In bringing up a brand new out of the NEVER OPENED BOX phi-deck drive I was looking through some old tapes and ran across a copy of PHIDOC.TX which contains the updated documentation for PHIMON. This version "communicates" in hexidecimal instead of octal as well as supporting updated commands.

Enjoy


<PHIMON-H>: Hexidecimal PHIMON Ver 3.0
An addendum to the PHIMON OPERATING SYSTEM Manual

P.J. Ferrell K7PF


I. INTRODUCTION

<PHIMON> is a superior tape-based Operating System, exceeding the capability of man y disk-based systems. The modifications described herein are only extensions, and retain the design philosophy so ably expressed by David Bryant, the originator of <PHIMON>.

Some internal addresses have been changed due to 8080 code being replaced by more concise Z-80 instructions. Where possible, however, compatibility with previous versions was maintained. With the exception of HEX communication instead of Split-Octal, the user will notice little in the way of difference between <PHIMON> and <PHIMON-H>.


II. COMMAND EXTENSIONS

1) The DAte command replaces the HElp command.

2) The LOad command allows other than .GO extension, and permits optional starting address override using "@":

Format: >LO#n NAME.EX @addr

where addr is a two-byte hexidecimal address used instead of FPAGE (normally obtained from the header block).

3) SAve command allows other than .GO extension.

Format: >SA#n NAME.EX xx-yy*sa

Note that if .EX is not specified, a .GO default is assumed for LOad and RUn as well as SAve. If repeated saves of the same file are desired, all after the first can be accomplished by:

Format: >SA#n

NAME.EX and xx-yy*sa then default to their former values.

4) The ZEro command allows cassette length specification.

Format: >ZE #n Cxx
or: >ZE! #n Cxx

Legal values for xx are 30, 45, 60 and 90. If the Cxx is omitted, a C30 is assumed. Note the space following the #n is not optional, since nCxx is a perfectly legal HEX quantity, and GETNUM will return and xx for drive number!

5) The DName command allows changing (or adding) a cassette directory tape name. Automatic date insertion is optional.

Format: >DN#n

Tape drive selection is made with the #n (defaults to 0). the directory is read and the current name (if any) is displayed. A new name may then be entered. At any time, the "ESC" key will causes a return to PHIMON without modifying the present directory name. If name input is terminated with the RETU?N key, the current PHIMON date is included automatically. This autodating feature may be avoided by terminating input with the LINE FEED key rather than wit the RETURN key.

6) The DRefresh command will re-display the currently memory-resident directory listing. It will load the DIRECTORY overlay if necessary.

7) DTO/DTH has been replaced by STEPER. If the top 8K of memory is available, a DT command will execute STEPPER if resident or load and execute it if not.

III. ADDITIONAL FEATURES

1) All numeric communication with PHIMON-H is in HEX, including page numbers for the SAve command.

2) Upon booting up, <PHIMON-H> display as the current version's build date and asks for today's date. Date entry is free field, with any delimiter echoing as a /. Each program saved under this system includes the date in the header block. The LOad and RUn commands will display the save date after reading the file header block.

3) When initializing a directory with the ZEro command, a tape-name is requested. This may include up to 48 characters, and the current date is automatically appended. The DIrectory command will display the tape name along with the content listing. To correctly list a directory, <PHIMON-H> requires a name (try an old tape and see), but adding a name does not otherwise affect the old directory (try that too). Use the "DN" command described above to add a name. The name resides in the last half of the last block of the directory, reducing the maximum number of directory entries from 101 to 88.

4) The new PIP is one page smaller (8080 to Z-80 again) but has some new features. Rather than blindly continue after an error, it requests: "(SPACE) TO CONTINUE". Any other character will cause PIP to finish up with what it already has transferred.

5) An NMI (non-maskable interrupt) will force a re-boot of PHIMON without otherwise affecting memory content. This feature is best appreciated with trying to save an hour's worth of input with a clobbered copy of PHIMON.

6) Existing system tapes may be converted to <PHIMON-H> without disturbing their content. Place an old tape in drive #1 and a new <PHIMON-H> tape in drive #0, and type:

>BU #1

The boot-code and overlays of the old tape will be replaced by that of <PHIMON-H>.

Just added a very intersting article from "Brown Box Journal", March 1982 describing digital group history from Microworks point of view. The article can be found here or you can find it in the History section of the articles page.

Early 2005: I was fortunate enough to find a system that was still running albeit in a strange configuration. When I received the system, it was in pretty "odd" shape. While it seemed to work well, the guts were very unusual for a dg system. The normally fragile memory boards had been replaced by a CPU piggyback card with 64k on two chips! There was also a special purpose PROM board that held three switchable PROMs. The case was in good shape with only a few scratches. The front panel was immaculate as were the other anodized aluminum parts. The toughest part was the keyboard which had some keys that were intermittent and the whole thing was yellowed from smoking.

Since the system was working, I was hesitant to just tear the thing apart so I started with the keyboard. With a great deal of advice from Bryan Blackburn, I carefully disassembled the keyboard and spent days cleaning each individual key cap with #0000 steel wool and various cleaning agents. I carefully cleaned the circuit board, reassembled and tested it out.... perfect!

Fastforward to early 2007: A couple of moves and several other obligations kept me from this most enjoyable hobbie for several yeas. In that time I was fortunate enough to find two other systems, both seriously neglected but with some good boards and other stuff. One find included two brand new Phi-Deck drives still in the original boxes!!!!

Now the real fun begins. I have time to get back to restoring these venerable old machines.


I plan on (re)starting by restoring one of the non-working machines. I'll start with the keyboard which is totally dead except for the U/C light that stays lit.

Keyboard Restoration

Bryan Blackburn has a page devoted to Keyboad Restoration which has some very good tips.

Keyboard restoration is the most tedious, frustrating part of restoration. The process goes something like this:

1 - Disassemble keyboard cabinet
2 - Remove all keycaps
3 - Remove key plunger housings
4 - Carefully remove all foil
5 - Clean everything
6 - Fabricate new foam pads
7 - Glue foam pads to key plungers
8 - Test each plunger
9 - Reassemble

Sounds easy doesn't it? Perhaps this is a good time to talk about patience. Restoring a keyboard can take lots of time and effort.

(1) Disassemble Keyboard Cabinet

Remove all of the screws holding the aluminum housing in place and carefully remove the keyboard and the plate to which it is attached. Disconnect the 18 pin dip connector at the top left of the keyboard.

(2) Remove all Keycaps

The only way to remove the key caps is to gently (or not so gently) pull each cap off of the plunger by grasping the key and pulling up. There will be a spring behind each cap that maintains upward tension on the key when at rest. Notice that the often used keys like "return", "rub", etc. have a larger yellow spring than the other keys. This will become important during reassembly. If you do not have another keyboard to look at during reassembly, it's a good idea to take a picture of the assembled keyboard or take good notes of key position that can be referenced during reassembly.

(3) Remove Plunger Housings

The grey plunger housings are held on by two or three machine screws that go through the printed circuit board with a small nut on the rear of the board. Carefully unscrew each while holding the housing. Remove the housing and remove the white plastic plungers. As far as I can tell, other than the U/C button, it does not matter which plunger you use for which key, so organizing them is not important. It is however important to keep the plunger housings in the correct order. I always number the housings with a sharpie beginning with "1" on the lower right corner.

(4) Carefully Remove Gold Foil

You'll find that the gold foil backing can be very, very, very, very delicate. I've only seen one keyboard that had the foam backing in tact. If the foam backing is in tact and shows no sign of degradation (unlikely), you can skip steps 6 and 7. If you can easily pull the gold foil away from the plunger, it's probably a good idea to replace them all. You'll likely end up with a pile of gold squares with a dusty gray matter on the back side as pictured here. It's important to note that the foil backing must be in perfect shape to reuse. If you accidently break a foil, do not try to use it! At best the key may work just fine, but more likely, you'll get the whole keyboard back together then have a key or keys that aren't very reliable (argh!). If you do damage some of the foils, you can replace them with aluminium foil, but you'll change parts of the keyboard from capacitive to conductive which I'm not sure is a good thing!!! It does work, but I'm not sure of the future consequences. Did I mention patience? Be very careful with the plungers and foils as replacing either is next to impossible.

(5) Clean Everything

The gunk (glue and residual foam) can be scraped from the back of the plungers with your fingernail or an exacto knife. Be careful not to break the ears off of the plungers. After that, I dump all of the keys, plungers and springs into soapy water and clean using an old soft toothbrush. I've restored one keyboard that was exremely yellowed by cigarette smoke by using #0000 steel wool and lots and lots of elbow grease. The letter and numbers are molded into the plastic key caps so you can actually remove the outer layer of the keycap without ruining the lettering. Have I said anything about patience lately? This process can take many hours. I spent about 5 or 6 evenings with steel wool working on each individual key cap. The keycaps will not be as shiney as they were before, but the yellow stains will be gone...... Take this at face value. This was my experience, your mileage may vary....

After the plungers, keycaps and springs have been cleaned, be sure to rinse in clear water to remove all of the soap or cleaning solution, shake off excess water and place on a paper towel to dry. Now that you're finished with the easy part, it's time to move on to cleaning the foil

The foils are probably sitting in a pile with lots of foam dust falling all over you work area (see photgraph). I clean them in two steps; 1) using a soft toothbrush I gently hold the foil by one edge and CAREFULLY brush the foam residue off of the back side. I believe that Bryan Blackburn leaves the last of the residue on the foil as it helps strenghten the foil (and keeps it from curling up). Due to the nature of the new foam that I use, I've found that the residue keeps the foil from sticking completely to the new foam, so, I use acetone and lots of Q-tips to very carefully remove the glue residue from the back of the foil. And, yes, the foil will curl up and be very fragile following this step.

(6) Fabricate new foam pads

I've tried several materials to replace the foam and found that 3/16" thick, soft weatherstripping with adhesive on one side works well. Stay away from "mounting tape" as the backing does not "give" enough to conform to the printed circult board to allow the keys to work reliably. The 3/16" foam will give the keys on thekeyboard a very short stroke ~ 1/16". If you like a longer throw on your keys, use 1/8" thick foam instead. I cut sections about 6" long from the role of weatherstripping and carefully unroll the gold foils and place them on the sticky side, gold side up.

If you have damaged some of the gold foils, cut a piece of thin aluminium foil large enough to make replacements (plus a few extra) and stick it (shiny side up) to the weatherstrip. Cover each strip with wax paper pressing firmly to 1) assist in sticking the foil to the foam, and 2) stick the wax paper to the foam where it is exposed. The wax paper is important to keep the foil in place while round holes are punched in the center of each foil. Using a simple round hole punch available at any office supply or "Hobby Lobby", carefully line up the punch with the hole in the foils and punch holes in each foil. Remove the wax paper.

As I'm somewhat artistically challenged, and can't draw (or cut) a straight line without a ruler, I machined this handy "contact jig" from aluminium for the express purpose of cutting new contacts. It's exactly the size of the foils and is used as an outline by which to cut the foil and foam.

You'll also need about three or four new blades for your exact-o knive as this foam, paper, foil combination blunts blades pretty quickly. If you don't have the nifty cheater that I made, you'll have to use a metal ruler and or a steady hand to cut your foam. With this jig, I simply cover the foil, compress the foam completely and cut around the perimeter with the exact-o knife to get the foil to a square shape. Next cut the "edges" of the indention with the exact-o knive, finally cutting the inner edge with a 3/16" wide chisel or carving tool.

If I haven't mentioned patience lately, this is a good point. This is very time consuming, but care here will significantly cut down on reassembly troubles. Compression of the foam greatly assists adhesive effectiveness as well.

Cleaning the printed circuit board can easily be accomplished with a soft brush to remove dust and dirt. In addition, the contacts on the board should be cleaned first with an old fashioned pencil eraser then with a mild solvent (I use contact cleaner and carefully wipe off all of the residue).

I also clean all of the machine screws, nuts and small white stand offs replacing anything that is rusted or corroded.

(7) - Glue foam pads to key plungers

You should now have a pile of clean keycaps, springs, machine scres, nuts, plungers, plunger housings, and brand new plunger pads. At this point I usually layout all of the parts (except the new foil and foam pads) as they will be reassembled. I then line up about ten foam pads (gold side down) on a paper towel (I've tried wax paper with terrible results) and spray lightly with 3M general purpose spary adhesive. IMMEDIATELY (you'll have approximately 1 minute) AND CAREFULLY align and press the plunger face onto the back of each new pad. Be sure that the pad and plunger face are properly aligned or reassembling the plungers into the plunger housing will be very difficult. You can move the pad around on the face of the plunger slightly before the adhesive dries.

(8) Test each plunger

I like to be sure that each plunger/foam/foil combinaton will work before I reassemble. This can easily be accomplished by attaching the keyboard to your computer (yep without the keys!), loading basic, and carefully touching the face of each plunger to one of the silver pads on the printed circuit board. You should see a character appear on the screen. If not try rotating the plunger 90 degrees and try again. If none of the keys work, you may have other problems, not related to the plungers.

(9) Reassemble

Almost there..... Reassemble the plungers, housings, springs and keycaps one housing at a time, attach the housing to the pc board turn on the computer and test as each new housing or row are added. It's a lot easier to find a malfunctioning key immedately rather than when you get the entire keyboard back together.

If you've done everything right, you should now have a working keyboard......

Official dg keyboard documentation in PDF format.

Actual notes in the HELP WANTED section of the first issue of BRIDGE. The last entry asking for help when the oven is turned on was an actual problem suffered by more than one DG enthusiast..... These really were the pioneering days!


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Mr. A. Einstein writes: How can I prevent the interference that appears on the TV sets throughout my house whenever I turn on my Digital Group System?
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HELP !!! Is there a genius out there who can help me with this seemingly unsolvable problem? What do you say to the little woman when she yells down to you the following pearls "When are you going to stop playing with that fool computer and spend some time with me and the kids" ..... or "Do you want to be married to me or to the computer"? Please wire your answer as soon as possible. It's getting mighty cold at night and it's only JUNE.
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Can someone please supply me with the correct fix so that Maxi doesn't bomb out when loading in an applications program? Signed Lonely, forlorn, discouraged and dying to balance my checkbook.
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My system bombs out whenever my wife puts on the oven. Is there another solution besides eating out all the time? Send all replies to; Ronald McDonald Box 316, Woodmere, NY 11598
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The following entry is the RANDOM BITS editorial from the very first issue of "BRIDGE" newsletter. I will post interesting and usefull articles as text so that they can be searched.....

RANDOM BITS

In anticipation of my first attempt as an editor, I had prepared a long drawn out letter of introduction telling of my reasons for starting up the DG Independent User's Group and this newsletter. However, as the mall starting coming in, Ireallzed that many of you were expressing my thoughts precisely, so I decided It would be much better if I let you do the talking. Please keep writing because we'd all like to know what you are doing. (Besides as a bonus it makes my job much easier).

I'd like to start out by giving you some background material. I've had my Digital Group system up and running since May '77. It consists of a Z-80 CPU, a 64 character board, 34K of static RAM, a single Standard Disk ( Comp 1 ) all built from kit form, a modified Sander's keyboard, a LA35 DecWriter II, a 12" CRT from Computer Warehouse, and my latest addition, a surplus Model 73-1 Selectric. Softwarewise, I've been suffering with the usual stuff supplied by DG ( Maxi Basic, Diskmon, WOPROC, etc ••• ) and have been sticking to Basic for my own applications. I'm definitely more hardware oriented than software. Actually, I'm not that sure that I would be classified as a hardware type either. To play it safe I'll call myself a "systems engineer".
My primary reason for getting started as a computerlst was to be able to do things at home that I couldn't do at the office,Ci.e. enjoy doing things, I wanted to do.) I didn't have much space or money available; however I soon learned that I would have to alter both these situations. I'm now interested In providing computerized services to small business and I am presently printing up invoices for one of my neighbors. I hope to be able to handle statements and type business letters in the near future.
Now ••• for the gory details. After checking with my local banker, post office official, journalists, printers, accountant, etc ••• the cost of membership was set at $6.00. This entitles each member to all privileges of the group (to be determined) plus a subscription to the first six issues of this newsletter, which I plan to issue on a monthly basis.

Please fill out the application form on the last page and send it in with your payment. In addition, "BRIDGE" is announcing the first Independent User's Group contest of the '78 season. If you check the masthead you will notice some blank spaces after the letters. I thought the Acronym was great but couldn't think of the right words to go along with It. Fill in the blanks on the application form and you may win the free membership worth $6.00. A distinguished panel of judges ( my wife and two daughters ) is ready to pick a winner.
In conclusion, to keep this an " INDEPENDENT" User's Group I have made no attempt to contact The Digital Group for mailing lists, help, etc •• and mean to keep it that way. Remember, the purpose of this group is to help one another. Let's keep the lines of communication humming. It is you who will make this newsletter a success. Till Vol. 1 No. 2