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Tune in again next month. 



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wL-UMU 

MAGAZINE 
INC. 



RO. Box 1448 

Santa Barbara, CA 93102 

(805) 962-6271 

JULY 1981 



Side 



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Turns 
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Count 
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Title 



6 Line Cover 

Wanderer 

Music Master Instructions 

Music Master 

Sample Song 



Fast Graphics Instructions 
Fast Graphics 
Jerusalem Adventure 
Read ing 



17 

47 

100 

144 

238 



11 

60 

113 

210 



263 
285 
3 24 
3 58 
433 



261 
303 
337 
413 



10 
28 
59 
84 
140 



6 

40 

66 

124 



155 
168 
191 
211 
255 



153 
178 
198 
243 



Set 

of ; 



CLOADing Notes - This tape may load at an ODD RECORDER VOLUME. 

increase it slightly until the tape loads. If the first copy 

there. Model I only: Put an AH radio very close to the keyboard, tune it to a non-station, and you 

loading in. Adjust the recorder volume so the hash from the computer sounds 'cleanest' during a load. 



the volume LOWER than normal for vour first attempt , then 
program won't load, try the second. That i s why it i s 

1 i sten to V tie tape 



Model III notes - Load the tapes at the LOW speed (POKE 16913,0). An occasional program will MOT run. 
lower case goofs in some programs. Arrow keys often are translated as follows: (t, 4>, ^- , ->) = {[, \, 



There may he 



ipper and 



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6 Line Cover draws a symmetrical pattern on the screen with 6 (count 
6) lines marching in unison. 



em 



Wa nd e r e r is one of those real-time games that looks so simple you feel 
embarrassed to be seen playing it. Ten games later the game is still simple, 
but you no longer feel embarrassed - you are addicted! Note - the program 
PEEKs the screen memory to see if you have hit something in your 
'wanderings'. This may cause problems, if you have the R/S lower case mod in 
your machine. Later in this editorial there will be more (mis) information on 
this recurring problem. 



Playing in the "I'd rather have a piano" department you will find Music 
laster . Now you can compose and play little ditties on the TRS-80 ! Irritate 
your friends. If your composition isn't quite perfect, you can edit it (you 
can even insert forgotten notes, unlike a certain plug in ROM pack sold by a 
large corporation for their color computer allows you to do). To send the 
dog scurrying under the bed right away, load in Music Master and run. One 
item in the menu allows you to load in previously saved compositions. Choose 



CLOAD July 1981 Page 2 

that item and load in Sample S ong. When that is finished loading, choose the 
menu item that allows you to play that song. Look at that dog goi 

For your convenience, the listings of the note and duration codes from 
the instructions are listed below: 



Scales 



Low 



Med 



Hig h Higher 



Note Durations 



Codes 



C 

C#/D 

D 

D#/E 

E 

F 

F#/G 

G 

G#/A 

A 

A#/B 

B 



flat 



flat 



flat 



flat 



flat 



n/a - 



n/a 


C2 


C3 


C4 


n/a 


C#2 


C#3 


C#4 


n/a 


D2 


D3 


D4 


n/a 


D#2 


D#3 


D#4 


El 


E2 


E3 


E4 


Fl 


F2 


F3 


F4 


F#l 


F#2 


F#3 


F#4 


Gl 


G2 


G3 


G4 


G#l 


G#2 


G#3 


n/a 


Al 


A2 


A3 


n/a 


A#l 


A#2 


A#3 


n/a 


Bl 


B2 


B3 


n/a 


not 


available 


for 


use 



Whole WI 

Half H 

Dotted Half H. 

Quarter Q 

Dotted Quarter Q. 

Eighth E 

Dotted Eighth E. 

Sixteenth S 

Thirtysecond T 

Double Whole WW 

Whole and Half WH 
Whole and Quarter WQ 



You will need 
Music Master. If 



to plug the large grey recorder plug into an amplifier for 
you don't have an auxilliary amplifier, you can use the 
Just push the PLAY/RECORD switches down (you will have to 

back where the cassette 



recorder itself. 

hold in the anti-record protection switch at the 

goes) and listen through an earphone plugged into the earphone jack on the 

recorder. Your neighbors will thank you... 



Do you ever wonder how some of our authors do those 'fast graphics'? Or 
do you know how, but it seems too complicated to mess with? Did you tie your 
shoes this morning? Fast Graphics has nothing to do with tying shoes (or the 
price of pickles in Belgium, for that matter) but it does make it EASY to 
generate string variables that contain fast graphic data! 

Fast Graphics is a unique program in some ways. You use the program to 
generate fast graphic strings, then you delete all the rest of the program 
and build your own program around those strings you generated. The most 
unusual thing, though, is that you run the program one time to set the 
dimensions of the block that you will be drawing in, then you RUN the program 
again to draw in that block and pack your string with the info. 

Wait - did I say, "RUN the program again"? That reinitializes all of the 
variables! Then how does it: know the dimensions of the block to draw in? 
Those dimensions are saved in the program itself! In line 4 there is a 
string variable (V$) that is 3 bytes long. • It holds the width, length, and 
number of bytes for the block you defined. Listing this line after the 
program has been run can give some weird results due to the values of the 
bytes in V$. 

The program was done this way to allow you to go in and add your string 
variables to pack or to change the string variable names (it is initially set 
up to do G$ (1)-G$ (10) ) after setting the dimensions of the block. 



And now, 
find a blank 



a little lesson on fast graphics - 
wall. Oh, you want to know how to 



grab a can of spray paint an 
do it on the TRS-80... 



If you enter 'PRINT CHR$(89)' into your TRS-80 you will have a 'Y' 
printed on the screen. You get the same thing if you enter 'PRINT "Y"', 
Now, if you enter 'PRINT CHR$(153)' you get a 'V. But you can't enter 
'PRINT "y ' . Or can you? 



CLOAD July 1981 Page 3 

If we let 'A$="Y'", and then 'PRINT A$ ' , we get a 'Y' on the screen 
(again!). Now, we 'PRINT ASC(A$)' and we get '89' (the ASCII value of 'Y'). 
If we could change that value to 153 (89+64), then A$ would equal "4" and we 
could "PRINT A$ ' to print a '^' ! Well, the value of A$ ('Y') is stored in 
memory somewhere. We just have to find out where it is stored and change the 
ASCII value from 89 to 153 using the POKE command. And to find out where it 
is stored we have the VARPTR instruction. Without going too far into the 
VARPTR instruction and how it is used to find the location of A$'s value 
(that is another whole lesson), below is a little routine to show how fast 
graphics strings can be created: 

10 A$="@ABCDEFGHIJKLMNOP" 

20 PRINT A$ : ' ORIGINAL STRING 

30 PRINT VARPTR (A$) : ' LOCATION IN MEM OF 5 BYTE STRING DESCRIPTOR 

31 ' FOR A$. THE 2ND AND 3RD BYTES GIVE THE 

32 ' ACTUAL LOCATION IN MEM OF A$ VALUE. 

40 X = PEEK (VARPTR (A$)+l) + PEEK (VARPTR (A$ ) +2 ) * 2 56 

41 ' X CONTAINS LOCATION OF FIRST CHAR IN A$ (@) 

42 ' X = LSB + MSB * 2 56 

50 L = PEEK (VARPTR (A$) ) : 'GET THE LENGTH OF A$ 

6 FOR I = X TO L-l : ' LOOK AT EVERY CHAR IN A$ 

70 POKE I, PEEK (I) +64 : ' ADD 64 TO ASCII VAL OF EACH CHAR IN A$ 

80 NEXT I : PRINT A$ 

After entering and running the above routine, list line 10. In the Model 
I, A$ will look like gobbledegoop, and in the Model III, A$ will be filled 
with graphic characters. You have just created a fast graphic string! Armed 
with this technique (or the Fast. Gr ap hic s program), you can create pictures 
that are drawn on the screen in a flash!" 

Now for a pilgrimage to the Holy Land. Jerusalem Adv entu re puts you 
there - and won't let you out! The BREAK key is disabled just to make it a 
little harder for you to cheat. You can enter 3 character abbreviations for 
the commands (OPE D00 for OPEN DOOR) and you can save and load the current 
game status with the SAVE and LOAD commands. If you really need to leave 
Jerusalem, try QUIT. 

A bit of warning - if you find yourself stuck and you need a hint on how 
to get past a certain obstacle (like how to get. off the streets of 
Jerusalem), don't call here! I take a sadistic pleasure in NOT giving clues 
to adventure games. I consider that part of the FUN (?) of the game. 

When it takes you 2 1/2 hours to read the Sunday comics, it's time to 
practice up on your reading. Read ing flashes words and phrases on the screen 
for a preset length of time. Improve your reading speed, and you may find 
enough time to tackle the sports section... 

In the uPPeR And loWEr CAse . . . ! 

I try not to harp on certain topics (sure, sure), but the way Radio Shack 
designed their Model I lower case mod really BUGS me. 

I do not have this mod in our machine and I don't have access to a TRS-80 
that has one, so I'm just relaying what I've heard from users out there. If 
you PEEK or POKE the screen memory, the values received or the characters 
displayed on the screen are different for a lower case machine than for the 
standard upper case only machine. Some programs (last month's Disk Cat alogue 
and this month's Wanderer , for examples) don't digest these differences well. 

All is not lost - rather than modifying programs (adding 32 to each value 
returned when PEEKing the screen memory), just load in your upper-lower case 



CLOAD July 1981 Page 4 



driver ('ULCDVR') first. This seems to work in most cases, but you may have 
to use capital letters to answer questions that the program asks. Thanks to 
William Richrath of Elmhurst, IL (among others) for this info. 

The users speak again... 

There is a stack of notes here from many of you with one thing in common 
- they all tell of ways to get last month's Breakthrough on disk. The most 
common suggestion is to use 'TDISK' from Acorn Software (534 N. Carolina Ave, 
S.E., Washington D.C. 20003). Stewart Schiffman of Pegasys Systems (4005 
Chestnut St., Philadelphia, PA 19104) suggested this method: 

1) Place this code in memory starting at A000 (40960 decimal): 

HEX ASSEMBLY DECIMAL 

21 00 40 LD HL,4000 33 64 

11 00 80 LD DE,8000 17 128 

01 99 0F LD BC,OF99 1 153 15 

ED B0 LDIR 237 176 

C 3 00 00 JP 195 
Use a monitor program or POKE the values from BASIC. 

2) Go into Level II BASIC (not DOS BASIC) and load Breakthrough . 
When it is through loading, type ' /40960 ' <enter> . 

3) You are now in DOS again. Add the following code starting at 
8F9A (36762 decimal) : 



HEX 
F3 

21 00 80 
11 00 40 
01 99 0F 
ED B0 
C3 1C 48 



ASSEMBLY 
DI 

LD HL,8000 
LD DE,4000 
LD BC,0F99 
LDIR 
JP 481C 



DECIMAL 

243 

33 128 

17 64 

1 153 15 

237 175 

195 28 72 



4) Dump the program to disk: start = 8000, end = 8FA8, and 
entry = 8F9A (decimal: 32768, 36776, and 36762). 

Note: the instructions for Breakth ro ugh will not be saved to disk using 
ei ther method . 

Alien fans (March, 1981)! If you are running TRS-DOS, you can run Al ie n 
from disk by naming it 'ALIEN/CMD*, then typing 'CMD" I" ," ALIEN" • from DOS 
BASIC. 

Stay tuned next month (I think) for a program that allows you to save any 
system program to disk and run it from disk. 



*************************************** 

* * 

* IBM PRIN TER * 

* * 

* IBM I/O Selectric (15"), Printec * 

* port, driver program and word * 

* processor for use with TRS-80, * 

* 16K or 32K Level II. Prints upper/ * 

* lower case - used - excellent * 

* condition! $600 & shipping. * 

* E. Zoltanski , 2463 Nebraska Avenue, * 

* Toledo, Ohio 43607. * 

* * 
*************************************** 



Later , 
ed . 



If you have a Color Computer, 
You will want to 
get CHROMASETTE 
Magazine ! 



Chromasette Magazine 

RO. Box 1087 
Santa Barbara, CA 93102 




(805) 963-1066