CP/M/CPM_CDROM.iso/lambda/soundpot/p/px8dir.lbr/PFDIR.DZC/PFDIR.DOC

Text File | 1993-10-25 | 8.0 KB | 139 lines

        PFDIR, A DIRECTORY PROGRAM FOR USE WITH WORDSTAR
                       AND OTHER SOFTWARE

                           BY: Mr Bob
                            12/24/85


     One of Murphy's Bylaws says,  "The most critical information
required  will be lost or forgotten."  Sometimes I find myself  a
victim  of  that  very  rule,  or at least  it  seems  that  way.
Consider  running WordStar on the Epson Geneva PX-8,  most people
I've talked to,  like the version of WordStar on the PX;  however
most wish that this version offered a directory function like the
desk  top  version does.   Don't get me  wrong,  I  believe  that
Micropro did an outstanding job of making WordStar work with only
32K  of code,  it's just too bad that there wasn't a little extra
room  for a directory function.   However there are solutions  to
the problem.   One solution wrote the directory to the disk as  a
file that could be merged into the current work area.  Once read,
the  directory lines are deleted.   This solution works,  but  is
somewhat klutzy.  Another solution is a patch program that is run
before WordStar.   The patch program loads WordStar in, changes a
few  pointers  within  it,  and  adds the code  for  a  directory
function.   This solution is a much better one, but won't work if
a  user  runs WordStar without going through the  patch  program.
Giver the fact that WordStar isn't the only program that does not
offer  a  directory  function,   a  more  universal  solution  is
required.  PFDIR is the answer to this problem.

     Once PFDIR is loaded and enabled,  seeing a directory of all
your files is as easy as pressing CTRL-PF1.   The nice part about
this  is  the fact that you can see the directory at  almost  any
time without messing up what you've done.   For example,  you can
be  in the middle of typing a command line in  CP/M,  press  PF1,
view the directory,  and return to typing the rest of the command
line without problems.  Also a directory can be seen at any point
while running WordStar.

     The  directory  that's displayed provides  more  information
than the standard DIR command of CP/M.  The standard command just
provides the filenames and their extensions.  PFDIR provides that
and  more.   It also displays the size of the file in K bytes and
the free space remaining in K bytes.   Both pieces of information
are helpful when you are writing a paper in WordStar and your RAM
Disk is running out of space.   The first piece lets you know how
much space a given file requires if you chose to delete said file
in order to free up space for your paper.  The other piece serves
a warning to let you know how much free space is left.

     There  are a few limits to this program;  however  most  are
minor.   First,  the  directory  program can not be run from  the
Password,  Menu, System, Alarm, or Wake Screens.  A trap is built
into the program to prevent the user from crashing the system  by
getting a directory while in any of those screens.   Second,  the
program is placed into the User BIOS Area.   Thus,  the Scheduler
Program  must not be used because it would overwrite the program.
In fact any program that writes into the User BIOS Area can't  be
used.   Scheduler  is  the only program I know of that uses  that
area,  so  this limit may not be too  bad.   Third,  the  program
requires  2  pages  (512 bytes) of User Bios  Area.   This  won't
present  much  of a problem if your system has  an  external  RAM
Disk,  but if your system uses the internal RAM Disk, the 2 pages
of  User  BIOS  Space required,  causes your RAM Disk  to  be  1K
smaller in size.  Therefore a 24K RAM Disk could be only 23K with
PFDIR installed.  Another limit is that this program runs only on
the  new  version of the CP/M Operating System.   The reason  for
this  limit is because in order to perform some of  the  required
functions, direct calls to the OS ROM were required.  While it is
possible  to perform the same direct calls on the old version  of
CP/M, the number of machines that have the old OS ROM aren't that
many  in number and besides,  machines that have the old  version
ROM  should  have  been  (or can still be) upgraded  to  the  new
version ROM.   Last of all, version 1 of PFDIR reads the files on
drive A:  only.   I hope to expand this program later and offer a
directory  of any drive,  but for now the program was kept  small
and  simple.   For those of you who work only from the RAM  Disk,
drive  A:,  this won't be much of a limit.   Others who use the 3
1/2 inch Disk Drive,  will have to wait for an expanded  version.
Both Source and Object code to this program are public domain, so
anyone who would like to take a shot at improving the program are
welcome to do so.

INSTALLING PFDIR:

     Installing PFDIR is easy,  the program has several built  in
tests  to prevent a user from crashing his or her machine due  to
incorrect  setup.   For  example,  the first part of the  program
displays  a  opening message that explains what  the  program  is
designed  to do.   Pressing the red STOP Key or CTRL-C aborts the
program at any time.   Pressing the RETURN Key causes the program
to  continue.   Next  the program tests the OS  ROM  within  your
Geneva  to see if it has the correct version.   If your PX-8  has
the  old  version  OS ROM,  the program warns you that  it  can't
continue running because your system has the old version ROM.  If
your system has the new version ROM,  the programs tells you that
you have the correct version of the OS.

     Next a the program runs a test for a header in the User BIOS
Area.   If  the program finds,  "UB" or "US" in locations  $EBF0-
$EBF1, it assumes that a valid header for User BIOS exists.  (For
additional information on the User BIOS header,  please see pages
17-21 of PX-8 SYSTEM ESSENTIALS.  This technical manual should be
available  from  your Geneva dealer.)  Should  a  correct  header
exist,  the name of the current routine is displayed.  Currently,
I  think this is the only program using this header format,  thus
the  routine name won't be displayed unless you run  the  program
twice.   Pressing  the return key at this point will disable  the
program  within the User BIOS Area (if possible).   Pressing  the
STOP key aborts the program.

     After  that,  the program looks at the size of the User BIOS
Area.  If this area is NOT 2 pages in size, the program warns you
that  it  can't  continue because the User BIOS  Area  isn't  the
correct size.   Should that happen, just run CONFIG to change the
size  of the User BIOS Area to 2 pages.   A few words of  warning
BEFORE changing the size of the User BIOS Area:   If the size  of
the User BIOS Area is 0 pages,  there is nothing stored there and
no  need  to  worry about overwriting anything;  however  if  the
number  is  anything greater than 0,  data or a  program  may  be
stored in this area.   More than likely it's the data is from the
SCHEDULER  Program.   If  you don't care if this data is  erased,
just  exit the CONFIG program and press the RESET button  on  the
left  side  of the Geneva.   Pressing RESET undoes any  hooks  or
changes  that SCHEDULER might have made to upper RAM.   Those  of
you  who have an internal RAM Disk set to 24K,  won't be able  to
select  a User BIOS Size of 2 pages,  until the RAM Disk Size  is
dropped  to 23K.   Before you change the RAM Disk Size,  save all
the  files  you wish to keep to tape (or Disk if you  have  one),
then you can change the RAM Disk Size.

     Once  the  User BIOS Area is 2 pages in  size,  the  program
tells you that it's ready to load itself into the User BIOS Area.
If for some reason you don't want this to happen,  just press the
RED STOP KEY.   If you want the program to be loaded,  just press
RETURN.   Once loaded the program is installed and CTRL-PF1  will
display a directory.