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ORIGINALLY PUBLISHED IN LIMA NEWSLETTER JANUARY 1994

 THAT "OTHER" OFFICIAL TI CARD FOR THE PE BOX
reviewed by Charles Good
Lima Ohio User Group

     HISTORICAL BACKGROUND:
    Here's a trivia question.  In addition to the disk
controller, RS232, and 32K memory expansion cards which
almost all of us have, what other TI PE box card could be
purchased in 1983 directly from TI or from most TI dealers
of that time?  Answer..The P-CODE card, first shown to the
public in January 1982 and listing for "only" $249.95 in
TI's last 1983 catalog.  With this card you can run canned
disk or tape software written by others in UCSD PASCAL (also
known as "p-Code" or the "P-System").  For a list price of
$499.95 you could purchase the P-Code card AND development
software that allows you to write your own USCD Pascal
software as well as write TMS9900 assembly language
programs.  That's right, assembly code can be written
without TI's editor assembler package using the P-Code card
and associated software.  In 1982 the P-Code card's
potential seemed enormous.  Yet now very few 99/4A users
have or will ever need this piece of hardware.  What
happened to all that potential?

    The following quote from the April 1983 issue or POPULAR
COMPUTING states what many at that time believed to be the
future potential of UCSD PASCAL.  "Immagine how much easier
choosing your microcomputer would be if any computer program
on the market would run on any machine.... Your old programs
would run on any new computer you might buy.  That's what
software engineers call portability, and it's the goal of an
increasingly popular computer operating system called the
UCSD p-System.... a universal language, a kind of computer
Esperanto that would allow a program written for one
computer to run on all the others."  Or how about this ad
quoted from the July 12, 1982 issue of INFOWORLD: "Whether
it's a Z80, 8086/8088, M6800, 6502, or you name it, the
p-System is portable across any popular microprocessor made
anywhere today.  And we don't mean just at the source code
level either.  We mean you can develop your program on any
machine, then compile to object code (p-code),  and its
totally transportable.....the only OS that runs the same
object code programs on all popular 8 and 16 bit
microprocessors.  No matter who makes them.  No matter who
uses them."

     Sounds neat, doesn't it! There should be tons of
software written on other machines will run on the 99/4A
with a p-Code card.  That was the promise.  But there is
almost no software.  What happened? Where is the p-Code
software? An interesting article by Stan Veit published in
the Dec 1992 issue of Computer Shopper tells most of the
story.  In 1980 the University of California gave Softech
Microsystems an exclusive licence to market and develop the
UCSD p-System language.  Softech got greedy, and what was
once almost public domain technology suddenly became too
expensive for almost everyone.  For example, on page 10 of
the January 1984 issue of BYTE it is noted that, "Softech
Microsystems has announced a family of newtork software
products based on its p-System operating system.  Initially
... software for up to eight users costs $750." And you had
to already own the latest 1983 version of this operating
system ($450 for EACH machine) in order to run this new
software! Suddenly nobody was purchasing the p-System or
writing any software for it.

    There is another reason for the lack of 99/4A software
that uses the p-Code peripheral.  Software written in the
UCSD PASCAL language is compiled into an intermediate code
called P-code, and this P-code is exactly the same no matter
what machine is used to develope the software.  The same
PASCAL source code typed into a variety of different
computer types equipped with a P-System interpreter will
compile into exactly the same P-code.  Each different kind
of machine has its own unique P-code interpreter which
translates the P-code into the machine's native language for
execution.  The P-code card for the TI contains the
necessary software in ROM to translate P-code into TMS9900
assembly directives.  All of this suggests that you should
be able to put disks containing UCSD PACAL software written
on an APPLE IIe, a Mac, an MS DOS machine, a Commodore 64,
an Atari 800 or ST, etc. into our 99/4A's disk drive and
have the P-code card actually run the software! There should
be hundreds or thousands of PASCAL programs out there for us
P-code card owners to play with.  Unfortunately this is not
the case.  YOU CANNOT PUT A DISK WRITTEN ON ANOTHER KIND OF
COMPUTER INTO A 99/4A'S DRIVE AND EXPECT TO RUN pascal
software. This is true even if the disk from the other
computer contains the exact same sequence of P-code 1's and
0's that would be generated by our TI's if the PASCAL source
code had been typed into the TI instead of the other
computer.  Why? The 99/4A disk controller only recognizes
disks formatted by a 99/4A or Geneve.  Our /4A's can't read
"their" disks. This is true for most computer types.  Even
though there is only one kind of p-code, there is no
universal disk format readable by all computers.

    So.....what is "portable" about UCSD PASCAL?  Well, with
some exceptions you can type in the exact same printed
program listing as source code into the PASCAL editor of ANY
computer that supports the USCD PASCAL system.  These
program listings can then be compiled into P-code and run on
different machines.  Thus, if you start with a printed
source code listing, the same software SHOULD run
identically on different kinds of computers.  Unlike BASIC,
which is only sligltly similar from one machine to another,
text oriented software written in UCSD PASCAL is supposed to
be identical from one machine to another.  I said "text
oriented" because UCSD PASCAL for the 99/4A includes
commands for graphics, speech, and sound that would not work
on other computers.

    Finally, an important reason for the lack of modern
p-Code software is the development of versions of TURBO
PASCAL for different computers.  Both TURBO and UCSD PASCAL
start with the same printed source code listings typed into
an editor and then compiled.  However, TURBO PASCAL compiles
directly into the native assembly code of the host computer,
bypassing the intermediate p-Code stage.  Software written
and then compiled from TURBO PASCAL runs much faster than
software that compiles into p-Code.  Good bye p-Code.  L.L.
Conner (317-742-8146) sells a version of TURBO PASCAL for
the 99/4A that does not require TI's p-Code card.  I have
see software listings in TURBO PASCAL for IBM clones
published in recent (1993) computer magazines.  It has been
years since I have seen any new listings in UCSD PASCAL.
------------
      TI'S OFFICIAL IMPLEMENTATION OF UCSD PASCAL

     A complete UCSD PASCAL system for most computers
includes an editor for entering program code or text
documents, some file/disk/printer manipulation software, a
compiler to convert source code into P-code, and a P-code
interpreter.  Only the P-code interpreter differs from one
computer to another.  TI chose to unbundle these parts and
sell them separately.  A minimum system consists of only the
P-code card itself, which contains the interpreter in ROM.
The TI version of the P-system editor and file manipulator,
and the P-code compiler are extra cost items in TI 99/4A
catalogs.  With only the card 99/4A users could purchase and
RUN commercial PASCAL software on disk or tape.  Back when
TI hardware cost BIG BUCKS there were some folks who
purchased a PE box but couldn't immediately afford a disk
system.   In 1982/83 the $249.95 list price for TI's p-Code
card (without development software) looked like a real
bargain.  Softech was at that time charging $450 PER MACHINE
(with development software) for a P-system on every other
type of computer.
------------------
    AVAILABLE APPLICATION SOFTWARE FOR THE P-CODE CARD:

    What's available that can be run with just the P-code
card without the other "sold separately"  P-system
development software?  TI actually sold PERSONAL TAX PLAN,
an income tax preparation software package written by a
group of CPA's who called themselves Ardvark Software.
Personal Tax Plan was also available for the Apple II and
probably some other personal computers of the day.  I have
an original copy of the TI version, ($99.95 in TI's last
1983 catalog) complete with documentation, all contained in
a large three ring padded TI binder.  This was based on 1983
tax laws and probably isn't usable for computing federal
income taxes in the 1990's.  Items covered include the joint
filing credit if both spouses work and income averaging,
neither of which are part of the 1992 tax code.  For an
extra $45 you could obtain a toll free phone number that
give you up to one hour of over the phone help in using the
software from a CPA.  Additional hours are only $40.  My
docs state that this $45/hour service does NOT provide tax
advice, just aid in running the software.

     TI's last 1983 catalog also lists TI PILOT ($79.95), a
language written in UCSD Pascal designed for use in computer
aided instruction in schools.  TI PILOT was never released,
but I have a copy of the software and its user
documentation.

    Also in the works from TI for the P-code card was a word
processor that came as a text editor and a separate
formatter.  The editor of this "never released" software was
similar to TI's regular UCSD Pascal editor, and the
formatter had capabilities similar to those of the TI Writer
formatter.  I have a copy of this UCSP Pascal word
processor, and it has one BIG problem.  You create text with
its editor and then save the text to a disk file.  You then
switch to the formatter to print the formatted text.  You
can't print directly from the word processor's editor.  The
problem is that the formatter doesn't work with modern
printers! One version of the formatter is for "Diable 1650s
and 630s (or any variable pitch printer)" and the other
version is for "TI810 printers (or any fixed pitch
printer)".  I have no idea what "fixed" and "variable" pitch
printers are.  Setting Pascal to look for a PIO printer
(instead of the default RS232) doesn't help with this
formatter.  A word processor isn't much good if you can't
print its text! The regular pascal editor, the one that is
used to enter source code, makes a very usable 80 column
word processor.  Printing text from the regular editor is
not difficult.

    TI also had for the p-code card a "three dimensional"
spread sheet called FREEFORM that allowed the user to create
templates in rows, columns, and pages.  "Pages" is the
third dimension.  Mathematical calculations can only be done
in two dimensions (rows and columns), so the actual use of a
three dimensionsl matrix is somewhat limited.  The P-code
word processor and spread sheet never made it into published
TI catalogs, and were never released.  This material is now
in the public domain.  The Lima group has this never
released software in its library as well as a hard copy of
the 1982 documentation.  We also have the source code of
FREEFORM as p-System text files.
---------------
    OPERATING UNDER THE P-SYSTEM:

    The P-code card turns the 99/4A into a completely
different and mostly unfamiliar computer.  Execution is
SLOW, in part because much of the p-System must be loaded in
sections into memory from disk.  There is lots of disk
activity. If you want your computer to behave like a normal
TI there is a switch on the back of the P-code card that
makes the card transparent to the rest of the computer
system.  If the P-code card is switched to the ON position,
then when you turn on the console the P-code card captures
the system.  You don't see the usual TI title screen and if
you have a CorComp disk controller you don't see the CorComp
title screen either (CorComp controllers are notorious for
usually capturing control of the 99/4A before other sofware
can be run).  Instead of a title screen the disk drives
grind away and the computer beeps several times as the
P-code card checks the first three drives to see if a
P-system formatted disk is in the drive.  After about 45
seconds of this either the disk in the first drive
automatically begins to execute if it contains a Pascal file
called SYSTEM.STARTUP.  If not, a list of available Pascal
commands appears at the top of the screen.  From this list
of commands the user can press "X" to Xecute a runable
pascal file.  This is how TI PILOT is started, for example.
The user can also press "I" to reInitialize the pascal
system if different pascal disks are placed in the active
drives, or press "H" to leave pascal and return to the TI
title screen for normal computer operations.  Prompts for
other parts of the total P-system are displayed, but most
require extra cost software.

    The only way to do any disk or file management is with
the extra cost pascal "filer" software, booted from the
first drive by pressing "F" from the startup menu.  Ordinary
TI disk managers such as DM1000, DSKU, and Funnelweb's DISK
REVIEW do not recognize Pascal files and cannot be used to
print such files or move them from one disk to another.
Pascal files are stored on disk as "blocks" each
corresponding to two regular disk sectors.  To an ordinary
TI disk manager a pascal disk says it contains only one file
(usually named PASCAL) that occupies the whole disk.  An
ordinary TI disk manager must be used to initialize a new
disk for use with UCSD Pascal, but the newly initialized
disk has to be "zero"ed by the pascal filer before pascal
can use the disk.  The pascal filer, once loaded, displays
its own set of prompts at the top of the screen, one of
which is Z(ero).

    The filer's V(olume) command lists all the parts of the
P-system on screen as names and accompanying numbers. 1=
CONSOLE. 2= SYSTEM (the system software in the p-code card's
ROM). 4= name of disk in the first drive (known to most of
us as DSK1). 5= disk name in second drive (aka DSK2). 6=
PRINTER.  7= REMIN (I don't know what this means).  8=
REMOUT (ditto). 9= disk name in third drive (DSK3). 14= OS
(operating system, presumably part of the P-code card). 31=
TAPE.  You use these numbers a lot in file loading, saving,
and management.  To copy a file from the disk in the first
drive to the disk in the third drive press T(ransfer) from
the list of filer prompts.  You are prompted for the file
name and then asked "where".  Typing "#4:,#9:" copies the
file from the first drive to the third drive, which is
device #9.  If you don't know a file name you can display a
disk directory from the filer by pressing either L(ook) or
E(xtended directory).

    The T(ransfer) filer command is also used to print a
file to the printer (#4:,#6:), but there is a potential
problem.  The p-code card expects a printer to be attached
to the RS232/2 port.  (I think it expects a modem at
RS232/1).  Just in case you don't have a serial printer and
the necessary Y cable needed to attach it to the "/2" of the
RS232 port you have to change device #6 to "PIO".  A utility
program that comes with the editor/filer software package
will accomplish this, but you have to run this utility
program every time you boot the p-system.  The RS232/2
designation for printer device #6 is in the p-code card's
ROM and there is apparently no way to permanently change
this.  There is, however, a convenient solution:
    ----------
     THE MARVELOUS LIMA UCSD PASCAL BOOT DISK:

   {This DSSD disk is #705 in the Lima group's software
library.  ANYONE (not just members of the Lima UG) can get
a copy by sending a disk and paid return mailer to the Lima
UG at P.O. Box 647, Venedocia OH 45894}

    Put the disk in drive 1 and turn on the computer.  First
this disk sets the printer device name (device #6) to PIO.
The user is then asked for the current date.  The disk then
boots the filer.  All of this except entering the current
date is done automatically upon system powerup.  The actions
taken by the Lima boot disk make using the TI p-System much
easier and more convenient.
    ----------
     CREATING YOUR OWN PASCAL SOFTWARE:

     You use the pascal editor to do this, which is called
by pressing "E" from the main system menu.  When booted the
editor presents you with a new set of possible prompts.  You
press I(nsert) to begin entering your pascal program.  You
can also use the editor as a text editor to create documents
(similar to using the EA module's editor as a word
processor).  Like TI Writer, the pascal editor gives you
access to an 80 column work area by windowing left/right.
The keypresses that control the pascal editor are, however,
oftwn quite different from those of TI Writer, perhaps
because the pascal editor was originally developed for use
with the 99/4 which has no function key.  On a 99/4A
left/right windowing is controled with FCTN/7 and FCTN/8.
Line delete is FCTN/9.  Once the source code of a program
has been typed into the editor it is saved to disk as a
".TEXT" file.  You then exit the editor and press C(ompile)
from the main Pascal menu to boot the compiler software and
turn the text file into p-code.  The resulting ".CODE" file
can be run at any time from the main pascal menu by pressing
X(ecute) and then specifying the drive number and file name.

    UCSD Pascal is not a common programming language today.
However, type in pascal programs can be found in computer
books and magazines from the 1982-84 time period.  For
example, a rather long type in income tax record keeping
program written in pascal appears in one of the early 1983
issues of BYTE.

     Pascal is a "structured language" whose syntax follows
very precise rules.  Code written by one person is usually
easy to understand by another person who is familiar with
pascal.  This often is not true for BASIC program listings.
Large software applications to be written in UCSD Pascal can
be divided into a number of small segments each assigned to
a different programmer for development.  These separate
pieces of programming code can be individually tested and
then because of the logical syntax of pascal it is
relatively easy to combine the separate pieces into large
blocks of program code.  A pascal source code listing
appears to be written in outline form, with various degrees
of "indentation".  Short independent pieces of code
(indentented the most from the left margin of the listing)
can be combined to form larger units of code (indented less)
which in turn can be combined into larger code units.  The
effect is similar to using Extended Basic subprograms
developed by others in your own programs.  Because of its
"logic" and "structure" pascal is sometimes taught in
introductory university level computer programming classes
as an example of the concept that software written in any
computer language should be logical and understandable by
others (I hope you understood that!).
---------------
     TECHNICAL INFORMATION ABOUT THE P-CODE CARD:

    I have had no problem with text oriented operations of
P-code card software, even using a system with a Horizon
Ramdisk set for CRU address 1000.  Since the p-code card
takes control of the computer BEFORE the CorComp disk
controller, one might think that that the P-code card has a
CRU address of 1000, but I don't know this for sure.  I have
run into a strange problem which I think has to do with my
AVPC card.  With the AVPC card in my system I have no access
to the console's sound chip.  This means no beeps, no music,
and no speech synthesis when running TI PILOT.  The computer
locks up every time sound is expected.  Music and speech
work OK in pascal on my non-AVPC system even though there is
a CRU 1000 ramdisk in this system.  Strange!

    The following information is part of a 1987 article by
Anders Persson of Lund, Sweden.  The complete text is
published in the Feb-March 88 issue of the MANNERS
NEWSLETTER, which is available on loan to members of the
Lima UG.

   "The P-Code card has a total memory capacity of 60
kilobytes.  This memory consists of 12K ROM and 48K Grom.
    "ROM: The ROM memory is located at 4000-5FFF.  5000-5FFF
is paged in two pages, but the lower four kilobytes are
always the same.  The paging is done with CRU bit 1F80.
Resetting the bit to zero gives access to the normal page.
Setting the bit to one switches in the extra page.
    "GROM: The GROM chips contain the files that are located
in unit #14: (OS:).  they also contain various data and
assembly code, which is loaded into RAM when the card is
initialized.  The p-code GROM is accessed just like the
console and module GROM chips, but at different addresses."
    The article then goes on to describe in great detain
workspace addresses and a map of 8K RAM under the p-system.
    ---------------
     CONCLUSION:

    I traded my Thermal Printer (device TP) for my p-Code
card.  I find the p-Code card every bit as useful as my TP
was.  There is very little p-System software.  I don't think
any commercial software for any computer is written in
p-Code any more. As of December 1993 the TI P-Code card was
available for $39.95 from TM Direct Marketing (phone
800-336-9966) and for $25.00 from Cecure Electronics (phone
800-959-9640).  Both prices are plus shipping and both these
dealers accept phone credit card orders.  The Cecure price
is for a "limited time".
 .PL 1