HOOKED OH ATARI COMPUTER KEYBOARD SOCIETY
Volume Tour, number nine
Studium Omnibus Habendum Est
September 1987
Kitts' Cadre
Kitts is looking for volunteers for the
SOUTHERN CALIFORNIA ATARI COMPUTER
FA I RE, VERSION 2,0. He wants more than
warm bodies, fie wants slaves. For more
information call him at 818-848 7336.
Such a Deal?
We have discount tickets for sale for the FA I RE,
You can give us $3,00 now or $5.00 later. I Us
your churse.
^JSroderbund
)ur ST Graphics 5IQ will be honored with an
.xhibition of their fantastic products. Wear your
karate shoes. You will also be able to view their
Director series of software. Remember Print
Shop? Well get ready for the ST version.
Kees' Corps
He has volunteered to man the H.A.C.ft.S.
booth. So if anybody wanting to do volunteer
work and is afraid of Kitts he can talk to kees.
Just in Case
The Dates: 9-19 Sr 9-20
The times: 10 6 6f 10 5
Schedule:
09-0 1 : ST GRAPHICS SIG @ 7:00 PM
09-05: REGULAR MEETING @ 10:30 AM
09-08: ST GENERAL MEETING @ 7:00 PM
09-15: 6502 CLASS @7:00 PM
09-22: MIDI SIG @7:00 PM
The Tuesday meetings are at Logical Choice,
Hall. ..Hall the Gang's
_ All Here
i/e now meet at the log cabin at PACIFIC FARE
n Bur bank. That is one block North of Victory
and three blocks West of Hollywood Way in the
3700 block of Pacific Avenue. Anyone caught
wearing a stove pipe hat will be shot. The rest
of the stuff stays the same. Doors open at
10:00 and the meeting starts promptly at
i 0:04 AM.
Programming
Techniques
by root beers
This column is pretty much dedicated to
explaining some of the general data structures
and techniques for programming.
This month's exciting episode: programming
for speed.
Perhaps you have written a program before
which does what you need It to do but iUs so
slow you might as well take a nap or go to the
store while it runs. How do you make it run
faster? There are lots of ways to speed up a
program, but the best way is to write the
program to run fast from the beginning.
The first thing you should really ask yourself
is "how important is speed of execution"? My
point here is that in general you are either
concerned with how fast you can get good
results at all (how long it takes you to program
and debug it) or you are interested in how fast it
will run without regard to how long it takes to
program it. Most of the time, you care about
both, but think about your speed objective at
the earliest point that you can.
The second thing to think about is the
language you wish to use. BASIC can be fast if
you compile it, but that often means that you
should restrict yourself to integer mathematics.
Assembler is the fastest to run but takes
longest to program. If you know BASIC and
assembler consider using an assembly
subroutine for the longer tasks.
The third thing to consider is the algorithm
you plan to use. A BASIC program with a good
technique will beat even an assembler routine
with a bad technique. Don't be afraid to do
some research, some good algorithms for the
more well-known problems are available just by
looking in the right college bookstores.
The fourth thing you should consider is the
data representation. If you have a choice
between a floating point and an integer
storage, use the integer when you can. I saw
one of my programs run forty percent faster
just by a change of data representation.
Now with all those things in mind, you should
write the program and get it working,
commented, and readable. The first
programming criteria is always whether it
produces the correct output. Comments and
readability are necessary if you want to ask
someone else's advice or in case you decide to
shelve it for a year while you learn more.
Comments and readability are also useful in
debugging. Then when it works, and iUs
already dose to as fast as you can write it, since
you kept the first four rules in mind when you
wrote it, you should make a copy of it and start
to reread and hone it for speed.
Given that you kept these things in mind
when you wrote your program, when you read
through it again to try to make it faster, keep
the following things in mind: (I) EVERYTHING
takes time. Save any calculations you can use
later. Put subroutines in-line whenever possible.
Try to imagine what the language is doing for
(and to) you (for example, reading an array
takes more time than reading a simple
variable). (2) "Ninety percent of the execution
time is spent in ten percent of the code" is a
common addage. Don't bother working on
anything but the routine which is slow. (3)
Remember that the goal is speed, not size. I
have some programs that use half of memory
for one table so that the program can go faster.
(4) Remember that there is ALWAYS another
way to do whatever it is you're doing. Ask
others to look over your work and see if they
can see a better way.
I hope these ideas help, I have a couple
programs that I come back to every other year
or so just to see if i can come up with some new
way to make it run just a little faster. Probably a
silly goal but it's good sometimes to try to one-
up yourself.
The President's
Comer
by John Ring Tarpinian
Well, this is the month. The month of the
FAIRS. I cannot wait for it to start, Then again,
the minute it is over I will have a nervous
breakdown.
As of the writing of this article everything is
going more easily than I had hoped for,
Exhibitors are buying booths and paying ahead
of schedule. All the ACENET clubs are banding
together to make sure that this show is a
success.
We have discount tickets for you. They are
three dollars from the dub. The cost at the door
is five dollars. Such a deal.
As you know by now the Golden Mall Pavilion
is, by now, an intersection. Do not fret we do
have a new home. It is the log cabin at Pacific
Fark, That is one block North of Victory and
three blocks West of Hollywood Way in the 3700
block of Pacific Ave,
BR0DERBUND will be coming to our ST
Graphics SIG this month, September 1st. They
H^OKS
President: John king Tarpinian
[Newsletter Editor: Kitts Anderson
Public Domain Editor: Alan ttagge
Telecommunications Editor: Dave Evans
Contributing Editor: Ross Beers
ST SIG Chairman: Tony Lee
Hidi SIG Leader: Glenn Feit
Graphics SIG: Mike Malloy
8 Bit Librarian: Ron Baxter
16 Bit Librarians: Kevin Gallagher and
Steven Blackburn
Graphics and Layout: lew Marchese
founder: Greg tllscott
founded: June, 1981
This newsletter is published by the HOOKED on atari
COMPUTER KEYBOARD SOCIETY. HACKS, 3n informal
association of individuals. This group is not affiliated wilh
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ATARI COMFUTER KEYBOARD SOCIETY.
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participating retailers-
will be showing us Print Shop ST. karateka, Art
&Pilm Director.
My hand is getting sore. So you get a short
piece from me this month.
Programming
Finesse:
Another View
by A/an tlagge
As rootbeers pointed out in his article
Programming Finesse", the cost of software is
beginning to far overshadow the cost of
hardware, and all signs point to an every-
widening gap, A term often heard Is the
"software life cycle". This refers to the cost of
the software over the entire length of time it is
used, from initial design, through development
and coding, to maintenance and modification
(typically the most expensive part).
It is this life-cycle cost that is skyrocketing
with no end in sight.
Pd like to take a look at the problem from
another angle, one that is just today beginning
to catch on. Many of you may have heard of the
Ada language. Ada was developed for the
military to try to attack the cost problem by
facilitating all aspects of the software life cycle.
A number of new ideas were proposed to try to
make large software projects manageable (by
large. I mean over I million lines of code!!)*
A software design methodology which is
quickly gaining favor in industry, and one
which Ada supports quite well, is the concept of
Object-Oriented Design, or 0OD. The basic
premise of 00D is to create a compilation unit
(in Ada this unit is called a PACKAGE) which
contains a particular object and all of the
operations which may be performed on that
object
For example, take a stack, A stack has two
basic operations, PUSH and POP, In (his case,
the STACK package would contain the object
STACK, and the operations PUSH and POP A
trigonometry package might contain an object
called an ANGLE, with operations of 51N, COS,
TAN, ARCSIN, ARCCOS, and ARCTAN
permissible on the object ANGLE,
Two key advantages that come from this
design approach are low coupling and high
cohesion. Coupling is the degree to which two
routines depend on each other or on common
data shared between both. Cohesion is the
degree to which a routine can stand on its own.
with no outside programs or data except input
and output parameters. Low coupling and high
cohesion make for "stronger" (read more
useful and easily maintainable) routines.
The concept of a package is not necessarily
limited to Ada however. You can take advantage
of this facet of 00D in your programs as well. If
you write in Fiscal or C, you can create
subroutine files which can either be included or
better yet, linked into your main code. The
guidelines for these packages are:
1 ) Put only one type, or a group of related
types into a package. If a new type (Le,,
enumeration or record) cannot be used,
document which type of variable (Le.,
INTEGER, REAL, etc.) is to be used with
this package,
2) Think of all possible operations you might
want to do on those types, and implement
them as subroutines and functions within
the package,
3 If at all possible, DO NOT use any external
variables except those which are passed as
parameters,
4) Try to minimize the use of routines not in
the package. If you MUST use routines in
another package, document that fact at
the top of the package, since any changes
to the other package might well affect this
one, too.
5) By all means, use meaningful variable and
function names! XI . Y2 and P are
worthless names when you have to look at
year-old code.
There are other aspects of Ada and OOD
which I think you will find helpful in your
coding practices, whichever language you
choose. Next time, 111 take about the concept
of reusability and the Ada generic pro
gram unit*
YOUR
ARTICLE
BELONGS
HERE.
A ATARI ST, XL &XE
DEALING
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Something to Do
by rootbeers
This column is dedicated to presenting some of
the 'classic' and/or bizarre programs and
problems of computing in the hopes of
encouraging others to try their hand at
programming.
One well-known computing diversion is called
"life". Take a piece of graph paper and fill in a
few squares. This is called a "Generation" and
since you just created it out of thin air, let's call
it generation O. Each filled in box is a "Marker"
and the number of markers is the
"Population", Each marker can have as many
as eight "neighbors", which are the squares
above, below, left, right and diagonal, how take
a second sheet of graph paper and fill it in
accordance to the following rules: if the
corresponding box on the first sheet of paper
has exactly three neighbors, then fill it in. if the
corresponding box on the first sheet has two
neighbors then fill it in only if it was filled in on
4
the first sheet. Do this for all squares of the
graph paper, and you have created generation
1. See generations 0 through 4 for examples.
Pretty tedious, huh? Well, that's where the
computer comes in. The goal is three-fold: do
the necessary calculations, do as large an area
as possible, and do it as fast as you can.
Mow someone is going to ask "why do it at
all?" and the answer is really the name of the
column, but to be honest, the patterns which
emerge from the simple rules are truly
incredible. Tor instance, there are "gliders"
which move across the graph paper. There is
even a "glider gun" which sends off a new
glider every sixty-some-odd generations.
I have not yet seen what happens when one
uses similar but different rules or even different
shapes. The possibilities are enormous and it is
a good application for a graphics -oriented
machine. One thing I have become interested in
is the possibility of creating a set of rules for a
three dimensional life.
Anyway, ask around and I'm sure you'll find
someone's home-brewed version of life to play
with. If you can't though, try your hand at
writing it yourself. You've got nothing to lose
but your piece of mind, your self-respect, and a
few night's sleep. When you've lost all that,
you'll fit right in with the other hackers.
flCENET
ATARI
COMPUTER
ENTHUSIASTS
NETWORK
CHARTER MEMBER
-ST MIDI SIG
Ben Di Tosti
The 3rd H, A.CK.S, ST-MIDI SIQ meeting which
occurred the last Tuesday of June had been
expecting to see a demo of the STEINBERG Pro-
24 sequencer. Due to the fact that the National
Assoc, of Music Merchants (NAMM) show was
scheduled that weekend, the people who
represent STEINBERG decided to leave earlier
for Chicago and therefore cancelled their
appearance. By the time you read this, they
should have done their presentation at the
August meeting. The meeting was certainly not
a washout because we again had the
opportunity to benefit from the wealth of
experience that meeting moderator Glen Feit
brings to these MIDI gatherings.
The 4th ST-MIDI SIG meeting took place the
last Tuesday of July, at LOGICAL CHOICE FOR
COMPUTING, A brief recap on the above NAMM
show occurred, and it seems that a complete
floor was dedicated to music software. The
approximate count of computers was as
follows: IBM-21; MAC-20; Atari 5T-55;
Others— 5. Atari made headlines as the first
personal computer company ever to sponsor an
exhibit at NAMM, The highlight of the show, it
seems, was the introduction of the ALE5I5
drum machine, HR 16. Features include 48
various drum sounds of the past 50 years that
jh be stored as 100 patterns and 1 00 songs.
r ery sound is tuneable, touch sensitive, and
assignable to any pad, MIDI is implimented. Are
you ready for the price? $4491 But you gotta
wait til the late fall {early next year?) to
purchase it.
Other companies displaying their MIDI
softwares were AEGIS, AKA3, BEAM TEAM,
COMFU MATES, DIGIDESIGN, DR. T.
ELECTRONIC ARTS, HYBRID ARTS, MOTRON,
PASSPORT, STEINBERG, and TWISTER. For an in
depth report of the above consult the August
issue of ST Applications,
After the rap on NAMM, we were given a
rather lengthy demo on some of the new
updates which will be released this fall by
HYBRID ARTS, in particular, 5MPTE track.
Programmer Stephan Daystrom, who
incidentally has attended all of our MIDI
meetings, proceeded to describe those features
he has been crafting of late, of which the major
one is the graphic editor. This consists of a split
screen showing a selectable range of notes— in
time— on an horizontal axis, together with a
four octave vertical display. The upper right
screen area consists of Individual highlighted
information correlating to whichever note the
mouse is pointing to on the grid, such as note-
name, start & stop time, attack and release
velocity etc. Clicking on a note selects it for
Siting in which the aforementioned values may
be altered.
Additionally, you may grab a whole range of
notes with the mouse and then zoom in and
play, transpose, or delete that particular
section, Stephan claims that the user will also
be able to "paint" a range dynamically to affect
crescendos and diminuendos, as well as redraw
other controller effects such as pitch-bend,
after-touch and MIDI volume.
Other additions are a fast forward/rewind
screen button similar to that of tape machines,
and localized track editing features which
include quantizing, transposition, and velocity
editing.
Also planned for the fall release is a rather
useful feature that will allow the user to
establish and change time signatures
throughout the track layout. Stephan claims
that measures, beats and ticks will now be
displayed.
Shadow Track allows you to copy a track to
another track in order to permit it to be set to a
different MIDI channel (thus a different layered
patch-sound) or a different track delay. Another
advantage is that the user can assign a looping
structure to two locations. And all this is done
on a temporary basis so that there is no need
for additional memory.
Another new feature will allow the user to
record system-exclusive messages within the
sequence. This would allow forshorlt messages
to aid in future MIDI spec extensions such as
would allow for larger patch-bank changes.
Next, Stephan elaborated on Gen Patch SI
which Is a powerful stand alone program that
can handle a complete MIDI patch library and
works with any MIDI device: synths, drum
machines, effect units, and samplers. It has a
configuration library which is constantly
expanding and is available for download off the
HYBRID ARTS BBS, It also has a built-in
configuration editor to allow the user to form
new configuration files for any MIDI instrument,
including future products. The reai-time MIDI
data display screen is quite instructive In
showing the actual code that occurs when you
play a note or send a patch dump.
Finally, there is the GenPatch Desk Accessory,
which is a part of SM PTE -Track and SYNC -Track
and loads various synth patches from within
the sequencer. Therefore, when you load a new
song the GenPatch File Auto-injector will also
load the proper configured patch for that song
and designate which synthesizer modules will
be active.
One comment on the MIDI meeting. It seems
that there is a good mixture of apprentices and
seasoned MIDI users. However, I can't help but
notice the continued perplexed looks of some
who probably feel they are in over their head. I
can only say that MIDI is BIG and growing all
the time. Please learn to be a part of it. Do your
homework by reading the few good books on
MIDI as well as the many magazine articles. Do
not be afraid to ask questions. Also remember,
you learn by doing! Do buy an inexpensive
synth and moderately priced 5T sequencer, if
you haven't done so yet. One thing will lead to
another and before you know it, you'll be a part
of this wonderful I new technology.
Ramdisks Continued
by Bees Jongsma
A ramdisk is a portion of ram memory set aside
to be used as a disk storage area. It provides a
super fast access time and easy file
manipulation. In the June issue of Hacks I
covered the Ramdisk programs available in our
HACKS FUBLIC DOMAIN LIBRARY and
described how to use them. In preparing that
article I put together a disk called Ramdisk
Organizer that essentially provided for auto
setup of ramdisks and documentation for their
use. This disk may not yet be in the HACKS
PUBLIC DOMAIN LIBRARY and if not I will be
happy to provide it to those interested. If you
haven't tried working with a ramdisk I highly
recommend that you do as they are very useful.
One of the questions that I received
concerning ramdisks is "Why so many different
kinds?". Each of the ramdisks have slightly
different features. These features range from
how they boot to size limitations and
resetability. Some of the ramdisks will not work
with certain software (watch out degas users)
and it is recommended that you try out a piece
of software before using it for a serious
application.
I recently found a great application for
ramdisks and MAGIC SAC. Since I have a single
drive 5T with a MEG of memory, booting up a
large Macintosh application required the
swapping of the systems disk and the
applications disk a number of times. This is a
real drawback for serious users (such as myself)
and I knew that if a ramdisk could be made to
look like the boot disk that my problem would
be solved. I hooked up to Genie and found that
my problem had already been solved with the
use of a program called RAMSTART.
By inserting this program into the system
folder it can be made to auto boot and dump
the rest of the system folder into the ramdisk, I
am using Ramstart version i ,2 and version 1 .3
should also work. I recommend the following
procedure to set up your MAGIC SAC ramstart
disk,
1 . Prepare a new magic sac formatted disk
2. Copy system folder onto the disk including
ramstart in the system folder
3. Open the system folder and dick on
Ramstart once
4. Go to the menu bar and select "set
startup" from the specials menu
5. After the disk is done spinning you are
done.
At this point you reboot the system and use
your new Ramstart disk as the startup Disk. As
mentioned above this ramstart may not work
with all application (although 1 haven't found
any that do not work yet) so be careful before
any "real work".
Norm's Super Duper
All-in-One Floppy
System
Are you ready to add another floppy drive to
your 5T? Handy with tools? If you are
adventurous you might want to try and save
some money by building your own floppy
system.
Recently I decided to upgrade from single-
sided drives to double-sided For my 5205T.
Since i don't have a built-in drive, l figured that
I could build two, external double-sided drives
into one case. 1 purchased two 3,5" drive
mechanisms and a standard case with power
supply designed for a fuill height 5.25" floppy
drive. These cases are cheap and widely
available.
Fortunately two 3.5" drives stacked, one on
top of the other, are exactly the height of one
5.25" drive. So they fit nicely into the case. The
power supply that is built into the case provides
5 volts and 1 2 volts, both at better than l amp.
This is enough power for two and maybe three
3.5" drives. After they are mounted in the case,
there is about one inch on either side of the
drives that is open and unused. I just filled this
with something decorative.
The steps of this project are to physically
mount the drives m the case, to connect the
power lines and the signal lines and finally, to
make a cable to connect the drives to the ST.
The advantage of packaging your floppies this
way is that you ony have one box with one AC
line cable and one signal cable going to the
computer.
MOUNTING
Mounting the drives in the box takes a little
thought. The drives are rectangular boxes, the
connectors facing one end and the front bezel
on the opposite end. The bezel is the painted
part with the slot to insert disks. It should
protrude beyond the front of the case. Or
"they" should, since the drives are one above
the other. I placed one drive on the floor on the
case, with the bezel hanging over the front.
There is an inch left over to either side and
several inches behind.
You could drill holes in the floor of the case to
fasten the drive down, but I found it better to
fashion some L-shaped brackets that fasten to
the floor, in that spare one inch to the sides.
These brackets are tall enough to reach about a
half-inch above the bottom drive. The height
really depends upon where the mounting holes
are placed on the drives you obtain.
There are several threaded mounting holes on
the sides on the drives. I drilled holes in the
brackets in line with these holes. Then, at a
measured distance above these holes, l drilled a
second set. Now the second drive can be lined
up with these upper holes and zip! They're
mounted.
The mounting holes require METRIC screws
(3 mm)! You can force 4-40's into the threads,
but that's crude. The electronic parts stores I
frequent do have little sacks of 3mm hardware
(from General Cement) which contain many
more than you need.
Signals
It is far easier to find 15-pin "D" connectors
than the DIN 14-pin connectors that Atari uses
for the disk drives. Therefore, I mounted a 15-
pin "D" female to the back pane! of the case. I
then took a one foot piece of 34 conductor
ribbon cable and mounted two 54-pin
insulation displacement connectors, one at an
end and the other about 2 inches from the first.
They are going to plug onto the drives, so place
them so you can get them both connected
comfortably.
At the other end of the ribbon cable, the
individual wires are separated. The ones that
will be connected are stripped and tinned, the
others are cut off. See Table I.
More Signals
Looking at the printed circuit board of the
floppy drive, in the vicinity of the 34-pin
connector you will find two rows of vertical pins
with a little, plastic bodied rectangle plugged
across one pair. Letting on the board will
indentify the pins as "D50, D51", etc. Usually
this shorting-plug is connecting the D50 pins
(Drive Select 0). In this position, the drive will
respond as drive "A". Pull off the plug on one
drive and plug it onto the pins marked "DSl".
This drive will respond as drive "B". Which
drive is "A" and which is "B" is your choice.
Now look at the components near the 34= pin
connector carefully. One DIF (dual in-line
package) or SIP (single in-line) is not soldered to
the board, but is socketed. The printing on the
board near it may say "Terminators". These are
the pull-up resistors of the signal lines. They
serve a very specific purpose and must be
connected only at the connector which is at the
end of the line. That's the reason they're
socketed. When the ribbon cable is in position,
one drive Is at the end. Leave the resistor pack
in
that drive, but remove it from the other drive.
Ribbon
Wire
TABLE i
15-Pin
Socket
Signal Name
8
4
Index Pulse
10
5
Drive 0 Select (Drive A)
12
6
Drive 1 Select {Drive B)
16
8
Motor On
18
9
Direction In
20
10
Step
22
11
Write Data
24
12
Write Gate
26
13
Track 00
28
14
Write Protect
30
1
Read Data
32
2
Side Select
Odd*
3,7
Grounds
15
Net used
* All odd numbered wires of the ribbon cable
are connected to ground. Choose two
convenient ones to wire to pins 3 and 7.
The cable from the ST to this system is made '
from a standard Atari floppy cable or an
equivalent extension cable. Cut off one of the
fourteen pin DIN connectors and mount a 15-
pin connector at that end. Except for pin 15,
which is not used, each pin is connected one-
to-one to the same numbered pin.
Power
There is a three wire cable from the power
supply. One wire is ground (almost certainly,
the black one), one is -f 5 volts and the other
+ 1 2 volts. Use a meter to find out which. These
terminate in a 3-pin Molex connector. Cut it off
and discard. The power for the floppy drives
connects through a four pin connection on 0. 1
inch centers, i could not find the exact
matching piece in the electronics stores, so I
got some similar ones. They had ridges on one
side for polarization which prevented them from
pushing on the drive, five seconds with a knife
whittled them off and they were no longer a
problem.
The power connection at the drive consists of
four wires. The center two are ground; one
outside pin is 5 volts, the other is 1 2 volts.
Looking at the pins with the drive connector at
the top, the pin at the right end is 5 volts. The
sure way is to use an ohm-meter and check for
continuity to the power pin on one of the ICs,
That'll tell you which is +5V, the other end is
+ 12V. _
You have to make up two power connectors,
one for each drive. Tie the grounds (four wires)
together and splice to the ground wire from the
power supply. Similarly, tie the two + 5V wires
and splice to the power supply; and again with
the + 12V wires.
Done
That's it. You're ready to fire it up[ This project
has been tried and it works. Go to it!
Norm Weinress
6
Cut and Paste
y Steve Blackburn
Newspapers, magazines, and just about
everyone else has used the cut and paste
method of page layout to create the different
types of junk mail that we all receive daily. They
take pictures, text, and graphics that they have
created from various sources and physically
paste them up on the pages that will eventually
sent to the printers. Many if not most still do it
this way. Computer generated pages are not yet
common day occurences.
With programs like printmaster, Degas Elite,
and others combined with your favorite word
processor, it is very easy for you to do the same
thing,
Starting with a blank page, you design it with
the tools you have available. Degas and
Printmaster are great for making letterheads
and logos. These programs are also well suited
for making graphics that can be placed within
your text. By a simple process of cutting out
the images and pasting them to the blank
pages, along with text, you can createjn
almost endless variety of finished proSjcts that
can be used for your own personal useror
created for small companies for a profit. Some
word processors do not have the ability to
create double columns, but by printing out your
^documents at 20-30 words wide and then
asting them up, you can achieve the same end
*sult Graphics and lines from drawing
rograms can be added as well. One way to
achieve a higher quality graphic image is to
create it on a large scale (full page) and then
taking it to your local copy shop and having it
reduced. You can even improve the image by
first taking a tack marking pen and darkening
the areas you think might not reproduce well,
and as we all know, printers are notorious for
leaving white lines in the printout. Once all your
corrections and improvements are made, have
ft reduced to the size needed and then paste it
up with the text you have created. Once all of
this is on one piece of paper, take some white-
out material and go over the areas of the paper
that might cause problems (the edges of the
individual pasteups are your biggest problems),
Now take it down to the local print shop and
have them make you one copy. Use whiteout for
any other areas that are causing you problems,
and then have them run off as many copies as
needed,
I have had a lot of fun doing things this way,
and have created pages that would compare to
many or the commercially available methods of
creating flyers, ads, etc. Your imagination and
design skills are all that are keeping you from
creating truly professional finished products.
I enjoy graphics and creating printed copy,
^and anyone else who is interested in the same is
r e!comed to ieave me messages on the 5T
UNGLE m3 (213) 254-9534 (leave messages
ior Steve Blackburn or The Bear on the
graphics/program help base).
hope to be hearing from you...
PD Spotlight
by Alan tiagge
I'm back! Now that Tm lost in the desert. I'll
probably only be able to get out an article every
other month or so. Bear with me, and if you
can't stand it, write one yourself!
This month Td like to tell you about a home
loan calculation program called Home Loan
Analysis, It was written by J. f. Skinner for
Antic Magazine and available on the Finance l
disk in the library. This program allows you to
do "what if?" calculations on a home loan,
such as "how mucitless will my payments be if
I put 20% down rather than $5000.00?" Or
"how much interest can I save by taking out a
15 year loan rather than a 30 year loan?"
An easy To- use main menu prompts you for
such variables as the purchase price of the
house, the down payment, the interest rate,
and the length of the loan. The program has
enough smarts to calculate some variables
based on those you give it. You can then easily
change any number and have the computer
calculate the changes. As an added feature, the
program can compute the future value of your
property, based on the buying price and an
appreciation rate.
The most important part of the program
allows you to see an amortization of your loan.
You can look at the whole thing or any year
within. It also shows the cumulative totals of
principal and interest for each year. All of the
information can also be sent to your printer.
Granted, there are other public-domain loan
programs out there, and most do pretty much
the same thing, but I found the Home Loan
Analysis program to be the easiest to use. My
sole gripe is that It will sometimes recalculate
the wrong variables in the loan formula ("I
wanted my payments to do down, not the
purchase price to go up!!!"). But all In all a
useful program for anyone looking into real
estate.
The Mouse & the
Handicapped
by John King Tar pint an
Now that 3 have lost the use of an arm, for the
next six months, I have learned to appreciate
my mouse & even GEM. Just try Control/
Alternate/ Delete on an IBM using one hand,
You need to put a pencil between your teeth to
do It, A single click of the mouse button can
usually take care of most operations.
Even with a word processor, the GEM and the
pull down menus make typing relatively easy, l
am a touch typist. I have had to learn to type all
over again. I use the eraser end of a pencil as a
typing helper. The pencil allows me to reach
across the keyboard more quickly.
Of course using a joystick is a problem. But,
games such as BARBARIAN are fully mouse
controlled with no keyboard input needed
either. Eorget about Flight Simulator EE. Of
course I cannot play that with three hands.
This is just something I have become aware
of that I never thought of before. We take so
many things for granted. Those of us that have
the use of all our limbs should be grateful and
more considerate of those that do not.
Speaking Like a Pro
by root beers
In this column ! attempt to present some of the
actual jargon I've actually heard used by actual
computer programmers. Generally a bit on the
silly side, but after all, fun is why we're here,
Pel— This is IBM-ese (,JBM-ese; kind of
sounds like a laxative, doesn't It?,..) for pixel,
which is the smallest picture unit which can be
addressed or altered.
Set— a coallection of things which has no
order associated with it but has the property of
"uniqueness". That is, an Item is either in the
set or not in the set but there are no duplicates.
Bag— a bag is the same as a set except that it
may have duplicates.
Sequencer sequence is a collection of
things which have an associated order.
Confused— a euphamism for "wrong"
usually used in referring to inaccurate
statements made by one's superiors.
Sleeper Hold— The mechanism by which one
program during the course of Its failing causes
"normal" programs or files or hardware to fail,
Vent one's spleen— a rather graphic phrase
connoting getting something off your chest.
Note the rather Picasso- istic change of
anatomy.
Line of Death— The highest address of usable
memory. Sometimes used to mean simply the
end of available memory.
Oxymoron— The guy who "does" fries at a
fast food place.
