Re: Two friendly questions to Apple II users...

[nathan@visi.com (Nathan Mates)]

In article <338196D4.241CFE9D@ensica.fr>,
Fabrice Frances  <frances@ensica.fr> wrote:
>1) I quite remember the floating point variables were 4 bytes in Apple's 
>Basic (an accuracy of about 6 and half decimals), am I wrong ? or were 
>there two Basics, one from Apple and one from Microsoft ? And the one
>from Microsoft used 5 bytes floating point values (about 9 and half 
>decimals) ?

   There were two major variants of Basic for Apple IIs: Integer
Basic, done inhouse by Steve Wozniak, and Applesoft Basic, mostly done
by Microsoft. [I think some of the hires stuff may have been finished
at Apple]. Integer Basic, as the name implies, is integers (and
strings) only; Applesoft added the ability to use reals. Those reals
use 5 bytes apiece for storing their content in memory (plus overhead
for variable names, etc, but the highest bit (sign) is expanded off to
a sixth byte when loading the floating pt accum for math stuff, if I
recall correctly).

>3) Easier: names of variable aren't limited in length but only the first
>two characters are significative... right or wrong ?

   Correct.  The significant part of variable names are of the form
[A-Z] or [A-Z][A-Z0-9], excluding 2-letter reserved words such as 'AT'
and 'TO'. Suffixes denote variable type: % for integer (stored as 2
bytes), $ for string, and nothing for reals.

>4) More technical: is there a microsoft signature in the code,
>consisting of the ascii characters !FTOSORCIM (Microsoft! backwards),

   Neat. I'll look for it.

Nathan Mates
--
<*> Nathan Mates http://www.visi.com/~nathan/      <*>
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