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                    RELEASE NOTES FOR MODSOFT REV. 2.51
        
       If you have problems using this software, call your local 
       distributor.
     

       The second disk set labelled "Loadable/Execs" contains Compact 
       Drivers, Compact Executives, Quantum Drivers, Quantum DX loadables
       and Quantum Executives. This file set is not compressed.  You simply 
       copy files you need to where you know you can access them by Modsoft.

       TO ALL BETA TESTERS, RE MICRO 612-4 MEMORY MODEL CHANGE:
       THE MICRO 612-04 CHANGED THE MEMORY MODEL SIZE FROM 8K TO 9.1K DURING 
       THE BETA CYCLE.  IF YOU HAVE OLD 612-04 PROGRAMS, THEY WILL NOT HANDLE 
       TO FULL 9.1K SYSTEM MEMORY AS IS.  THE CONTROLLER WILL ALLOW 9.1K BUT 
       MODSOFT WILL NOT ALLOW YOU TO DOWNLOAD OVER 8K.  TO REMEDY THIS YOU 
       MUST OPEN THE PROGRAM OFFLINE AND CHANGE PLC TYPE MOMENTARILY TO 
       612-03 AND BACK TO 612-04.  NOW MODSOFT WILL ALLOW FULL USE OF THE 
       9.1K FOR LADDER LOGIC AND CONFIGURATION.

       TCP/IP installation requires that you edit the file VSLDOS.INI located
       in "modsoft\vsl" directory.  Find the line that starts as 
       TRANSPORT=<netkey>; where "netkey" is the name of the TCP/IP stack.  
       Replace "<netkey>", with the name of the TCP/IP stack that is 
       appropriate for your installed Ethernet card.  In the case of 
       Win '95, the line would look like this:

                             TRANSPORT=winsock

       Please refer to the "readme.txt" file located in the "modsoft\vsl"
       directory. This file contains further detailed information and a list 
       of supported TCP/IP stacks.
      

       Note 1: Modsoft can no longer be supported on XT and AT systems. 
       CPU 286 systems without at least 4 MB total RAM will not be 
       supported as well. (It is not recommended that Modsoft be run on a
       286 machine as faster machines will provide more satisfactory results.)

       Note 2: Do not use Doublespace in the TMP directory of Modsoft without
       disk caching or Modsoft performance will be slower than normal.

       Note 3: Modsoft 1.1->Modsoft 2.51 requires that the MAP 3.0 
       communications can only be used with version 2.3 or greater of 
       the ISOcomm software.
       
       Note 4: The Configuration Extension, S980 Address, is not utilized
       by all versions of the S980. If the S980 User's manual does not have
       information about the S980 personality mismatch detection, do not 
       use this feature.
        
       Note 5: The 984-685E, 785L, 785E, Quantum, and Momentum controllers 
       must use DX Loadables with a revision level of 192 or greater. 
       
       Note 6: The Modsoft Print Utility attempts to open and use three 
       different font styles: (1) The network graphics are selected to be 
       constant pitch; (2) The comments and symbols are in a scaleable font 
       for information to be placed above a node; (3) The text for the 
       configuration information is fixed pitch for tabular alignment, 
       but smaller type size (minimum 8 points).
       
       Most older printers will not support all three type faces. 
       
       Selecting the minimum font size will have different effects on the 
       three potential fonts.  1) there is no effect on the fixed pitch 
       graphics font.  2) The general text font may not have the ability to 
       be set to the exact font size requested, and may end up smaller.  
       3) The comments and symbols font may be scaleable and show up as the 
       only thing that appears to be obeying the minimum font size rule.
          
       It is advisable to try an experimental printout of a single network
       to see the effects of your font size selection.  

       If you do not set a minimum font size in the UPF editor, the 
       minimum font size is implied to be 6 points, and is guaranteed to 
       apply only to the scaleable font used for comments and symbols in the 
       network listing.

       Note 7: Not all the 4X registers are being marked in the Used
       Reference Table. This is due to functions, such as XMRD and XMWT
       which use indirect addressing for the destination of data. Due to the
       fact that the values in these pointers can change control of the
       application, there is no way any programming package would be able
       to automatically build a 4X used table that would include these 
       registers.

       The recommended work around is to use other functions such as BLKM
       in the logic so that the 4X registers will be found as used and placed
       in the Ref Used Table. These functions can be placed either in the
       same network as the functions that are indirectly using them, so that
       the cross reference can generate the correct network for the
       reference usage. Or, if scan time is an issue, the BLKM functions
       can be placed in a segment that is not being used and has been
       removed from the segment scheduler so they will not be scanned.

       Note 8:
       RTU protocol: This protocol was designed for optimal speed and as a
       result has very strict timing restrictions. The protocol requires
       that a message be transmitted with less than a 3.5 character time
       gap between each character transmitted. A gap in excess of the
       3.5 characters is seen as the end of the message. On dedicated
       machines such as a PLC, this is not a problem, but on a multipurpose
       machines such as a PC, this is difficult. Interrupts from the
       system clock, a Modbus Plus card, the keyboard, or a network card
       can all take the CPU several milliseconds. This can delay the
       transmission of characters when the baud rate is 9600 baud beyond
       the 3.5 character limit, thus terminating the message. The PLC
       sees this message as being incomplete and ignores the message.
       Modsoft must then time-out and try again.

       The problem is more severe on systems such as Windows, Windows 95,
       and Windows NT, where there are other tasks executing at the 
       same time. This can cause delays that render RTU mode unreliable.

       There is no one solution to the above problem. The following three
       suggestions are given as possible workarounds.

       a) If RTU is a problem on a system with network cards, remove the 
          drivers when running RTU. In older versions of Modsoft, the
          Modbus Plus driver was turned off when RTU was to be used,
          however, customers that were using Modbus Plus for another
          application simultaneously could not run. Since Modsoft no longer
          turns the Modbus Plus driver off, the user must turn off the
          driver manually.

       b) Another suggestion involves the use of PC systems with 16550
          UARTs. These systems have a transmission queue of 16 characters,
          so the PC has the transmission time for 16 characters to do other
          things before a message in incorrectly terminated. A faster CPU
          also lessens the impact by processing other tasks more quickly.

       c) The final suggestion involves avoiding use of RTU mode on systems
          where it is a problem. The ASCII protocol will handle RS-232
          communications with the PLC with a little degradation in performance.
          Modbus Plus is also an option where the PLC can handle the protocol.

       Note 9: On PCs which utilize Network software; there exists the 
       possibility that the Modsoft Install and Update disks may not be able 
       to install/update. If this happens, please disable the Network TSRs, 
       reboot the PC to release memory resources and attempt re-install of 
       Modsoft.

       NOTE 10: Installing or Updating Modsoft may require you to register
       your name and company name. The use of the apostrophe in the Your Name
       and Company Name fields will corrupt the fields such that when
       Modsoft is invoked the user will be placed in Trial Modsoft. DO NOT
       USE APOSTROPHES in these fields. If this happens call your Customer 
       Support for a new "text2.sys" file and re-install the software as 
       instructed.

       NOTE 11: There are situations where Modsoft communications could be
       unreliable due to limitation of the capabilities of the hardware.
       If the user has a slower PC and was trying to use Modsoft at 19200
       baud under Windows, the failure appears to be a receive overrun. 
       This means that the 984 PLC sent characters to the PC faster than the
       PC software could process them. With Windows running, Windows itself
       and other operating software can be taking CPU time away from Modsoft.
       At 19200, the CPU only needs to be away from Modsoft for 2-3 ms for
       an overrun to occur.

       There are several solutions that should be looked at. First, the mix
       of executing Windows applications should be examined, and the priorities
       set so that Modsoft has enough time to run. A slower baud rate will 
       also help. Running on a faster PC is another solution. A final solution
       is to use a PC with 16550 UART. This UART was designed to help Windows 
       with this situation by increasing the hardware receive buffer from 3 
       to 16 characters (increasing the time before an overrun occurs from 2
       milliseconds to 8 milliseconds at 19200 baud).

       NOTE 12: The new Quantum controllers have additional function built-in
       function blocks. This may cause collisions with loadable functions
       using the opcodes now assigned to builtin functions. If this happens,
       go to Offline->Config->Loadables and change the opcodes to unused ones.
 
       NOTE 13: Sy/Max implementation in Quantum is controlled by the UPF editor.
       Selecting "Yes" to the Sy/Max S908 IO Drops field grants the user permission
       to configure Sy/Max S908 Drops and Sy/Max Ethernet Config Extension.
       Turning off ("NO") the Sy/Max flag does not cause the programmer to lose
       the Sy/Max drops or the Ethernet Config Ext if already created.

       NOTE 14: When using Modsoft Lite and setting the Modsoft driver via the UPF 
       editor, please be certain that the file created is named 'lmodsoft.upf'.
       If not, the editor assumes 'modsoft.upf' and Modsoft Lite will ignore this
       name and the MB+ setting. 

       NOTES ON MODSOFT 2.4 VERSION:

       NOTE 15: Via TCP/IP, it is not possible to get the hardware ID., the
       executive ID., or the executive rev. on a per slot basis through
       the Quantum Backplane. The only per slot information that is displayed
       is personality and module description.

       NOTE 16: If you see this message "TCP/IP can not assign requested 
       format" ensure that a TCP directory exists. The TCP directory should 
       contain a SERVICES, PROTOCOL, HOST and RESOLV.CFG file.  See the 
       READ.ME in the \modsoft\vsl directory for further information on the 
       contents and placement of the TCP directory.

       NOTE 17: If you see this message "Timeout without a PLC response" using
       TCP/IP, check the communications_timeout in the UPF and increase it, if
       necessary.  A value of 30 seconds should generally suffice for TCP/IP.

       NOTE 17: If you see this message "The selected Communications Mode is
       not available when using TCP/IP, ensure that you can "ping" the node
       in question.  Ensure that the TCP/IP and the Network Module drivers
       are loaded. Ensure that the VSLDOS.INI file correctly reflects the 
       Network Module (netmod) corresponding to your TCP/IP stack.  See the
       READ.ME file in \modsoft\vsl directory for further information on
       loading the communications drivers and configuring the VSLDOS.INI
       file.

       NOTE 18: TCP/IP communications reports Rtcp (Running controller via
       TCP) or Stcp (Stoppped controller via TCP) in upper right corner of 
       the screen while online to a controller.  Usually this field 
       reports the status of the controller as well as the slave address. For 
       TCP/IP, the slave address does not exist.

       NOTE 19:Users unfamiliar with the TCP/IP protocol may not realize
       what constitutes a broadcast address. See Documentation for NOE 211
       module.

       If the user enters an IP address that is a broadcast address, or enters an IP
       address that is illegal, the cursor will be placed at the beginning of the
       IP address field and Modsoft will wait for a correct address to be entered.

       NOTE 20:Loadables that have an extension of .exe produce different library
       files for 16 bit controllers( e.g. Quantum 186, Compact, Micro, 984 slot
       mount controllers) and 32 bit controllers (Quantum 424, VME 424). The loadable 
       files are only common in the original distributed file (relocatable
       format). Due to this, it is not possible to load and run library loadable
       file for the 186 on a 486 controller and vice versa.  It is therefore 
       STRONGLY recommended that you segregate your project programs for 32 bit
       controllers from all other 16 bit project files.

       NOTE 21:Projects List: If there are over 116 project names in your 
       projects subdirectory, the screen cannot show them all at the same time. 
       A border for the projects selection list will contain  --<<----- project 
       ----->>-- to indicate that more names in the list by pressing either 
       the right arrow cursor key or the left arrow cursor key.
       
       The maximum number of projects that can be shown in this expanded 
       window is 252.
       
       It is recommended that you do not have so many projects in a single 
       projects directory. A grouping of your projects by geographical or 
       functional categories is recommended to keep the number well below 
       116 in a sub-directory.
       
       NOTE 22: Config size adjustments from prior releases:
       Modsoft 2.4 corrects several places that the config size was incorrect 
       in the past.  You may find that attempts to go on-line in combo mode 
       from Modsoft 2.4 without first transferring the program to the PLC 
       from Modsoft 2.4 can prevent access to the configuration section. If 
       this happens, transfer the project to the PLC later at a convenient 
       time.
       
       NOTE 23: Printer databases compatibility:
       It may be possible that your new printers.pdb contains changes, from 
       the previous release. Such changes are not automatically reflected in 
       YOUR Modsoft.pdb. This will not affect your current printing with 
       Modsoft.pdb.  However, if you edit your printer preferences using the 
       UPF editor, you may encounter compatibility issues between the 
       databases.   If this happens,  and you need to change the definitions 
       or your device, you will have to re-define the printing device that 
       has the conflict, after removing it from the Modsoft.pdb database.
       
       NOTE 24: .EXE Loadables Library files:
       When a project is transferred from the controller to a set of files, 
       any .EXE loadables that are transferred are saved within the project 
       files for subsequent downloading.  These transferred loadables are 
       in absolute addressing format, and are now applicable only to the 
       project and to the PLC type.  Any attempt to change PLC type on 
       the program will potentially make the loadable un-usable.  If this 
       happens, it will be necessary to delete the project's *.usl file in 
       your programs directory and configure the loadable once again. 
       
       NOTE 25: LIBRARY operations:
       When copying and pasting from Library prg files, it is wise not 
       to do too many networks at a time.  As in many other editing operations 
       in your PC, it is recommended that you exit and/or save the changes 
       made frequently.  It is recommended that you limit your repeat 
       operations of entering the library to five or six, before exiting the 
       ladder editor and saving the changed files.
       
       NOTE 26: Correct PC date is important;
       Modsoft will prevent you from using a PC date prior to 1994. This 
       can happen accidentally if your PC's clock battery needs replacing. 
       
       NOTE 27: Pasting networks with comments:
       Pasting Networks can take a long time to perform if a large number of 
       networks are selected at the same time.  Times of over 10 minutes have 
       been experienced.  

       Recommendation:  Do ten or so at a time, and then exit the editor, and 
       then save the program.

       NOTE 28: When updating Modsoft, the "modsoft.pdb" file is not updated.
       This is to preserve your current printer preferences. The "printers.pdb"
       may be optioned to be updated. In some cases, the printers.pdb database
       may have been changed and one or more of your printer types in
       modsoft.pdb may not match the main database.  If you attempt to edit
       your Modsoft printer preference, you will see errors messages. You
       should then delete the outdated printer from your list and re-enter
       it using the UPF editor.  This should be an infrequent occurrence.


       MODSOFT 2.51 Notes

       NOTE 29: Momentum M1, IObus screen header has some variations from 
       the usual Quantum IOMap screen.
  
       a) Header Does not count input and output points in two separate fields.
    What is counted and displayed is the number of used IO Points in
    the Interbus-s style network of modules.   This number is not the
    simple sum of the inputs and outputs.  It is rather the sum of the
    individual modules' io width.  The IBSS module width is derived
    from the larger of its input and output points.  
       b) The left counting columns on module lines is the page and node numbers.
          The node numbers are per page, and range from 1 to 16, per page.
       c) Modules may not be placed in node positions such that there would be
          any empty node positions.

       NOTE 30: Write protection of project files will cause problems in downloading 
       if the .map and/or .cut project files are protected.  Modsoft must write 
       to these files in the process of downloading.  You will see a message 
       about the file being opened followed by a message about the DOS 
       environment error that ensued.

       NOTE 31: It has been noted that some users of compact plcs and modules have 
       attempted to use the bidirectional 8 bit DAP 212 and share the output 
       state word with the 8 bit output module DAP 208.  Modsoft does not prevent 
       this otherwise illegal operation.  The PLC will not start, giving a 4000 
       error. Bi directional 8 bit modules must share state words with other bi
       directional 8 bit modules.  They cannot be mixed with single input or
       output 8 bit modules.

       NOTE 32: VERY IMPORTANT NOTE:
       =============================
       Controllers which have battery backup and/or  erasable prom (or flash) 
       storage of programs are recommended to be de-commissioned or re-commissioned 
       in a well organized process.  The issue is that it is possible for a PLC 
       which has been in service to be put into spares in such a way that it will 
       immediately enter the RUN mode when power is re-applied. There is a potential 
       for the programming and configuration in the PLC to be such that some 
       attached IO may be inadvertently activated.  Particular attention to this 
       is advised when PLC(s) are swapped in a trouble shooting process, and then 
       returned to spares.  If you properly de-commission a PLC, it is useful
       to tag it as OK to re-commission as is.  This can save time.

       De-commissioning: 

       * Care should be taken to shut down a controller before removing it 
         to spares. 

       * If the controller has a battery, it is advisable to remove it and 
         tape it to the side for future use.

       * If the controller has EEPROM or FLASH or Equivalent storage of the 
         configuration and program instructions;  it is strongly recommended 
         that the PLC be conditioned so as to insure that it will not 
         automatically RUN when power is applied.    
         
         This may be accomplished most simply by performing a Save to EEPROM 
         (or Save to FLASH) operation on the controller with option selections 
         set such that the PLC will be stopped after power is re-applied.

       * Another approach is to download an empty program, without any IOMap 
         or executable program, and to Save to EEPROM  (or FLASH) before removing to the spares pool.

       * Tag the PLC as having been properly De-commissioned.

       Re-commissioning:

       * Arrange to apply power to the PLC in such a way that the IO 
         is not powered or connected to the PLC.  This will allow you to download 
         a program that is intended for the application at hand before applying  
         power to the IO and running the Program.

       * Field wiring should consider the need to power the PLC independently 
         of the IO.

       * Apply power to the PLC and STOP it before connecting any remote IO, 
         Distributed IO, Peer Copped connections. 
 
       * Apply power to the PLC and STOP it before connecting to any 
         Interbus-s, Profibus, Fieldbus etc. IO.  These may best be 
         disconnected at the IO heads in the local back-plane, or equivalent.

       Note 33: Sharing Violations
       a) If another application such as an editor or another instance of Modsoft
       is running in another DOS window has accessed one or more files in the
       TMP directory Modsoft will quit with a "sharing violation" error.

       b) Modsoft does not "lock" program files.  It is possible that two
       instances of Modsoft with different TMP directories can edit the same
       program files, with only the last edit saved changes being preserved.

       Note 34: 612-04
       The Micro 612-04 has double the size of execution buffer than Modsoft 
       assumes. This extra memory is for use with large loadables (*.usl). Modsoft
       accomodates this extra memory for loadables by assuming the ratio of
       page zero ladder logic to execution buffer is ten to one (instead of
       the usual five to one).  This grants space to the loadables but
       gives an incorret value of remaining page zero space for ladder logic.  
       It is possible to add ladder logic on-line that exceeds the off-line 
       calculation. Once uploaded it can not be downloaded to the plc.  This
       issue wil be corrected in Modsoft 2.6.

       Note 35: S908
       The S908 PLC with 1K drop size does not correctly identify as 1K
       drop size when connected online direct mode.  Modsoft will prevent
       adding over 512 Input&Output in the drops in this mode.

       Note 36: EXE lodables for Momentum
       Momentum cannot use exe loadables that are designed for the Earlier 984's.  All 
       previous exe loadables have been identified internally as family 7.  Momentum
       will only allow exe loadables identified as family 8.   The family is not possible
       to tell from the external view of the loadable.  Family 8 loadables should have
       unique names (first four chars).  Only use loadables that you know are prepared
       for the Momentum.   If you inadvertently load a family 7 loadable to the Momentum
       an "Illegal Configuration" message will be received at the end of the exe loadable
       download process.  The PLC will be in Dim Awareness.   The same effect will be seen
       if you download a family 8 Momentum loadable into a quantum or other Prior PLC.


       Note 37: Modsoft 2.51 version is created to support increased Register 
       space and improved automatic handling of analog module parmameters.
       The module parmeter zooms were improved and/or corrected to match 
       the Module specification sheets and user manuals.

       Note 38: Momentum M1 exec 1.03 and greater...
       The Momentum M1 256k model now allows up to 4096 mix of 3x and 4x 
       to be allocated (configured). The effect of this increase from 
       2048 has decreased the page zero size from 14K to 12K.

       The IOMap module parameters are automatically  copied from the IOMap 
       area to the first (and following) output reference that is mapped to 
       the module. This copy operation happens at the end of each scan just 
       prior to writing the Outputs to the modules.

  
       Note 39: Since the two M1's have different state ram sizes (3K,6K), 
       the small M1 cannot be downloaded to a larger M1.  The program can be 
       copied from the small to larger M1 by using the Offline editing 
       Library operations.  An alternative is to make a duplicate of the 
       project files and use offlineto change plc types.  The single base 
       module that was in the TCOP is possibly not the same in the new 
       project anyway.




       The following problems, discrepancies, and workarounds have been found 
       in MODSOFT 2.21->2.51:
       
       ***Problem 1***
       If you push to DOS and try to PRINT or invoke a new TSR, you may hang 
       DOS, if memory is low. 
       
       ***Problem 2***
       CTRL F7 will not function in the CfgExt, Segment, Loadable screens.

       ***Problem 3***
       If Modsoft crashes while you are editing ladder logic in the Macro
       editor, Modsoft /s will not restore the macro edited.

       ***Problem 4***
       The Micro 311/411 and the A120 controllers do not have a second 
       Modbus Port. However, a second port is displayed and can be edited. 
       If the second port is edited, it will be ignored.

       ***Problem 5***
       If you create a loadable with 3 character names, Modsoft will change 
       them to four characters. The fourth character is an underscore(_).

       ***Problem 6***
       If you are in the CfgExt screen, setting the Words Reserved to a 
       value above what the controller has for memory, causes the
       Size of Full Logic Area to set to zero. You will get an error 
       message "Specified registers/references do not fit in controller
       state RAM".

       ***Problem 7***
       The RDE plus (+) key does not work with the Range function.

       ***Problem 8***
       Search Previous/Next in Online/Combo mode will search relative to 
       the last search location. Offline Search Previous/Next searches
       relative to the current cursor position.

       ***Problem 9***
       Peer Copped references are not noted in the used reference table.

       ***Problem 10***
       Create a IO Map online and start the PLC while still in the IO Map
       editor. Type ALT-N to goto next drop, you will see the warning
       message "PLC in Optimize Mode". Modsoft is trying to write the drop 
       again to the PLC. This is only an error message and does not
       impair usage of Modsoft.

       ***Problem 11***
       If you use Reference Zoom on a register and change the value Offline,
       with the RDE and register on the screen; you will notice that the 
       register did not change value. PageUp or PageDown keys can be used
       to refresh the screen.

       ***Problem 12***
       When changing between 800 and 200 series I/O controllers, remember to
       change the number of drops/channels from 1 to an even number. 200 
       Series I/O requires 2 channels per drop. If the channels are not even 
       numbered, upon controller startup, an error 0800 (Invalid Segment 
       Scheduler) will appear.

       ***Problem 13***
       When using the Offset feature in Netlist, both start and end 
       references must be of the same reference type (0X, 1X, 3X, or 4X).

       ***Problem 14***
       Due to the fact that the M984 iomap is organized inside the PLC
       differently from other 984's, the cross reference list building
       operation does not find references in the iomap of this plc.
       Network references are found and reported, however.

       ***Problem 15***
       On E785 Quantums, drop 1 is local. You can not use "GOTO drop 1".
       You will get an error message. The work around is to use the Previous 
       or Next Drop command to get to Drop 1.

       ***Problem 16***
       If you insert a three node function block over a one node or two
       node function block, you may see the new three node function block 
       one set of ????? missing in either the middle or bottom node. Type in
       the missing reference or constant value, to fix the problem.      

       ***Problem 17***
       Modsoft 2.21/2.3/2.4 allows configurations larger than 32K words. Most 
       controllers, except Quantum 424 and the VME-424, will disallow this.
       When an attempt is made to download a configuration greater that 32K
       an error message "Illegal Config" will be issued from the controller.
             
       ***Problem 18***
       Modsoft incorrectly write the constant sweep register numbers when 
       in Online/Combined modes. This only happens if registers above
       9999 are attempted to be used for constant sweep. Example: 419998-
       419999 becomes 409998-409999. The work around is to use only 
       registers below 9999 for constant sweep.

       ***Problem 19***
       More than 14243 words of IOMap area in 785E Quantum will cause an 
       "Illegal Config" at download.

       ***Problem 20***
       You can not use reserved system words for filenames, such as
       CON, PRT, PRINT, etc.

       ***Problem 21***
       If one or more *.tmp files are either write protected , locked or
       hidden in your \modsoft\tmp directory  Modsoft may incorrectly store 
       the <program/*.prg file after transfer from the PLC to File.  This 
       should be an unusual occurrence, requiring an outside influence or 
       intentional action within the operating system.  The only method to 
       correct this is to un-protect or free the file(s) and repeat the 
       transfer from the PLC to File.

       ***Problem 22***
       Conversion of files with macros to flat files may experience database
       errors. If this happens, it is necessary to temporarily rename the
       macro comments file names so they will not attempt to convert. After
       the conversion, the macro comment file names may be re-instated.

       Example:    Original Name              Temp rename
                  --------------------------------------------------
                    <macro>.mcr    ----->   <macro>.mcr  (no change)
                    <macro>.dbf    ----->   <macro>.fdb
                    <macro>.mcm    ----->   <macro>.mmc
                    <macro>.dbt    ----->   <macro>.tdb

                     Temp Name            Rename back to Original
      --------------------------------------------------
        <macro>.mcr    ----->   <macro>.mcr  (no change)
        <macro>.fdb    ----->   <macro>.dbf
        <macro>.mmc    ----->   <macro>.mcm
        <macro>.tdb    ----->   <macro>.dbt
       

       ***Problem 23***      
       Modsoft does not test the validity of nodes being pasted. In offline mode
       this is not a problem as the download process will test the nodes for
       validity. In online or combined mode, the controller tests the nodes
       and rejects illegal nodes.  Modsoft does not guard for this rejection
       in the paste operation and can result in a General Protection Fault. 
       This possibly can happen when copying and pasting from a library program
       since the library may have loadables that are not in the current PLC.

       
       ***Nuance 1***
       Pressing the Print Screen Key (or CTRL-P) may cause "Checksum Errors" 
       if the user is logged into the controller.
       
       ***Nuance 2***
       If an attempt is made to process a large group of references using 
       the Offset feature in the Symbol Table, expect the process to
       take a long period of time to finish. 
       
       ***Nuance 3***
       If you set your Location of Program Names to a drive other than C:,
       CTRL C out of Modsoft, then utilize Modsoft /s, the pathname
       will now default to c:\modsoft\programs. To prevent this from 
       happening, type the full pathname with the /s switch on the DOS 
       command line (i.e. modsoft /s d:\test).
  
       ***Nuance 4***
       To prevent splitting of networks across page boundaries you must
       limit the number of rows (lines) of comments and symbols that will 
       be printed. (This is very dependent on the capabilities of the printer.
       Use landscape mode wherever possible.) 
       
       To do this, use the UPF editor in the printer options, to
       set the maximum rows of comments and symbols. Generally limiting
       it to 2 rows of comments and 2 rows of symbols is adequate to keep
       7 nodes of network graphics on a page. Also invoke the single network
       per page parameter.

       ***Nuance 5***
       To get the best out of using laser printers: Since some of the older
       laser printers do not have so many fonts available, and the nicer
       IBM-2 character sets only come in one size, it is recommended that 
       you always use the laser printer in landscape mode when that mode is 
       available from the printer. This will also provide more efficient
       use of the paper.

       ***Nuance 6***
       If you are using Modsoft and a mouse in a Windows environment, make 
       sure you are using the full screen display. If you use partial
       window mode, the mouse movement will appear to have lost 
       synchronization with the window.

       
                     
                     NEW FEATURES IN MODSOFT 2.51

       1) Support of the M1 Momentum PLC line.

       2) Momentum Magnum controllers are not available at the time
       of this software release for commericial applications.  The
       selection in the configuration area is for the Beta customers.
      
       3) Support of a new Micro controller 612-04.  (This controller
       does not have a Save Program to Flash feature available)

       4) Modsoft will not allow any empty slots when programming the 
       Momentum I/O bases.

       5) Due to the M1 series PLC, Peer Cop is now available in 
       Modsoft Lite version.

       6) If you have a module type in the IBSS network that is not yet in
       Modsoft's database files (such as a BK module), Modsoft will display
       a module line with "Not in File".


                          FIXES AND CHANGES

       The following changes and fixes were made to Modsoft from
       version 2.4->2.51
  
       1) The bottom output of the FTIO function which was incorrect in 
       the tracking help has been corrected.

       2) The help screen for DDI 353 10 voltage has been corrected

       3) The Symbol Table file has been corrected to allow increment
       and decrement of the previously edited reference.

       4) When loading Flash exec into the CRP module while waiting for
       node to rejoin link in kernel mode, user could get message
       "Node failed to Enter Kernel mode" but waits for node to rejoin
       normal mode.  Comm activity lite was not flashing.  This happened
       intermittently. This has been corrected.

       5)Communications with Map3 has been fixed.

       6) Upload from a Q424 with greater than 32767 registers would not
       transfer any data above 32767 registers.  The actual problem
       was that the Reference Data editor couldn't read the uploaded
       file.  This has been corrected.

       7) Help screens corrected for AD16->DV16, TEST and ITOF.  It should 
       now read that these Builtins use up to 65535 registers.

       8) "Online Editing Timeslice field has been changed to "Online LL
       Edit Timeslice"

       9) The Program Library file list can now support over 116 program
       files but no more than 252 files.

       10) Global Input Index for PeerCop now shows 1 to 31.

       11) Search in Ladder does not support partial search on a fragment
       of a symbol.

       12) Prog File Settings->Single Load to Table of Symbols was only allowing
       125 files.  This has been corrected.

       13) Help for MIC132 said MIC312.  This has been corrected.

       14) If a user created a new program and went to RDE, edited some references
       they would see displayed the old references.  This was due to Modsoft not
       deleting *.tmp files.  This has been corrected.