Re: RFC : SOME IDEAS FOR THE APPLE II FPGA'ers

["Michael J. Mahon" <mjmahon@aol.com>]

John B. Matthews wrote:
> In article <1herr66.1so9jr81ndbcbgN%bieling@terra.es>,
>  bieling@terra.es (Jorge Chamorro Bieling) wrote:
>
>
> > But I'd like to be able to know *exactly* how many cycles does a certain
> > piece of code take to execute. You never know for sure when it's being
> > cached. I would be better to count on fixed, known and fast memory
> > cycles, this is the true Apple II style... isn't it ?
>
>
> I recently dusted off some EDASM documentation:
>
> http://www.wright.edu/~john.matthews/a2/rel.html#tblb1
>
> The directive "LST cyc" adds a cycle count to each line of the listing. 
> I haven't checked it for accuracy (page crossing, etc), but it looks 
> right.

Merlin also has this.

In practice, I find it of limited usefulness because of conditional
branches and page crossings, etc.  You still need a pencil and
paper, but the cycle listing annotations can save a little time.

-michael

Music synthesis for 8-bit Apple II's!
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