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PDD.EXE Version 2.10


April 6, 1991

(C) Copyright 1991 by Tim Palmquist


/DIR  [/FULL | /WIDE] 
/KILL [filename] 
/LOAD [filename] 
/READ [filename] 
/SAVE [filename] 
/WRITE [filename]


Quick Reference
Why use PDD.EXE?
Required Hardware
Atari Portfolios
Distribution and Registration
List PDD files
Loading PDD files
Saving PDD files
Killing PDD files
Formatting PDD diskettes
Duplicating or backing up diskettes
Default configuration
Complete list of PDD commands
How it happened.

PDD.EXE is available from: Tim Palmquist 6005 Chandler Way Bakersfield, CA 93307-5509 (805) 837-8730 CompuServe 76517,1546


If you use a Tandy "PDD" (Tandy Portable Disk Drive or Tandy Portable Disk Drive 2) and you own a PC compatible computer, you probably already know why it would be convenient for you to be able to access your PDD data files from your PC. But why use PDD.EXE? Why not use one of the other PDD access programs, such as LapDOS?

Although both programs accomplish many of the same tasks, the concept behind PDD.EXE is quite different from the design of LapDOS. (In fact, it was my own experience of difficulties with LapDOS which motivated me to create PDD.EXE.) Most importantly, PDD.EXE is command-line-driven. (In other words, all commands for accessing the PDD must be entered from the DOS prompt.) Some users are irritated by this fact. However, because of this feature, PDD.EXE functions may be transparently integrated into other applications, or you may setup batch files to handle PDD operations. Such tasks could not be accomplished with LapDOS.

In addition, PDD.EXE is completely flexible regarding filename access, while LapDOS does not allow filenames with such common extensions such as ".CA" to be saved to a PDD.

LapDOS does include some capabilities which are not a part of PDD.EXE. Data format exchanges with Thinktank and Idea! are supported, as well as renaming of PDD files and viewing PDD files on screen. If you value these capabilities, you may wish to use LapDOS instead of PDD.EXE.

PDD.EXE allows full PDD "disk-image" files to be loaded and saved, providing an easy method for PDD disks to be duplicated or backed up. This "disk-image" may even contain files such as the PDD2 system file, which cannot normally be accessed from a PC. LapDOS does not include any disk-image handling functions.

In spite of LapDOS's menu-driven approach, I actually find PDD.EXE easier and more convenient to use (though I am sure that some may disagree on this point). Due to PDD.EXE's design, I can now easily access my PDD files without the interruption which is created by loading and running LapDOS.

In summary, LapDOS and PDD.EXE are two different approaches to PDD data access. Depending upon your situation, you may decide to use only LapDOS or only PDD.EXE, or both.


Without the patient assistance of several beta testers, especially Bill Huffman, PDD.EXE would not have operated well when accessing PDD1 disks from some types of 386 PCs. Many thanks to Bill Huffman, Jim Scheef, Gene Nestro, and the others!


PDD.EXE is designed for accessing a diskette in a Tandy Portable Disk Drive or a Tandy Portable Disk Drive 2, from an IBM PC/XT/AT or compatible computer. You must attach the PDD cable to your PC's COM1 or COM2 port connector. Most computers will require a gender changer (Female-to-Female); some computers may require an adapter to fit the 25-pin PDD cable to the 9-pin PC COM port. Because of potential voltage incompatibilities, it is possible that some PCs may not be able to access the PDD without a special converter (such as the "cable converter" included with LapDos). However, none of the PCs tested have been found to require such a converter. (If your computer requires the converter, please notify Tim Palmquist at the address listed below.) You must assume all responsibility for determining that PDD.EXE will function properly on your computer, with or without a converter.


Many users have expressed interest in using PDD.EXE with an Atari Portfolio. Please note that at this time PDD.EXE will NOT work with Atari Portfolios.


You may freely distribute PDD.EXE in any manner, as long as you do not charge anything. PDD.EXE is shareware, not public domain or freeware. You may use PDD.EXE for 30 days without registering, so that you may evaluate its usefulness. However, if you continue to use PDD.EXE over 30 days after you have acquired it, you must register. When you register PDD.EXE, you will be notified of any future projects or updates, when available. (A menu-driven interface is among the projects being considered.) You are welcome to call or write if you have any questions or comments.

To register your copy of PDD, please send $10.00 to:
Tim Palmquist
6005 Chandler Way
Bakersfield CA 93307-5509

Features of PDD.EXE Version 2.10 include:

- List PDD diskette files
- Load files from PDD diskettes into PC
- Save files to PDD diskettes from PC
- Overwrite existing files on PDD diskettes (optional)
- Kill PDD diskette files - Format PDD diskettes
- Duplicate or backup PDD diskettes
- Flexible default configuration for COM port and baud rate


To list PDD diskette files, type option "/D" or "/DIR" after the PDD command. Optionally, you may enter file specifications following "/DIR". File specifications may include wildcard match characters "*" or "?". A question mark "?" character will match any character in a filename, and an asterisk "*" character will match any group of characters in a filename.

PDD includes two directory options: wide and full. If you type option "/F" or "/FULL", the directory will list one filename on each line, with file size and file type information displayed. If you type option "/W" or "/WIDE", the directory will list several filenames on each line, but no file sizes or file types will be displayed. The default directory option is "/FULL".


 To list all files on a PDD1:  PDD /D
 To list all files on a PDD2:  PDD /B0D /B1D
 To list all .DO files:  PDD /DIR *.DO
 To list all .DO and .CO files:  PDD /D *.DO *.CO
 To see a "wide" directory:  PDD /DIR /WIDE
 To see a "full" directory:  PDD /DIR /FULL


To load PDD diskette files, type option "/L" or "/LOAD" after the PDD command, followed by file specifications for the files you wish to load. File specifications may include wildcard match characters "*" or "?". A question mark "?" character will match any character in a filename, and an asterisk "*" character will match any group of characters in a filename.


 To load all files from a PDD1:  PDD /L *
 To load all files from a PDD2:  PDD /B0L * /B1L *
 To load all .DO files:  PDD /LOAD *.DO
 To load a file called "TEST.BA":  PDD /L TEST.BA


To save files to a PDD diskette, type option "/S" or "/SAVE" after the PDD command, followed by file specifications for the files you wish to save. File specifications may include DOS wildcard match characters "*" or "?". Please note that the DOS "*" wildcard does not function in exactly the same manner as the PDD "*" wildcard. (However, DOS-style wildcards may be used without difficulty when accessing PDD files.)

If you attempt to save a file which already exists on the PDD diskette, PDD will display an error message: "File already exists". If you are sure you want to overwrite the existing files, you must enter the "/KILL" or "/K" option before you enter "/SAVE". If you never want to see the error message "File already exists", you may set the default configuration to overwrite existing files by including "/KILL" in the PDD environment variable (see the section below on "defaults").


 To save all files in the current directory to the PDD: PDD /SAVE *.*  
 To save all .DO files from the \LETTERS directory:  PDD /S \LETTERS\*.DO
 To overwrite PDD's "TEST.BA" with DOS file "TEST.BA":  PDD /KS TEST.BA



To kill PDD diskette files, type option "/K" or "/KILL" after the PDD command, followed by file specifications for the files you wish to kill. File specifications may include wildcard match characters "*" or "?".


 To kill all files in bank 0 of the PDD:  PDD /BANK0 /KILL *.*
 To kill all .DO files in bank 1 of a PDD2:  PDD /B1 /K *.DO
 To kill PDD file "TEST.BA":  PDD /K TEST.BA



To format a PDD diskette, type option "/FORMAT" after the PDD command. The format command may be followed by any other command, such as commands to save files to the newly formatted diskette. PDD.EXE will automatically format unformatted diskettes when disk images are being saved.


 To format a PDD diskette:  PDD /FORMAT
 To format a PDD diskette, then save "TEST.BA" to PDD:  PDD /FORMAT /S TEST.BA



To backup PDD diskettes to your PC, type option "/READ" after the PDD command. All data on the PDD diskette will be loaded into a disk image file on your PC.

To duplicate a PDD diskette, you must first "/READ" the original diskette's image, then put in the target diskette, and "/WRITE" the diskette image to the target diskette.


 To load diskette image into "ACCOUNTS.IMG":  PDD /READ ACCOUNTS.IMG
 To duplicate a diskette:  
 Type: PDD /READ
 Insert new diskette.



PDD.EXE may be easily configured for your system's needs. Before PDD.EXE processes any commands you have entered on the command line, it first processes all commands which have been entered into the "PDD" environment variable. In this way, you may easily setup PDD to default to the correct COM port and baud rate which you use. Other defaults may also be entered, such as "/K" to force existing files to be overwritten by "/SAVE"s.


 To setup PDD on COM2 at 9600 baud:  SET PDD=/COM2 /BAUD9600
 To setup PDD to overwrite existing files:  SET PDD=/K /L
   For best results, you should include "SET PDD=" (followed by the options which are appropriate for your system) in your computer's "\AUTOEXEC.BAT" file.



 Option  Abbreviation  Function
 /BANK1  /B1  Access files on PDD2 diskette Bank 1
 /BANK0  /B0  Access files on PDD2 diskette Bank 0
 /BAUD9600    Communicate with PDD at 9600 baud
 /BAUD19200    Communicate with PDD at 19200 baud
 /CASE  /C  Set PDD to case-sensitive (for advanced use only)
 /COM1    Communicate with PDD on COM1
 /COM2    Communicate with PDD on COM2
 /DIR  /D  Display filenames from PDD diskette directory
 /FULL  /F  Set directory display to "full" format
 /FORMAT    Format PDD diskette
  /HELP  /H  Display PDD options
 /INFO   /I  Display PDD program information
 /KILL  /K  Kill files on PDD diskette and set to overwrite files
 /LOAD  /L  Load files from PDD diskette
 /READ  /R  Read entire PDD disk image
 /RETRY3    Set to retry 3 times after communications errors
 /SAVE  /S  Save files to PDD diskette
 /TYPEx  /Tx  Set PDD file type to 'x' (for advanced use only)
 /WIDE  /W  Set directory display to "wide" format
 /WRITE    Write entire PDD disk image
 /1    Set disk image read to load PDD-1 compatible image from PDD2 diskette



I am not the author of PDD.EXE. In fact, as far as I can tell, nobody created PDD.EXE. No source code for PDD.EXE has ever existed. Allow me to explain.

A few years ago, one of my clients requested a program to communicate with a Portable Disk Drive from his PC. I tried LapDOS, but it could not be successfully integrated with my client's existing system. I needed something more flexible, preferably source code. A few days later, I was doing some routine maintenance on my PC's hard disk, when I discovered a file that I hadn't noticed before: "PDD.EXE". Curious, I tried it out. Imagine my surprise when I discovered that this program would actually communicate with my Portable Disk Drive! What a coincidence! But where did PDD.EXE come from? I was sure I hadn't copied it from any diskettes or downloaded it from a BBS, so how did it get on my hard disk?

At once I began an investigation into the background of my uninvited visitor, trying to locate its author, with the hope that I could persuade her or him to provide me with the source code. During the course of my investigation, I discovered several older versions of PDD.EXE, with obvious bugs which did not exist in the latest version. After analyzing these programs and comparing them with each other, I came to an incredible conclusion: PDD.EXE was a different kind of program than had ever been seen before. It appeared to be the result of some strange kind of self-mutating code, which, over time, had actually succeeded in adding additional features to itself while eliminating its own bugs!

It was then that I realized that if I could trace this code down to its origin, I could make a breakthrough discovery: self-debugging, self-maintaining code! I'd never need to debug another program. I could give up programming and take up fishing.

Over the next few months, I discovered several more older versions of PDD.EXE: more links in the chain toward the elusive origin of this program. One day, I discovered a small utility program PDDTEST.EXE, which simply checked to see if the PDD was currently available on the COM port. I knew when I found PDDTEST.EXE that I was getting close to the beginning. After years of research, I finally traced the origins of PDD.EXE all the way through the most primitive utilities, until I found the origin: a single bit, sitting in my root directory. I stared in awe. That single bit had the potential of becoming the Mother of all programs!

I went out and bought the fastest 486 computer I could find, with a 400MB hard drive. Then I copied the Mother bit to the root directory. As I watched in amazement, that one Mother bit transformed itself, through a process of random mutation, into a complete family of full-featured, bug-free programs for handling every need imaginable.

I had discovered the Source of all code.

* * *

Back to reality. As we all know, computer programs don't create themselves from a Mother bit. It is fantasy at best, and foolishness at worst, to even consider the thought. (Even the most sophisticated "artificial intelligence" programs can all be traced back to an intelligent HUMAN source.)

How, then, could we ever entertain the concept that human life, and all of the other life which surrounds us, just "evolved" from a long series of random mutations? Look at the trees, the mountains, the animals; look in the mirror! Everywhere you look, the work of a loving Creator is evident.

Just as PDD.EXE was carefully created by me, you were carefully created by God. Acknowledge Him today as your Source, realize your own inadequacy and accept His gift of permanent life through Jesus Christ.

If you want to know more about God, read the book of John in the Bible. Or, contact me; I'd be glad to help.

Have a nice life!

Tim Palmquist 6005 Chandler Way Bakersfield CA 93307-5509 (805) 837-8730 CIS 76517,1546


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