[Coco] Re: Disk Basic and 512 byte block floppies.

Theodore Evans (Alex) alxevans at concentric.net
Sun Jan 18 23:07:24 EST 2004


On Jan 18, 2004, at 5:47 PM, John E. Malmberg wrote:

> Theodore (Alex) Evans wrote:
>> On Jan 18, 2004, at 5:07 PM, John E. Malmberg wrote:
>> You are right about the problem.  I would have solved it with POKE 
>> DO+3,S/SS and POKE DO+3,S/DS
>
> The result would depending on rounding.  Would .5 be interpreted as 0 
> or 1 after the conversion?

Unfortunately it would be stored as 0, so it would fail.  Your solution 
was better.

> I do not think that would be reliable because the floppy could be 
> blank on that track.

Since this whole think depends on writing to formatted floppies, there 
will be data there.  The complement is a way to make sure that the end 
is detectable no matter what the data in the sector is.




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