Re: Apple II in Scientic American

["anoneds@netscape.net" <anoneds@netscape.net>]

Roger Johnstone wrote:

>
> The chart may be right if it's just comparing speed in instructions
per
> second. That's why I think the C64 is in the right position. A 6502
> instruction takes between two and six cycles to execute. At 1MHz that

> gives a 'thoretical peak' speed of 500000 instructions per second.
The
> Apple II should be in the same position, as should the original IBM
PC
> since from memory the 8088 took a minimum of eight cycles for each
> instruction.
>
> Of course measuring the speed of a CPU by the rate of instruction
> execution is pretty meaningless, since it doesn't take into account
how
> many actions the instruction is performing or how much data it's
moving
> around.
>

No way should they be that close to a Vax 11/780. If I could only
remember the MIPS numbers from my old XT, although it was 8mhz. It
screamed compared to an Apple II or a C64. And still we had PDP 11/70s
and 11/44s at work that would kick it's butt... and the VAX 11/780 was
at least as fast as these.

Ben