Crawly Crypt Collection 1/crawlyvol1.bin/apps/misc/zx81/englzx81.txt

Text File | 1987-04-21 | 6KB | 105 lines

 TIMEX SINCLAIR ZX81 EMULATOR (AN ENGLISH MANUAL)

  As you probably know, the ST's "open" operating system allows for
the emulation of a number of other computers through the use of software
or by inserting a hardware connection into the appropriate port on its
body (the cartridge port being the most common). Of course most Atarians
are familiar with the type of computers the ST has been called upon to
emulate from time to time, most notably the Apple Macintosh (Magic Sac,
Spectre GCR), IBM systems (PC Ditto, PC Speed, Supercharger), and even
the older Atari 8-bit systems (the PD ST-Xformer).

  Well, here's an interesting new program that I found through British
PD house Goodman PDL (tel. [phone]). This program, of German
origin, allows the ST to emulate one of the first home microcomputers,
the Timex - Sinclair ZX81.

  But, I probably hear you say, why emulate a computer which only had 1K
of memory, had a membrane QWERTY keyboard instead of regular type keys,
and required the user to save and load data via tape dump? Not to mention
also having to enter all your progams in capital letters only, since
the ZX81 only had enough room in its memory to handle the upper case
letters.

  Well I say, Why not? Even though it is primitive, this particular pro-
gram does allow  those fairly new to the computing game to get an idea
of what it was like in the headier early days of the home computer. And
besides, as I wizzed around, checking out the various of the 38 programs
included on the disk (that's right, so breathe a sigh of relief - you
don't have to develop a tape-to-ST interface to try this out) I must
admit I was having fun!

 Unfortunately, the programs' documents are only in German, so it was a
little hard for me to grasp it at first. To spare you that trouble, here's
a short description on how to run the program.

TO RUN...
1) Load disc and boot up
2) Double click on ZX81.PRG
3) A box should appear featuring a picture of a kindly professor-type
person (who, unless I'm wrong, is Clive Sinclair, the machine's father).
4) Clicking on the GO ZX81 prompt will take you right into the program;
clicking on PANIC will return you to the desktop.
5) A smaller blank screen should appear, with a "K" cursor.
6) In order to run a program, you have to load it in first. This is
accomplished in one of two ways:
   a) press "J" on the keyboard. The screen will then tell you to "LOAD".
Enter the name of the program on the screen with the keyboard, then press
ENTER. Then press "R" for run and press ENTER again.
   b) press "J" on the keyboard. Then, while pressing SHIFT, hit "P"
twice so that the screen now says " LOAD "" ". Now press ENTER. A GEM
file selector should now pop up which allows you to scroll through the
38 programs. Double click on the program you want with the mouse. With
the program loaded, press "R" and press ENTER again.

IN CASE OF EMERGENCY.....
   If you actually decide to write your own programs using this and
need to know the functions of each key, or if you forget which does what
on the keyboard, press the HELP button. The program will temporarily stop
and a picture of the keyboard will appear on the screen outlining its
functions. Likewise pressing HELP again will cause the keyboard to dis-
appear and the program to resume. (By the way, for more information on how
to program this beast, it might be wise to find either an original manual
for the ZX81 or one of the third party books written for it - I found one
in a surplus electrical shop. Also, for those in the Toronto area with a
modem and communications software, there's a BBS called TIBM Wizard (416-
743-6703) that offers Timex support, so it might be worth it to check it
out.)

TO SUIT YOUR NEEDS....
...... press UNDO. The program will temporarily stop and a GEM window will
appear, allowing you to choose the following options:
a) POWER PAK (memory configuration)- clicking the mouse on the appropriate
prompt will reconfigure  the program as either the standard 1K ZX81, a 16K
ZX81, or a whopping 48K MegaZX81.
b) JOYSTICK - this allows you to reconfigure the key settings in a game for
better response (but it doesn't use the ST joystick port, rather it util-
izes the keys to move cursors back and forth). Click on the appropriate
direction with the mouse, then enter the new numerical configuration.
c) CONT - resumes the program
d) BREAK - stops the program in progress and clears the screen.
e) RESET - resets the emulation to its opening parameters.
f) QUIT  - clicking on this causes a GEM window to appear asking if you
want to quit the ZX81 program. Clicking in the affirmative stops emulation
and returns you to the desktop.

THE PROGRAMS THEMSELVES
   No, there's no desktop publishing or CAD programs on this, nor can
you expect fancy graphics - but there are some neat things like bio-
rhythm programs, a demonstration of the movement of gas molecules, racing
games, a well-done (for its limitations) 3-D maze game, and crude but
effective versions of Breakout, Space Invaders and shoot-em-ups. Some of
the programs are only in German however, so you'll either need a transla-
tion guide or a German friend or relative to help you on that one. Also
some programs only run one word and nothing else.

   Well, that's the lot. I hope you get as much enjoyment out of this
program as I did learning how to run it. If you do find out some other
functions of this program that I should know of or just want to talk
about other things ST, leave a message for me on TAF Online (416-235-0318)
or Bits 'N' Bytes (416-532-1784).

                    Sincerely,
                              Daniel Dreibelbis