SNAP (Spectrum)
by Bill Lythgoe
from Sinclair User 26 (May 1984)

SNAP IS A GAME for two players in which the screen and border
continually change colour. When the colours match, player one should
press 1 and player two should press 0. The player to press first gains
a point but a point will go to the opponent if you press at the
incorrect time. Written for the 16K Spectrum by Bill Lythgoe of
Shelvington, Wigan.

VARIABLES used by the program:
a$  1st player's name
b$  2nd player's name
a   1st player's score
b   2nd player's score
w   Winning score
bo  Border colour
pa  Paper colour
n   Used to vary the note in BEEP statements

  10-  60  Prints the opening titles
       70  Waits for a key to be pressed
 100- 120  Input the players' names and winning score
      130  Sets players' scores to zero
      150  As the paper colour keeps changing, this command ensures
           that anything printed can still be read. If the paper is
           dark, the ink will be white; if it is light, the ink will
           be black. See page 111 [page 83. JimG] of the manual.
 170- 180  Picks random paper and border colours and clears the screen
           to those colours
 190- 200  Prints the players' names and scores
      210  Pause for a random amount of time
 220- 250  If either player is pressing a key and the colours are the
           same, their score is increased and printed. If the colours
           are not the same, their opponent's score is increased.
      260  Clears the message printed in lines 220-250
 270- 280  Alters the value of n and limits it to 13
 290- 300  If either of the players has reached the winning score,
           print it and GOTO the end of game routine
      310  GOTO start of game
 500- 530  Print instructions to play again
      540  Wait for key to be pressed
 550- 560  If you have chosen either option, GOTO the correct line.
           If not, the program will run out of lines and STOP.

This is a fairly straightforward game but as it might be used by
people who know nothing about computers it should be error-trapped -
that is the program should not stop if an incorrect key is pressed.
When one player presses a key in lines 220-250, if that is the winning
press the program goes to line 500 and waits for another keypress, if
the player has not released the key quickly enough the program stops.
By adding the new line 500, the program waits for the key to be
released before continuing.

500 IF INKEY$ <> "" THEN GOTO 500
505 CLS

Lines 100-120 can also be error-trapped, for example:

100 INPUT "1st player's name?";a$:
    IF a$="" THEN PRINT AT 20,4;"You must enter something": GOTO 100
105 CLS

There is more error-trapping you can do - that is for you to decide.

If the program is to be used by very young children it would be useful
if they had to press only their half of the keyboard rather than one
key. For example, add:

210 PAUSE 50+RND*50
212 LET st=(IN 65278<>255 OR IN 65022<>255 OR IN 64510<>255 OR IN 63486<>255)
214 LET nd=(IN 61438<>255 OR IN 57342<>255 OR IN 49150<>295 OR IN 32766<>255)
216 IF st=1 AND nd=1 THEN PRINT AT 10,12;"TIE":
    FOR t=1 TO 100: NEXT t: CLS: GOTO 160

If you have an Issue 3 Spectrum, alter all the 255s to 191.

Alter the beginning of the following lines to:

220 IF st=1 AND ...
230 IF nd=1 AND ...
240 IF st=1 AND ...
250 IF nd=1 AND ...


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AMAZE (ZX-81)
by Antony Joyner
from Sinclair User 26 (May 1984)

[The program as listed requires variables U, I and Q]
[to be defined by direct commands.              JimG]

AMAZE is a beginner's program written for the 1K ZX-81 by Antony
Joyner of Emsworth, Hampshire. Once LOADed the program will auto-run
and draws some interesting patterns which can be printed if connected
to a printer. After the pattern has been completed you can press any
key to see another pattern. Do not break into the program as it will
have to be LOADed again.


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SEQUENCE
by David Bond
from Sinclair User 26 (May 1984)

Copy the number sequence as shown by the computer without making
mistakes. Sequence was written for the 16K Spectrum by David Bond of
Hornchurch, Essex.


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--
Another Fine Product transcribed by:
Jim Grimwood, Weardale, England (http://www.users.globalnet.co.uk/~jimg/)
--
