Re: Macintosh LC...need info on this =) TIA

[Roy and/or Janet Miller <millers@inetnebr.com>]

Matt Jenkins wrote:

> Roy and/or Janet Miller <millers@inetnebr.com> wrote:
>
> > No Matt, I meant 16/32. The 68000 had a 16 bit data bus, as the 8088 had an 8 bit data bus.
> > The 68000 had 32 bit registers (with, as you mention, a 24 bit address space) while the
> > 8088 had 16 bit registers with a 20 bit address space. In a similar fashion the 386SX was a
> > 16/32 chip: 16 bit data bus, 32 bit registers, 24 bit address space.
>
> While this is true, it's only important in a physical sense. All of the above mentioned chips
> have this limitation, but it only affects performance, not functionality.
>
> Besides, I've never heard anyone imply the 65816 is an 8 bit chip.

If you've read the literature from the early to mid 80s, (Byte, PC, Personal Computing, Computer
Shopper, etc.) there were a number of arguments on this issue. Is the IBM PC a 16 bit machine,
because the 8088 was 16 bit internally, or is it an 8 bit machine because it was 8 bit outside
the 8088, including the data bus? So the 8/16 or 16/32 was used to designate these kind of hybrid
chips. I do remember complaints against Radio Shack for calling the 68E09B (used in the CoCo 3)
an 8/16 chip because, like the 6502, it had a 16 bit address bus (I seem to recall that  there
was also another register or a way to use two 8 bit registers as one 16 bit). In reference to the
65816, by the above convention, it is an 8/16 bit chip, like the 8088, but as we all know, it has
a 24 bit address bus, like the 68000 or the 80286 and the 80386SX. Perhaps we could call it an
8/16/24 bit chip?

Roy

>
>
> --
>               Matt(hew) Jenkins. Computer Science (RMIT Bundoora)
>                            email: mdj@cs.rmit.edu.au
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