29 Jan
2010
29 Jan
'10
8:04 p.m.
On Jan 28, 2010, at 11:23 PM, Ben wrote:
Whoa! Mirrored.
16 bits, actually. The two MMU architectures extended that to 18
and 22 bits. I wouldn't call it a goof considering the first one
came out in 1970. For a small lab minicomputer in 1970, 64KB isn't
bad at all.
It'll do a
good bit more than that. My high school used a UniFLEX
system
that was a 2MHz 6809 with about a dozen 1200-baud terminals. It
was used
to teach Pascal. Interactive performance was typically pretty good.
The Missing 6809 UniFLEX Archive
http://www.rtmx.com/UniFLEX/index.html
This needs to mirrored. And you do
realize "PDP-11" spanned some two and a half decades
and more
than a dozen implementations with a huge range of processing power
ranging from "wimpy" to "big clanging brass balls", right?
Yes, but the PDP 11 was designed to have raw power from the original
design. OK, they goofed on a basic address space of 18 bits. The 68000
comes close in design but offhand I still think the 68000 had only
16 bit addressing*. I do know it took a few revisions of the chip
to get
a MMU for it. By this time I moved from a COCO II to a PC clone
and never got to play with well designed chips.
You did that to yourself, man. ;) And who on this list only has
one computer?
-Dave
--
Dave McGuire
Port Charlotte, FL