8 Bit Home Computer Benchmarks

Over the years I've collected quite a few 8 bit home computers. Out of curiosity I decided to write a simple prime sieve benchmark to compare their implementations of BASIC.

10 LET W=500:DIM F(W):LET P=1:LET A=3
20 LET F(P)=A:LET P=P+1:IF P>W THEN STOP
30 LET A=A+2:LET X=1
40 LET S=A/F(X):IF S=INT(S) THEN 30
50 LET X=X+1:IF X<P AND F(X)*F(X)<=A THEN 40
60 GOTO 20

Here are the results from a few of the machines I have to hand:

System	CPU	Time
Acorn Electron	2.0MHz 6502	138
Amstrad CPC464	4.0MHz Z80A	140
Commodore C64	1.0MHz 6510	254
Commodore Plus/4	1.0 MHz 8501	267
Tandy 64K CoCo 2	0.895MHz 6809E	271
Atari 800XL	1.8MHz 6502	316
Sinclair Spectrum +3	3.55MHz Z80A	388

Let me know how long it takes to run on your favourite classic computer. :-)