Ahoy! Magazine December 1986 - Commodore Computers

THE
ARTIST
FOR THE 128

m
la.
re.
S
extla
ion,
'eval
iI's
lasks.
DEPARTMENTS
FEATURES
PROGRAMS
Cove, Cover art art by J.......... James Regan and _ JOII. Josie 'H lee
•
A View from the Brielge...ofthe Bridge ... of the December issue of Ahoy! Ahoy! 7
Scunlebutt... ScuHlebuH ... what's coming for your Commodore in the New Year. 8
Reviews.. Reviews ... .dashing dashing through the latest latest software and firmware. 60
Art Gallery.. Gallery ... .our our readers decorate decorate this holiday holiday issue. 90
Tips Ahoy!. Ahoy I. .. take a few from your fellow f ellow reader/programmers. 105
Commodares... Commodares ... tough enough to ruin any Christmas morning. 109
Flotsam... Flotsam ... our readers have the near-last word. 115
Program Listings.. Listings .. .stuff . stuff stockings with with our our games and and lIIilities. utilities. 117
Rupert Report: File Manipulator by Dale Rupen* Rupert* 20
Commodore Roots: Roots: The Shadow Knows, Part II by Mark Mark Andrews**27
Andrews**27
Entertainment Software Section (contents on page 41) 41
Cadet's Column: Christmas Presents Present. for Your Commdore 100
Build a Five Volt Peripheral Power Supply by Monon Morton Kevelson 92
*lncludes *lnc1udes programs: Planetary Moons Database and File Manipulator
(for the the C-128)
**lncludes **lnc1udes program: program : SPRlTE2 SPRlTE2 (for the C-128)
The Artist for the C-12B C-128 by by Denoy DeBoer 34
Minotaur Maze for the C-64 C-64 by by Cleveland Cleveland M. Blakemore 52
Mouse in the House by by James C. Hilty 55
The Editor for for the the C-64 C-64 by by Buck Buck Childress Childress 56
Micro City for the C-64 by by Darryl Darryl Hawkins Ha wkins 76
Speedway for the C-64 by Tony Brantner Branlller 78
Lazy Source Code for the C-64 by Michael Bennett Bennell 88
Rebels and Lords for for the C-64 C-64 by Terry Bryner Bryner 96
Bug Repellents for the C-64 and C-128 C-12B by Kleinen Kleinert & Barron 118
Flankspeed for the C-64 by Gordon F. Wheat 119

PUt on your black belt and challenge your
friends or the computer through nine
plcturf9que settings In this leadIng Martial
Arts Game to become the KARATE
CHAMP. For the Commodore 64"'/ 128
and the 48K Apple II 0- Series.
As the crack shot COMMANDO: battle
overwhelming odds to defeat advancing
rebel forces. Armed with only a machine
gun and hand grenades. you must break
through the enemy lines to reach the fortress
. For the Commodore 64''''t 28.
Prepare for the light of your life • •• you
are the KUNG·FU MASTER:" Battle the
evil forces through the flve dangerous
floon In the wizard's castle to rescue the
captive fair malden. For the Commodore
64'"11 28 and the 48K Apple II" Series.

By Dale Rupi--;:"'
hat? You have never used reltive
ftles? fIles? Rumor is that it
takes some sort of programming
genius to be be
able able to use them. Perhaps a high high IQ is a prerequisiterequisite
for learning about relative files from
the original VlC-1541 V!C-1541 Disk Disk User's Manual, Manual,
but as we shall see, creating and manipulating
relative files fIles in BASIC 7.0 is quite
straightforward, ifnot downright child's play.
So what are these relative files with their
strange accompaniment of "side sectors,"
"pointers," and and "records"? A relative ftle fIle is a type
of disk ftle fIle which allows easy, random-order access
to each of the elements in the file. The elements in the
ftle fIle are called "records." To identify which record you
wish to access, you simply set a pointer to that record.
The computer automatically finds the location of the selected
record on the disk and allows you to read it or
write to it. We won't worry about "side sectors" because
it is not necessary to know anything about them in order
to use relative files. files .
There is one more concept we must discuss. Each record
in the file may be further subdivided into portions
called "fields." Locating a specific field within a given
record in a named ftle fue on a disk is really not a difficult
programming task, especially with the model programs
20 20 AHOYl AHOY!
we will create this month.
Our discussion aod and programs this this month
are for BASIC 7.0 on the C-128. The concepts are
identical, however, for BASIC 2.0 on the C-64 and for
other versions of BASIC. After studying srudying the examples in
this article, you should be able to translate the BASIC 7.0
command sequences into your your own computer's language.
RILATIV. RILA TIVI DI...R.NC.S
DIFFIRINCES
Both relative ftles fIles and sequential ftles fues provide structuresrures
in which data data may be stored and accessed. Relative
files are called random access files fIles in other computer

language language dialects. The The tenn "relative" "relative" obscures obscures their their priprimarymary distinguishing distinguishing characteristic: that that each record record is is
individually individually and independently accessible. "Random access"
is a more more descriptive descriptive tenn tenn than than "relative" for for these
files, although although we we are not not dealing with with true random random files files
as defined defmed by by Commodore. Commodore. (See the the March 1984 issue
of Ahoy! for a discussion of random files.) flIes .)
Sequential flies files also consist of records. Before reading
the 30th 30th record in a sequential sequential file, the computer
program program must must first read through through the preceding preceding 29 recordsords
in the file. ftle. This This is the main disadvantage of sequentialtial
files. files. If records records must must be accessed in in random random order,
JOSIE VEE
typically the the program first first reads reads them from from the disk into into
arrays arrays in in memory. memory. Once Once in memory, each each record record is localocatedted by by an index of of the array.
Each record in in a relative relative file file also has has an an index index associaassociatedted with with it. it. The index index is stored stored right on on the the disk disk with
the the flIe file as as it is created. (The (The storage storage areas for for these these indexesdexes
are the side sectors mentioned earlier. The computer
takes care of all this for us.)
Ifeach If each relative relative file file carries carries along along its its own own indexes, indexes, and and
if each record is easily accessed in random order, then
why are sequential flies ftIes even used? The disadvantage
of relative relative files files is is that that they they generally generally require require more more disk disk
AHOYt AHOYI 21

I. Open the file (DOPEN)
2. Point to the desired record(s) (RECORD)
3. 3. Read Read or or write write the record(s) record(s) (INPUT#, (INPUTH. PRINT#) PRINT#)
4. 4. Close the fLle me (DCLOSE) (DC LOSE)
ERROR HANDLING
There are various conditions that cause errors when
using relative relative files. fLIes. The BASIC 7.0 variable DS$ contains
the error codes and descriptions for disk errors.
If the disk drive light is flashing and the program has
ended, ended . you you should type type PRINT PRlNT DS$ in in direct direct mode mode to to
display d.isplay the the error and to tum offthe off the light. You may also
have to type DCLOSE DC LOSE if the light stops flashing but remains
lit.
In general when a program writes to a relative file
for the the first first time, time. an an error error 50 50 "Record "Record Not Not Present" Present" ococcurs. This error occurs when the pointer is set with the
RECORD RECORD statement statement to to a record which has not not yet yet been been
wrinen. written. (In our our sample sample program program above. above, this this error did
not not occur occur since the the total total length length of the three records was
less less than 256 characters.)
The best way to handle the error 50 problem is to write
the the highest numbered record when the the file is first opened
and then then read read DS$ DS$ to clear clear the error. Assume Assume we knew
that we wou.ld would never have more than 40 records in the
file. We We could open open it and and write write to to the the 40th 40th record record this this
way: way:
1 DOPEN. DOPEN, "TEST" ,Lll) ,LIt)
2 RECORD#!, RECORD#l, 41),1 4t), 1
3 3 PRINT#l,"DUMMY"
PRINT#!, "DUHMY"
4 PRINT DS$
5 DCLOSE
Now the space on the disk has been a1.located allocated for 40 records,ords.
the 40th record has dummy data in it, it. and the error
50 has been cleared by line 4. 4. If we later need to
put more than 40 records in this fiIe, fLle. we may simply
open the file again, put the RECORD pointer to the new
maximum number, number. and write the additional records. We
must read DS$ each time a record is accessed which has
a higher record number than any previously accessed.
That is an advantage of writing the highest numbered
record first.
Another suggestion. Put your RECORD# RECORDH statement
immediately before the corresponding PRINT# PRlNTH or [N­
PUT# PUTH statement. A bug in BASIC gives improper values
of DS$ if a GETKEY statement is between the REC­
ORD# ORDH and PRINT# PRlNTH statements, statements. for example.
Whenever a program opens a a ftIe, fLle. it should houJd read DS$
and act accordingly accordingly. . YAL(DS$) Y AL(DS$) gives the error number
of the most recent disk input or output. A value of
o means that the file access was without error.
An An error error will occur if we try to write data which contains
more characters than the record length length specified
for for the the file. For that reason, reason. the program shou.ld should carefully
check the length length of each string of data before it
is wrinen written to the ftle. file. We will see how to do that in the
24 AHOyt AHOY!
relative file model to be discussed. discussed .
INTO THE FIELDS
Relative files are more flexible if their records are subdivided
into smaller segments cal.led called fields. Suppose we
want want to store the the names names ofthe of the planets and their numbers
of moons in a relative file me. . Each record should contain
two fields: fie.lds: a name field and and a number field. field . The records
for for Earth Earth and Mars would would look like this: this:
Field 1 --v ---v
Record #1: U: EARTH
Record 12: #2: MARS
v--Field v---Fie1d 2
1
2
We could create variable length fields or fixed length
fields. For example, example. Field I (the name field) of Record
H # I must be at least five characters wide, wide. whereas Field
I of Record #2 would need to be only four characters
wide. The sample program on page 123 uses fixed length
fields. We will simply pad the data in each field with
spaces as necessary.
For example, example. let Field I have a length of 14. 14. That
is longer than the longest name we have to store. store. Let
Field 2 have a a length of 10. 10. That is certain.ly certainly wider than
necessary. Ten characters will allow us to store most
floating point numbers easi.ly. easily.
Once we have defined the field lengths, lengths. we can calculate
the record length. The lengths of the fields add up
to 24. We must add one for the delimiter at the end of
each record. record. That gives a record length of 25.
Field 1I starts at character I and is 14 characters wide.
Therefore Therefore Field Field 2 starts at character character l5 15 and is 10 characters
wide. The The delimiter delimiter fills the 25th character character position
in each record. The record for Mars and its numberber
of moons looks like this:
Character Character iI # 1111111111222222
1234567890123456789012345
MARS __________ 22 _________ A
The The number, number. structure, structure. and and control control ofthe of the fields is up up
to us. The RECORD statement does allow us to move
the pointer to a specific character within a record so that
only a part of a record may be read or wrinen. written. But we
will will not not use that that method method of of selecting selecting fields. fields . Instead, Instead. we we
will always read the entire record into a string variable.
We will wiH read or write the desired substrings, substrings. then we
will write the modified record string in its entirety back
to disk.
READY TO MANIPULATE
Now that we have covered the background of relative
file me handling, handling. we are ready to put our knowledge into
practice. practice. Refer to to the program Planetary Planerary Moons DaraDatabase on page 123. This program creates a relative file ftle
called PLANETS. PLANETS. The file fLle has a record length of 25
as defined defined in line line 50. 50. SP$ is a string of 24 spaces to

ON WITH THE PROGRAM
Now we're ready to take lake a look at the SPRlTE2 SPRITE2 pro­
addressing- addressing-a a form of addressing in which the Y register
and a lWO-byte two-byte zero-page pointer are used in the folgram.
Actually, it's an improved version of the program lowing format:
that appeared in last month's column: a high-resolution
program that printed a message in quadruple-size characters
on the C-128 screen. This month, the program is
LDA (POINTER),Y
(POINTER) ,Y
expanded into one that also includes an animated sprite Before indirect indexed addressing is used used in a pro­
routine.
gram, a base address must be placed in a two-bYte two-byte zero
In its newest form, the program copies a character set page pointer, and an index value must be placed in the the
from ROM into RAM and then prints a message on the Y register. Then, when a statement that uses indirect in­
screen in large type. It then clears a bit map for sprite dexed addressing is encountered, the value stored in the
0, copies some data into the bit map from from the character Y register will be added to the eight-bit address pointed
set in RAM, and places an expanded sprite in an area to by the pointer, and the accumulator will be loaded with
out of viewing range at the top of the screen. Next, the
the contents of the resulting resuIting address.
sprite descends into viewing range, and maintains a slow
To use INDFET, this is what you have to do: Store
descent until it reaches a predetermined position. Then a base address in a zero-page pointer, load the accumu­
it stops and becomes a pan part of the message displayed on lator with the address of the pointer, load load the X register
the screen.
with the desired bank bank number, and load the Y register
THE 'INDfET' 'INDlET' ROUTINE
with an index. Then you can load load the accumulator with
any value you wish by simply doing a JSR to memory
One noteworthy feature of the program is its use of address $FF74. When the routine routine ends, the value that
a C-128 Kemal Kernal routine routine called INDFET, which has a call
has has been fetched will be be in in the accumulator, and the C­ C-
address of $FF74. With the help of the INDFET rou­ 128 will still be in the memory bank bank that it started out in.
tine,tine, a program can load the accumulator with any val­ Now you know how to set up a high-resolution proue
from any of the C-128's 16 memory banks, without
leaving the memory bank that is currently active.
gram on the Commodore 128, and how to program the
C-128's sprites. 0
The INDFET INDFET routine works much like indirect indexed SEE SEE PROGRAM LISTING LISTING ON ON PAGE PAGE /20 120
===========================================
30 30 AHOrt AHOYI

all over over the the screen and and ruin your your masterpiece. masterpiece. Second, the the
palette palene used used for the the FILL FILL operation operation must be the same same one used
to to draw draw the the oulline outline of of the the shape shape to to be filled flJIed. . Before performperforming any FrLL FILL operations where there is even a remote chance chance
that that you you save the the current screen to to the the safety buffer by hitting hining
the the 'OS" S" key. key. That way, if if you you mess mess up, up, you you can hit hit "R" to to recover
your screen. screen.
Note that in in any of the the drawing modes, modes, you you can can hit hit the the oS' oS·
key to save the current screen to to the buffer, or "R'" "'R" to to restore
the the screen from the the buffer. Please note that that it it takes takes approxiapproximately 10 seconds for the program program to save or or restore a picture picture
from the the buffer. To To go go back back to to the the MENU MENU screen, press any any
other other key.
MENU SELECTION
When When you you first run the the program, you you will will be greeted with
a menu menu screen. screen. The The upper 4/5 4/5 ofthe of the screen screen is the Main Main Menu;
the the lower lower ponion ponion is the the Color Color Menu. Menu . Most Most of of the the commands
are are self explanatory, explanatory, or or have have been explained above. To To make make
a a choice, choice, use use the the joystick joystick (plugged (plugged into into Pon Pon 2) to to move move the
cursor cursor to to the the box box of the the selection selection you want want to to make and and hit hit
the the fire button. bunon. In addition addition to to the the command commands already covered,
there are a few few more more available available from the Main Menu Menu. .
On the the left left hand hand side, side, near near the the center of of the the screen, screen, you you
will will find two two boxes boxes marked marked LARGE and and SMALL. These These boxboxeses allow allow you you to select the size size of your pen pen strokes. strokes. When When you you
are in LARGE LARGE mode, mode, the the cursor cursor will will be be twice twice its normal normal size. size.
In In addition to to the the two brush brush (pen) (pen) sizes available, available, you you will will be
THE ULTIMATE CONTROL INTERFACE
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312-948-9200
.. An alJlo-dial modem Is requIred required to use the phooe-dialer leatule. teature.
"Convnodofa 'Commodore 128... 128 ... 18 is a lrademaril trademark and Commodore 64 6415 Is a registered lrademartl trademark 01 Commodore
Electronics, EIec:ll'onlcs, lid.. ltd., Sidekick Is 8 trademarlt trademark 01 Bot1and BOOaOO International, International. Inc.
Cll985 Cl I985 Tlmeworxs, T1mewof1(s, Inc. AM rights reserved.
PARTNER! A cartridge-based program with eight
convenient memory-resident desktop "accessories"
that operate "concurrently" with other C12S:. C12S:" software
programs.
Like Sidekick""" Sidekick·,., PARTNER automagically suspends
the existing program in your computer
while you use the PARTNER accessories. When
you are through, press a button and PARTNER
returns you to the point in your program where
you left off.
Accessories at your command:
• Appointment calendar calendar and date book: Keep • Phone list & auto dialer: Keep track of important
track track of of appointments and and deadlines. At the the press of a a phone phone numbers. At At your your command, the the computer computer will will
key, you'll be be able to to review your your appointments for for a day, search search through through your your list list for for the the number number you you want, and and
week, or or month. Months may be be viewed viewed in their their entirety entirety automatically automatically dial dial the the number number for for you." yOU .-·
in a traditional calendar format, and then printed out. • Screen print: At the press of a key, the contents of
• Memo pad: Write yourself important notes. Print them
out out on paper paper or save them onto disk.
your computer computer display will will be duplicated duplicated on your your printer.
•• Name Name and and address address list: list: Keep Keep track track of of important important
names and and addresses. Available Available instantly, any time time you you
are are using using your computer.
• Calculator: A multi-function calculator with an
optional "paper tape" that prints out out your calculations calculations on
your your printer.
• Typewriter: Typewriter: Turns Turns your your computer computer and and printer printer into into aa
traditional typewriter.
• Envelope Envelope addresser addresser & label label maker: maker: Use Use this this
feature feature and your your name and address address list to to address address
envelopes or or create mailing mailing labels - qUickly, quickly, without without
leaving leaving the the software software you you are are working working with.
PARTNER PARTNER 128 128
THE 1sT THE 1 DESKTOP ACCESSORY THAT
WORKS IICONCURRENTLY" WITH
OTHER C128 SOFTWARE.
ST DESKTOP ACCESSORY THAT
WORKS IICONCURRENTLY" WITH
OTHER C128 SOFTWARE.
Other features:
• SwiftDOS: SwiftDOS: Allows Allows you you to to access Commodore Commodore disk disk
drive drive commands commands any any time.
• SwiftLock: Enter your your secret code code before before you you leave
your your computer. The keyboard will will be be locked until until you
re-enter your your code.
• Extended Printer Control: Allows you to send commandsmands
directly to your your printer at any time.
•• SwiftLoad: SwiftLoad: Allows Allows your your Commodore Commodore 1541 1541 disk disk drive drive to to
load load as as fast as the Commodore Commodore 1571 disk disk drive.
Suggested Suggested Retail Retail Prices: Prices:
C128 C128 (128K, 80 80 column):
$69.95 $69.95
C64. (64 K, 40 column):
$59.95
Available at your favorite Dealer,
or call call Timeworks Timeworks today.
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Reader SelVice Service No. 223

disk. disk. Now enter the C-128's C-12S's built in monitor by hitting hining the f8
key. TYpe Type M OEOO OEB8 and press RETURN. The screen will
fill with hexadecimal numbers. numbers. Move the cursor up to the lines lines
and change the hexadecimal bexadecimal values to match those in in the listing
of the second program (SPRITE DATA). DATA). Be sure to to press
the REfURN RETURN key at each eacb line after you have bave made the changes.
Once you have finished cbanging changing the values to match those
in the listing, move the cursor to a blank line and type M ooBOO OOBOO
ooBlO. OOBIO. Change the values in these locations to to match those
of listing three (ML ROUTINE). You can now save the program.gram.
TYpe Type S"ART S"ARf SPR",8,+3584,+4096 SPR",s, +3584, +4096 and and press RETURN. RETURN.
Now, type S"ML",8,OBOO,OB14 S"ML",S,OBOO,OBI4 and press REfURN. RETURN . You can
now exit ellit to to BASIC and type type in The Anist. Be sure to save
The Anist Artist before anempting attempting to run il. it.
FUTURE EXPANSION
You may have noticed that the upper right hand comer corner of
the Main Menu screen contains a large blank box. box . I purposely
left this box blank for future expansion. expansion. Here is a brief description
of how how the cursor input routine works in case you
would like to add some features to the program.
Lines 62-74 check to see where the cursor is along the yaxis
when the fire bunon button is pressed. Control Control is then transferredfurred
to to the appropriate section section (Lines 78-126) to to determine determine
where the cursor is along the x-axis. x-axis. This is wbere where the routinetine
actually determines what function was was selected. selected. Thke note
of line 62 62. . This line calculates the x and y coordinates of the
cursor sprite and then translates it to x and y coordinates for
a 40 column by 25 row screen. The upper left hand comer corner
is location (0,0) and the lower right hand comer corner is location
(39,24).
To demonstrate the process of adding new commands (options),tions),
I will show you how to add a BORDER command. command.
This will allow you to change the border color of the graphics
screen. screen. First, we we have bave to decide how the command will work. work.
1b keep things things simple, I have decided that a box with the word
BORDER in it will be used to activate the BORDER command.mand
. The user could move the joystick up to the box and
hit the fire bunon to cycle through the 16 available colors.
The next thing to do is add the command command box itself. itself. I decided
to to add the command at Line 500. 500. Here are the lines
needed: needed:
51JCJ Y)() WINDOW24,1,39,14 WINDOW24 ,I,39,14 : PRINT"[WHITE][ PRINT"[WHITE][8 8
" "][ RVSON] RVSON J ": ": PRINT" BORDER [RVSON] [RVSON J " :
PRINT" [8 " "][ RVSON] RVSON J ": PRINT" [RVSON][ W
HITE][ HITE][9 9 " " "]": "J": WINDOW), WINDOW) , 1),39,24: () , 39 , 24 : RETURN
The first WINDOW command makes a a window in the big
blank box on on the Main Menu screen. screen. The The BORDER command
is then printed in the upper left hand comer corner of that box. box . The
screen screen is then returned retu rned to normal with the second WINDOW
command, and the program then returns from the subroutine. subroutine.
To make sure that our new command is printed along with
the Main Menu screen, we have to have a GOSUB to our rouroutinetine from the routine that prints the Main Menu. Menu. Add the command
GOSUB 500 to Line 714, 274, right before the RETURN
statement.
However, just adding and printing the command command is not
enough. We also have to add a routine to check for and activate
the new command. Type TYpe in the following Line: Line:
83 IFX>23 IFX >23 AND X

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4.
PIGSKIN PROGRAMS
FOR COMPU-COACHES
New titles give football foolball fans
lots of gaming choices
.y By Anli. Arnie Katz Kat.
........ and Bill K_It•• Kunkel
The United States Football
League's challenge to the
NFI:s monopoly monopoly failed, failed ,
but Pete Rozelle's group
still isn't the only game in town for
football fans. funs . There's a stadium built
into every Commodore 64 and 128,
and software software publishers have ftlled it it
with a rich assortment of great gridiron
disks. disks.
Four football football games have appeared
for the C-64/128 C-64/128 since Ahoy! Ahoy! last
studied studied the category. category. As if that were
not enough good news for computer
sports fans, funs, the new entries reviewed
here represent a truly amazing amazing variety
of game-formats.
game-formats.
Whether the computerist enjoys
pure arcade-style action or undiluted
statistical accuracy, there's a firstquality
game game that that can fill the bill. The
four newcomers, newcomers, together with the
previously available On Field Footballball
(Gamestar/Activision) and and Super
Bowl Sunday (The Avalon Hill Game
Company), insure that there is a programgram
to suit suit every football funcy. fancy.
Fans of action-oriented gridiron
simulations can start dancing in the
end zone: zone: Electronic Arts Arts has released
a Commodore version of !magic's
excellent Touchdown Football.
In this contest, contest, the coach ofthe of the offense
has a choice of eight formations,tions,
eight pass patterns, and three
possible line blocking schemes, schemes, plus
full kicking options. The defeoder defender selects
from among eight regular and and
two kicking plays. plays. All selections selections are
entered via joystick, using a series of
pull-down menus. menus.
Once the strategy is set, the onscreen
center snaps the ball. The userer
takes direct control ofthe of the quarter- quarter-
Football mixes action and stolistics. statistics.
READER READER SERVICE SERVICE NO. NO. 213 213
Thuchdown Touchdown Football: 8fomwJions.
8 formations.
READER READER SERVICE SERVICE NO. NO. 2/4 214
back and either guides him through
the line on a rushing play or sets up
for a pass to a previously designated
receiver.
A completed pass causes control
of the onscreen athlete to immediately
shift to the receiver. A pass catcher
can try to dart downfield down field for extra
yardage. yardage. On On defense, defense, meanwhile, meanwhile, the
computer coach maintains joystick
control over the middle linebacker linebacker
IIITI.TAIIIMIIiT
.onwa••••CT.ON
.OPTWA.I.leTIOIl
while the rest of the team moves according
to the preprogrammed instructions.structions.
. . Touchdown Touchdown Football presents its
two six-man squads in in a realistic, realistic,
three-quarters perspective with horizontal
scrolling, visible officials,
cheerleaders, and and a pigskin that casts
a a shadow. There There are punts, punts, field
goals, goals, and even interceptions as the
two squads march up and down the
gridiron in this head-to-head or oneplayer
action contest.
Unfortunately, this excellent program
by by Mark D. Klien, Klien, Michael
Becker, and Wlifredo Wilfredo Aguilar was
originally designed to be be played on
the 128K ffiM reM PC and PCjr systems, systems,
and the the translation to to the the Commodore
Commodore
64 causes several problems. For one
thing, the play entry system was created
fur for use with a tw()-button two-button joystick. joystick.
In the original, one action action button
brings up the options and the other
enters commands. Once the play bebegins to unfold on the field, field, the dual
fire buttons allow the quarterback to
throw to either the upper or lower
wide receiver. receiver. While the lack of a
second action button does not cripple
the game, it significantly complicates
the command control scheme. scheme.
Another noticeable flaw flaw is that the
graphics are not as sharp as one
might expect in a game as sophisticated
as Touchdown Football. Football., - The
gamer must be be able to follow the individual
players as the lines collide,
but this is often next to impossible
due to the muddy muddy animation. animation.
Touchdown Football, even with
these minuses, minuses, is still still the best action action
football simulation around. The extensive
choice of offensive and defensive
plays and faultless joystick re-
AHOYt AHOYI 47 41

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64 AHOYI
Reader Reader Service s.tYlce No. 272
64 AHOYt
Fulltone Fulltone dumps dumps may may be be further funher influinfluencedenced by the starus status ofthe of the NLQ NLQ mode.
Finally, Finally, directories directories will will be automaautomaticallytically listed listed to the printer. printer. All you you
need do do is issue the appropriate appropriate comcommand over over the the command channel channel or
via via a a double double escape code sequence
and send send the data to the interface via
a file me with with secondary secondary address address one. one.
"Now "Now that that sounds sounds great; great," we we hear
you you exclaim, "hut "but you you have have obviously
taken taken leave leave of of your your senses. The The
screen screen dump dump sounds like like a a useful
gimmick gimmick but but aien't aren't all interfaces interfaces supsupposed to send send text text files to the the printprinter?er? Besides, what's wha(s the big big deal deal about about
listing a directory?"
The real gimmick is that you don't
have have to to send send the the data data directly directly to to the the
interface. From the time the download
command is issued, Device One
patiently patiently listens listens for any any and and all serial
bus fIle transfer activity between
the the computer computer and the disk drive. drive. This
could could be a LOAD LOAD or or SAVE SAVE operaoperation or even a VERIFY. Once a file
transfer commences, Device One
greedily greedily gobbles a copy copy of of every every
passing byte till the file has completely
gone by. Only then does processing
begin. begin. In In the case case of of a VERIFY,
the the possibilities possibilities are awesome. Any Any of of
the four file ftle formats may be passed
on on to and processed processed by the interface interface
without disturbing the the current current concontentstents of the computer's RAM!
In the the case of of text text and and directories,
printing will start start as soon as the file
transfer is complete. Pictures are banhandIeddled differently. Printing Printing is delayed delayed
till a series of lines are sent sent to the the ininterface. Ifthese If these are all blank, just just the
picture picture will will be be printed. If If the the lines lines
include include text, it will overlay overlay the image.age.
This This effect effect works works well with with a
halftone halftone dump dump as the the image image forms forms a
background background to the text. It is even possible
to offset offset the the image image margin margin and
print text text and and a graphic graphic side by side.
Downloaded images must be pure,
8000 byte bit bit maps, stripped stripped of all all
color color data. Flexidraw, Flexidraw, from from Inkwell Inkwell
Systems, Systems, is is the the only only graphics graphics packpackage we know ofwhich of which normally normally saves saves
images in this tltis format. All others
combine their image image files, fIles, with the
bit bit map's map's color color information, information, in varying
ways. To get around this tltis problem,

@
Disk Disk Catalog Catalog System System
* tr Catalogs up to 640 Disk Directories Direaories
1280 with with 2 drives
* tr Indexes and Alphabetizes over 5000 Titles
10.000 10,000 with with 2 drives drives
* tr Unique Disk ID'S not necessary
* tr Automatic Entry from Disk Direaory Directory with
Manual Selection. Seleaion, Edit Edit and and Cross Cross Reference
* tr Print - Alphabetized Index of all Titles. Titles,
Directories Direaories by by disk. disk, Disk labels and and more more
* tr Printer not required
Search Function Funaion defaults to the Screen
* tr Search - find any Title in to 10 seconds
* tr Sorts 1000 Titles in 8 seconds
* tr Runs on Commodore C-64 or C-128 C- I 28 with
I 154 1541I Drive Drive I 2 154 1541I Drives Drives I Dual Dual Drives
S29 S Z 9 9S 9 5
(u.s.) (u.s.) Includes shipping shipping within USA USA
• Includes Includes backup backup copy copy of of program program disk
Add 54 S4 for COD Orders - 56 S6 for Shipping Outside of USA