                     P E R I O D I C
                     ===============

A  program  to display the periodic table and information
about the elements for the Psion 3a. Version 1.414...

(c) Anthony Kucernak, February 1995.
[ark1000@cus.cam.ac.uk]

This  software is provided free of charge  on  the  basis
that  it  may only be distributed provided that  this  is
done  for free. Any distribution must include all of  the
files listed below in their original form.

Filename       Size
Periodic.opa   11652
Periodic.dbf   23580
Periodic.pic   9620
Periodic.txt   10328

                       WHAT'S NEW
                       ==========
The following changes have been made to this version of
Periodic:

      o Improved display of information on the
         elements.
      o Better editing within the section devoted to
         molecular weight calculation
      o Changes to the information on some of the
         elements.
      o A bug which stopped the program running off
         some SSDs has been fixed.
      
                      INSTALLATION
                      ============
NOTE:
This  installation  procedure differs from  the  previous
version of this program. The data files are now stored in
a  subdirectory  of  the APP directory  in  keeping  with
common practices.

The OPA for this software, PERIODIC.OPA, should be copied
into  the  \APP\  directory of any drive. A  subdirectory
should   be  created  in  this  \APP\  directory   called
PERIODIC,   i.e.   \APP\PERIODIC\.  The  database   file,
PERIODIC.DBF, should then be copied into this  directory.
If  you wish the program to start up quickly then you can
also  copy the screen image file, PERIODIC.PIC, into this
directory as well. If you are short of space then you can
omit  this  file.  It can be re-created from  within  the
program at any time.

The information relating to where the files are stored is
summarised below.

\APP\
     periodic.opa
\APP\PERIODIC\
              periodic.dbf
              periodic.pic    (optional)

The OPA file should be installed from the main screen  as
for other applications (using psion-I).

                        START UP
                        ========
On start-up the program should display the periodic table
followed by an information screen detailing creation date
etc. The program requires cA. 34K of memory to run.

                   FINDING AN ELEMENT
                   ==================
Elements may be selected either by using the cursor  keys
or typing the symbol for that element.

Using Cursor Keys
~~~~~~~~~~~~~~~~~
The  up/down/left/right arrow keys changes the  currently
selected element; similarly, pressing the PSION-key along
with  one  of  the arrow keys moves to the  edge  of  the
table. If an element remains selected for more than about
one   second,  then  information  for  that  element   is
displayed in a window.

Typing the symbol for an element
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
By  typing the characters that make up an elements symbol
(e.g.  Ru for ruthenium) it is possible to directly  jump
to  an  element.  As there are a number of elements which
have as there symbol only one letter (e.g. O, oxygen;  F,
fluorine), you must be fairly quick about typing  in  the
two  characters otherwise the cursor will lock  onto  the
element  which  has  as its symbol the  single  character
which  you have typed. For instance, If you wish to  jump
to iron (Fe) and press F, but wait a little too long, the
cursor  will  remain  on  F and display  information  for
fluorine.  If this happens you must start again.  If  you
type  a  wrong character, press ESCAPE or SPACE to cancel
the  character typed. Once you have found the element you
want,  information on that element will be  displayed  in
the  window  above the table.  Accessing  information  in
this window is described in the following section.

         DISPLAYING INFORMATION ABOUT AN ELEMENT
         =======================================
Once an element has been selected, information about that
element  will be displayed in a window above the periodic
table.  By  default  the information displayed  is  about
radioactive  isotopes. Information about the  element  is
stored  as  a  scrollable list. Pressing the DIAMOND  key
will  select  the next item, pressing SHIFT-DIAMOND  will
select  the previous item (SHIFT-right arrow, and  SHIFT-
left  arrow may also be used). The current selection type
will  lock so that you can move across the periodic table
and  compare the selected characteristic across different
elements.

                       MENU ITEMS
                       ==========
The different menu items are accessed by pressing the
menu key. There are two pull down menus. The first is
COMPOUND, and at the moment only contains one component:
MOLECULAR WEIGHT, this item is further discussed below.
The second menu is labelled SPECIAL and contains three
items: VERSION, SAVE IMAGE, and EXIT. VERSION shows the
startup screen produced on entering the program, SAVE
IMAGE is discussed below, and EXIT is obvious. Each of
these items may be accessed without going through the
menu system by pressing the Psion key and a letter at the
same time. The mappings for these are given below:
          Key                 Menu Item
          ~~~                 ~~~~~~~~~
          Psion-M             Molecular Weight
          Psion-V             Version
          Psion-I             Save Image
          Psion-X             Exit

MOLECULAR WEIGHTS
~~~~~~~~~~~~~~~~~
This  program  will  determine the molecular  weights  of
compounds  typed  in.   This  option  is  invoked  either
through invoking the menu system or pressing Psion-M.
When entering molecular formulae you should type them  in
the  same  way  as  you write them.  The following  notes
should be observed:
     -You  must  type  the characters as they  appear  in
       the   periodic  table.  i.e.  you  must  type  the
       correct  case of the letters. e.g. Fe and  not  FE
       or fe for iron
     -Numbers  always  follow what they  refer  to.  e.g.
       K2PtCl6
     -You   may  use  brackets  (all  of  ({[<>]})  )  to
       include sub-units e.g. Fe3(CN)6
     -Fractional   stoichiometries   are   allowed   e.g.
       WO3.33
The  cursor keys may be used to move through the  formula
to  edit  it.  The delete key may be used to  delete  the
character to the left of the cursor. Psion-left arrow and
Psion-right arrow move to the beginning and  end  of  the
formula;  Psion-Delete  clears the  entire  formula;  ESC
exits  the  formula  calculator;  ENTER  calculates   the
molecular weight for the current formula.

FAST START-UP (SAVE-IMAGE)
~~~~~~~~~~~~~~~~~~~~~~~~~~
On  start-up  the  program checks to  see  if   the  file
'periodic.pic'  exists  in the \APP\PERIODIC\  directory,
and  if  it  does,  it  uses it to  quickly  display  the
periodic  table.  If it does not find this file  then  it
generates  the  image of the periodic table  (this  takes
slightly longer).  It is possible to save this image  for
fast start-up by using PSION-I (save image).

                      THE DATABASE
                      ============
The  information for the periodic table is stored in a  a
database  (periodic.dbf) in the \APP\PERIODIC\ directory.
To  my  knowledge  the information is  correct,  although
there may be some mistakes.  You can update or change the
database by using the standard database application.  The
fourth  field  containing the atomic  weight  information
should  not  be  moved as the program will complain  (the
molecular weight routine assumes that the atomic  weights
occur in the fourth field of the database).
The  program will accept up to 20 fields in the database.
I  have filled in 17. Units for items in the database are
assumed to be bracketed and stored with the field  labels
e.g.  if  you look at the field labels you will see  that
the fourth field is:
     Atomic weight(g/mol)
The  program splits out the (g/mol) and places  it  after
the units when it displays them.
If you find any errors/holes in the database please email
me with the correct data so that I can correct it for the
next release.

                     TROUBLESHOOTING
                     ===============
Problem:      Program   issues  an  alert   "Can't   find
       periodic.dbf" on startup and then shuts down.
Cause: On  startup  the program cannot find the  database
       file,     PERIODIC.DBF,    in    the     directory
       \APP\PERIODIC\ on any drive.
Solution:    Make a directory called PERIODIC in the \APP
       directory  of  any drive and copy the PERIODIC.DBF
       file into it.

Problem:     Program  issues an alert "The Atomic  weight
       field  must  be the fourth field in the  database"
       on  startup.  The program continues but  will  not
       correctly calculate molecular masses.
Cause: Due  to  a  limitation in the program, the  atomic
       weight  mass  must be the fourth  field  and  must
       contain "(g/mol)" in the label field.
Solution:    Reload the PERIODIC.DBF or undo any  changes
       that have affected the atomic weight field in  the
       database

                       KNOWN BUGS
                       ==========
Currently  the  radioactive isotope information  for  the
elements  Ca,  Au,  Bi, U, Pu, Cm exceeds  the  available
space for printing this information.

                    ACKNOWLEDGEMENTS
                    ================

I  would like to thank those people who pointed out minor
problems  with  the program. I would also like  to  thank
Alan  Roberts  for pointing out a critical  bug  in  this
program and offering a solution.

              DONATIONS, BUGS, SUGGESTIONS
              ============================
If the program is of real use to you, then I suggest that
you donate the equivalent of ten pounds sterling ($US 15)
to  Amnesty International. I would be interested to  hear
about any suggestions for improvements to the program  as
well as any bugs which you may find.

My address:    ark1000@cus.cam.ac.uk
          Anthony Kucernak
