C64 CodeArt

by Daniele Olmisani

Please, see LICENSE file.

Hello World!

PRINT "HELLOWORLD!"

Generate random patterns with Commodore 64.

100 REM CODE-ART
110 REM [email protected]
120 PRINT "{CLEAR}"
130 REM PUT CHAR MAP AT 12288
140 POKE 53272, (PEEK(53272) AND 240)+12
150 REM DEFINE NEW CHARS
160 FOR K=0 TO 15
170  : READ A
180  : POKE 12288+K, A
190 NEXT K
200 REM DRAW RAND PATTERNS
210 PRINT CHR$(64.5+RND(1));
220 GOTO 210
230 REM CHARACTER DATA
240 DATA 016,016,032,192,003,004,008,008
250 DATA 008,008,004,003,192,032,016,016

Obviously inspired from the famous 10 PRINT CHR$(205.5+RND(1)); : GOTO 10

Sierpinsky Pattern

100 REM SIERPINSKY PATTERN
110 REM [email protected]
200 PRINT"{CLEAR}" 
210 FOR R=1 TO 25
220 : FOR C=1 TO 40
230 : : V = R AND C 
240 : : IF V=0 THEN POKE 983+40*R+C,160
250 : NEXT
260 NEXT
900 GET A$: IF A$="" THEN 900
999 END

Random music

10 POKE 54272+RND(1)*25,RND(1)*256 : GOTO 10

Is this a correct statement?

This is a correct statement but it returns the same message as jfglajda. So it is a correct statement or not?

Trivial version

PRINT "{DOWN}?SYNTAX  ERROR";

The {DOWN} character is obtained by pressing the down cursor key

Expert version

POKE781,11:SYS58251

Set the register X with value 11, then call the error routine (X=11 handles Syntax Error). Thanks to palordrolap.

Make a click sound

POKE 54296,15:POKE 54296,0

Quines

A quine is a non-empty computer program which takes no input and produces a copy of its own source code as its only output. Wikipedia

Cheating quine

10 LIST

Actual quine

1 A$="1 A$=:PRINT LEFT$(A$,5)CHR$(34)A$CHR$(34)RIGHT$(A$,49)":PRINT LEFT$(A$,5)CHR$(34)A$CHR$(34)RIGHT$(A$,49)

A shorter version of 108 chars should be retrieved by removing wihite spaces after PRINT statements and, of course, replacing value 49 with 48 in RIGHT$ statemets. Due the two line limitation of C64 editor it shall be compiled or edited with CBM Studio.

The following one may be edited directly in a real C64.

Computing PI

10 REM COMPUTING PI (NILAKANTHA SERIES) 
20 PRINT "{CLEAR}"
30 K=2: P=3: S=4
40 P=P+S/(K*(K+1)*(K+2))
50 PRINT "{HOME}";P
60 K=K+2: S=-S
70 GOTO 40

Otherwise, by cheating

PRINT {PI}

Ohterwise, a good approximation

PRINT 355/113

Hofstadter Q sequence

100 REM HOFSTADTER Q NUMBERS
110 DIM Q(1000)
120 Q(1)=1 : Q(2)=1
130 FOR N=3 TO 1000
140 : Q(N) = Q(N-Q(N-1)) + Q(N-Q(N-2))
150 NEXT N
160 PRINT "FIRST NUMBERS: ";
170 FOR I=1 TO 10
180 : PRINT Q(I);
190 NEXT I
200 PRINT
210 PRINT "1000th NUMBER: "; Q(1000)

Fibonacci Numbers

10 REM FIBONACCI NUMNBERS
20 A=1: B=1
30 PRINT A; B;
40 FOR I=3 TO 15
50 T=A+B: A=B: B=T
60 PRINT T;
70 NEXT

Memory Worm

10 POKE RND(1)*65536, RND(1)*256 : GOTO 10

Random stuff

10 P=RND(1)*1000 : POKE 1024+P, RND(1)*128 : POKE 55296+P, RND(1)*16 : GOTO 10

Timing stuff

Prints timer ticks since Power-On (1 Tick = 1/60 Second)

PRINT TIME

Prints timer since Power-On in Hour/Minute/Second Format

PRINT TIME$

The accuracy of the timer is very poor (>1% drift)

Soft reset

SYS 64738

Screen Earthquake

10 POKE 53270,200+RND(1)*8 : GOTO 10

Little Magic

10 X=RND(-42): FOR I=1 TO 5: PRINT CHR$(RND(1)*26+65);: NEXT 

output: DECKS