Re: Help with confirmation on a small bit of assembly?

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

aiiadict@gmail.com wrote:
> mdj wrote:
>
> > Relax Tristan, this is *the* most common mistake made by programmers,
> > of all levels of experience. It's some kind of brain failure mode than
> > causes humans to equate the number of digits in a number system with
> > highest value digit.
>
>
>   I poke around with 6502...  made the mistake of thinking calling
> prodos read command with FF as number of requested bytes would
> get me 256 bytes from the file..
>
> 8 bits can represent 256 values...  one of them being ZERO
>
>
> why would you want to read 0 bytes from a file?

You probably wouldn't, but ProDOS also returns the *actual* number
of bytes read after each request, and *that* result might be 0.

In NadaNet, each data packet is 1..256 bytes long, so 0 *does*
mean 256.  ;-)  Of course, the same applies for many loops counted
in a single byte.

-michael

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