A Technical History of Apple's Operating Systems

[Dave Dunfield]

> > > Although according to the author the 6502 can address 65K, not 64K.
> > 
> > This is very common, and is based on an assumption of 'k' meaning
> > 1000 (decimal), not 1024 - 16 bit bus - 65535 bytes (65 thousand).
> 
> Dave,
> 
>  I hate to be a picker of nits, but you forgot byte 0...  
> So there is actually 65536 bytes of memory but the last byte is 
> at address 65535 or $FFFF.

Of course
I actually intended to type 65536, but my fingers automatically rounded
this down to  valid 16-bit number :-)


> > I've seen it in data sheets and other reasonably technically accurate
> > material - I guess it depends on your point of view (and how low-level
> > your experience is :-)
> > 
> > Hard drive manufacturers have been doing the same thing with "meg"
> > for years - specing in decimal 1,000,000 makes the drive sound bigger
> > than specing in 2**20 sized blocks.

>  I really think this is a very silly practice...  Imagine 
> what would happen if they did that with RAM sticks?!

In a way it makes sense ... The general public understands "thousand"
better than "k", so giving them the number of bytes in thousands will
give them a better idea of the actual number than a true "k" value
would - we computer geeks just think differently than everyone else
I find myself counting non-computer related things in hex all the time
 (If you are doing it out loud, people nearby look at you strangely
  and move slightly further away)

Dave

--
dave06a (at)    Dave Dunfield
dunfield (dot)  Firmware development services & tools: www.dunfield.com
com             Collector of vintage computing equipment:
                http://www.classiccmp.org/dunfield/index.html