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Full text of "Atari User Group Newsletter June to December 1987 Part 7"

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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 
ATARf or any other commercial organization . Any trademarks 
or company names are used either with permission or as an 
informal way of referring to a product or an oiganlMtion. 

Articles ate written and donated by members, Opinions 
expressed in this publication ate those d the individual author 
and da not necessarily represent or reflect the opinions of this 
group or any other orgatifiation or company. 

Articles appearing in this newsletter may be reproduced 
provided credit ts given to the author and to the HOOKED OH 
ATARI COMFUTER KEYBOARD SOCIETY. 

Subscriptions to this newsletter are available for $20.00 per 
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members to attend general meetings, access I q our public 
domain library, subscription to this newsletter and discounts at 
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 

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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.