      25/05/2006
Bug:       Fixed issue relating to using _32 as 2nd IO device name

New features:

-	Increased number of IO devices to 128
-	Increased blocksize to CiTect max of 2048 bits, only useful for those using big arrays
-	Now allow multiple channels, but still recommend only one
-	New Status register addresses to monitor backend redundant address status
-	Now allow multiple Citect IO devices connecting to one backend IO Device
-	Substantial work on the IEC 870 protocol



PSDIRECT driver v2.2
=========================
Date:      10/12/2005
Bug:       Kelvin proctor reported a GPF associated with the Format() function, so several changes were made to 
	   all string manipulation routines to avoid buffer overruns.  all sprintf() functions replaced with snprintf()
           all strcpy() with strncpy() etc.  Note the GPF was never observed during testing.



PSDIRECT driver v2.1
=========================
Date:      13/10/2005
Bug:  	   Fixed problem with S5 LONGS
	   Fixed S7 I PI & PE addresses

Comment:   S5 Long problem was a resolution problem due to truncation when the LONGS were converted LONG-32bitFloat-LONG in the backend
	   The I,PI, & PE data types were incorrectly converted
	   




