Executive DNC Software Notes

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Executive DNC software combines the power of PC compatible computers with Rybett's Camstore Behind the Reader technology to give all NC and CNC machines the ease and reliability of modern communications. Executive DNC handles all types of shop data including both EIA/ASCII g-code files and binary exec files. The software can service an entire shop full of machines from a single DNC server or it may run on many computers networked to the factory LAN. Executive software can function from a single computer port, from multiple COM or LPT ports, through simple ABCD mechanical switches or automatic code activated switches. If loaded onto a laptop or backup computer, Executive DNC can keep your shop running even when your network or server has shutdown. Executive DNC runs under DOS, Windows 3 and Windows 95/98. It will not work under later versions of Windows such as NT or XP.

Topics: [Software Uses]  [Binary Files]  [Merge Names]  [Hooks]

PROGRAMMING SERVER: Executive runs on your programming computer and is called whenever a file transfer is needed. Suitable for light duty or small shops that can afford to suspend the programming tasks. Executive DNC runs under DOS, Windows 3 or Windows 95/98. It will not run under later versions of Windows such as NT or XP.

DNC SERVER: Executive runs on a shop computer (such as our own Rybett Shopbox) dedicated to DNC file transfer. The DNC server is connected to a number of machines via a COM port switch. Programming updates are sent over a simple network link between the DNC computer and programming stations.

GROUP SERVERS: Executive is distributed over several shop DNC work stations, each connected to a small number of related machines. A mixture of COM port, LPT ports and switches is supported. A factory LAN links all computers for timely revision control.

INDIVIDUAL WORK STATIONS: Executive software is loaded on shop work stations (such as Rybett Camstore 1SX hardened computers) placed at each machine site. If required, the computer is fitted with a BTR option. All computers are networked for simple efficiency.

EMERGENCY DNC LAPTOP: When loaded onto a laptop or backup computer, Executive DNC can keep your shop running when programming, server or network hardware fails. Executive DNC can load your CNC, feed your BTR interfaces and even reload the binary tape file for an NC machine that loses its executive program.


An important feature of Executive DNC is the ability to handle binary NC executive tape files. Controls such as the GE1050 and Cincinnati Big Blue require a long executive tape to load basic intelligence into the electronics much as a modern computer might require an operating system. Working with executive tapes is complicated by:

1. Most executives can only be loaded through the tape reader port and therefore require a BTR interface to accomplish this task via a DNC system.

2. The push-button and switch sequence for executive loading differs from normal g-code tape load and is usually much more complicated. And, the control is quite dumb during this process, limiting feedback.

3. Executive data is binary in nature without parity or formal error checking at the level of the tape reader. This makes saving an executive to disk storage a bit tricky. Several reads along with a file comparison is the only way to assure yourself of good data.

4. Some controls require the executive load to begin at a definite point on the tape. For instance, the Big Blue must begin on a delete code surrounded by leader. This point is usually marked by greasy thumb prints accumulated over the years. The electronic version of such a file must take this into consideration.

SAVING AN EXECUTIVE TAPE: If you are using a serial tape reader and punch combination such as a Facit, make sure you set both the reader and the software for BINARY MODE, NO PARITY and 8 DATA BITS. Disable automatic features and use cables with hardware handshakes. Since all 256 possible combinations of an 8 bit tape word may be used as binary data, there are no spares left over for DC or XON/XOFF codes.

Rybett BTR interfaces allow loading from the tape reader and may be used to save executive files. You may wish to choose a machine with a good reader equipped with reels as a loading station for all of your exec tapes. Refer to the Machine Setup Pages of the example devices defined during Executive DNC installation and/or the (M)enu feature of Machine Setup to properly configure for binary operation.

Save your tapes several times under different names and use the binary file compare option under Binary File Maintenance to verify your results. If you don't start and end tapes consistently, the comparison will fail. You may adjust the beginning and end of your files using the Binary File Editor to alter, insert or delete bytes. Note that the leader and trailer of most executive files consists of null characters, represented as hex 00 in the binary editor.

RELOADING AN EXECUTIVE TAPE: Reloading is a tedious process even when you know what you are doing and everything goes right. Now what are the odds of this when you are trying to reload the executive from the DNC for the first time? Sorry, I'm betting against you!

First, make sure everything is working on the NC control. Load the executive from the actual tape and take notes on every button that is pushed and every light that flashes. After a good trial run with tape, attempt to repeat the process from the DNC.

If the control requires that you start the tape on a particular delete or null, make sure you setup the DNC port to initialize to the value of that character. For Rybett Camstore 2/COM BTR units, delete is standard with null available as an EPROM option. For the Camstore LPT BTR, delete is the default and a -n software switch forces null. If the control allows you to begin the tape anywhere in leader, the port initialization is not important.


If you are setting up an Executive DNC backup system, it may be of value to merge the g-code settings of an existing DNC with the binary settings of your new software, giving you total capability. You may accomplish this manually by recording all of your machine names and setups on paper and then entering the data into the Executive backup software. Or, if your original DNC is Rybett Camstore or Camshare, you may proceed automatically with the MERGE utility located in the CAMB directory. MERGE is used with the following syntax:

    MERGE [level letter] [source path]

    N Machine names only (MACHNAM.TXT)
    M Names and menus (C3MENU.MNU, etc.)
    S Names, menus and setups (MACHDEF.DAT)

    PATHLIST to location of data to be merged

Executing MERGE will cause the specified source data to be added to the current setups in the Executive CAMB directory. The data in the source directory will not be altered. The old data files in the CAMB directory will be saved with an .RBI extension for safety.

As an example, if you are setting up a laptop version of Executive DNC, you may copy your existing Camshare DNC setup to floppy with the DOS command "COPY C:\CAM\*.* A:" without the quote marks. Then insert the floppy into the laptop and from the CAMB directory type

"MERGE S A:" and the new and old DNC setups will be combined.

If you are setting up Executive DNC to backup a system not built by Rybett Controls, the merge function will not work. In this case, you must simply enter the names and setups manually. It will help, if you first print out all of the setup information from your existing DNC software. For clarity, use the same machine names and directory structure if at all possible. Using a text editor, modify the MACHNAM.TXT file to fit your shop. Then fill out a Machine Setup page for each machine name using your printout as a guide. You may also press M(enu) under Machine Setup for standard Rybett setups.


The following information only applies to the current 5.0 version of Executive DNC software.

Executive software hooks allow other manufacturing applications to be cleanly integrated into the overall DNC system. These hooks provide two methods of interaction with third party software: program calls from the Executive menu and various driver/hook programs that may be run from many other software programs.

Executive DNC is built around a list of operations. This list is called the Operator Menu and may be customized by the user. Simply edit the C3MENU.MNU file to alter the Operator Menu as follows:

    (Final Prompt) Row, Column, Message
    (Menu Item 1) Row, Column, Message
    Command Line
    (Menu Item 2) Row, Column, Message
    Command Line
    (Menu Item 3) Etc.

The "Row" and "Column" are just numbers to place "Messages" on the display screen for Menu Items and the Final Prompt. The "Command Line" may be an internal Executive function or any DOS program that you wish to execute. An 8 character "Password" is optional and protects access to any Menu Item. The internal Executive functions available as commands are listed below:

    Downfile:  File selection and download functions
    Upfile:  File selection and upload functions
    Editfile:  EDIT File selection and calls EDIT program
    Filesel:  USER File selection and calls USER program
    Fileutil : File selection and utility functions
    Filecopy:  File selection and copy functions
    Machdef:   Machine Setup Page functions

The two commands Editfile and Filesel prompt for a filename, then pass this filename to the program indicated on the command line. In the case of the above list, EDIT stands for the name of any editor and USER denotes any user program name. If you don't want Executive file selection screens to precede your program, you may enter any DOS program name as a command.

Many of the programs popular in the manufacturing sector give the user means to interact with other software such as Executive. For instance, dBase allows the construction of Command Files that look very much like Basic programs. If called with a command file as a parameter, dBase will load and run automatically. So, for instance, the Executive Operator Menu could call DBASE COMFILE which would run the command file COMFILE.

Executive Driver and Hook programs allow other applications to use Executive to transfer DNC files. There are three programs that may be used by other applications.

DNCXFR.EXE file transfer driver program
CHOOK.BAT batch file using DNCXFR
MACHSEL.EXE machine selection utililty

The DNCXFR.EXE driver may be called as a command line function with parameters to specify operation, machine and filepath. The matching CHOOK.BAT hook is a simple batch file with useful comments that calls DNCXFR. Finally, MACHSEL.EXE is a program that allows a machine name to be chosen prior to calling a driver such as DNCXFR.

The DNCXFR.EXE driver can be called from the DOS command line with the following syntax to control file transfer:

DNCXFR [Machine] [Filepath] [Options]

[Machine] is the DNC name of the machine
[Filepath] is the selected file
[Options] -d Download tape file or -u Upload tape file
(And other options as required by specific drivers such as LPTBTR, CAM2 and CNC.)

Example: DNCXFR M215 C:\TAPES\XYZ123.NC -d

The CHOOK.BAT file passes parameters to DNCXFR and adds directory changes. The working portion of CHOOK.BAT is listed below:

cd \dncpath
dncxfr %1 %2 %3 %4 %5
cd \oldpath

The MACHSEL.EXE program will allow users to choose a machine name if one is not already known before calling a transfer program such as DNCXFR. The syntax of MACHSEL is as follows:

MACHSEL [Machine] [Filepath] [Program] [Options]

[Machine] is the DNC machine or ? for prompt
[Filepath] is the selected file for transfer
[Program] is the name of the transfer program
[Options] options as required by specific drivers


All of these hook programs assume that the DNC is properly configured and tested using the standard Executive DNC menu. The MACHNAM.TXT file should contain the valid machine names referenced above.