12 Jun
1998
12 Jun
'98
1:37 p.m.
Because if I use a baby AT case, it will take less space than the
apple case. I will also be able to stick the floppy drive inside.
Why?
<keyboard is external anyway. But I was reading the CP/M manual
<(pretty shallow), and it mentions a 16-user capability and password
<protection.
Well the 16 user thing is not multiuser it's a way of diving up the
directory into 16 distinct areas as CP/M didn't have subdirectories.
Password protection? There wasn't any as part of CP/M.
The CP/M 3+ manual says
the syntax is drive:12345678.123;password.
Maybe it's a weird DR thing. They tended to add weird stuff...
<say that the Z-80 was better than the 8088? It was
certainly used
<much more...
Better... that's a relative term. It was cheaper to use, more software
available as it was fully upward compatable with the 8080 (and 8085)
that preceeded it and it was there before the 8088. Also as the 8088
got faster the z80 also got faster and added a MMU. I can still build
a system using z80 for less than the 8088 and the z80 one will be
easier
to program. If the program gets larger than fits in
the 64k space then
the competition becomes a bit more fair. Still segmented space is
pretty
ugly and a paged MMU on z80 is very easy to do. Or
better yet a z180
(64180) which is a z180 with MMU, 2 serial ports and a DMA all on one
chip (and still cheaper and faster than a bare 8088 in 1985). The
z180
also offered something the 8088 line never had which
was a compatable
highly integrated version as the 8088 needed several parts around it to
use effectively and the '188 was an odd duck compared to the 8088. So
for the 8088 comparison the z80 was hard to dislodge. It really took
the
386(32bits) to make a real impact.
Z80 space was characterized as developing, it was inexpensive to
develop
around, there were lots of similar and competing
systems (both
a blessing and curse), tons of cheap to free software, offered
sufficient
compute power and friendy to program in assembler. The
only other chip
to be as persistant, easy to use and popular was the 6502.
I might add that both were quite popular in the instrumentation and
control sytems field.
Tidbit... the z80/z180 is still in production and the cmos z80s182 runs
at a screaming 20mhz internal clock (roughly 2-4mips processing speed)
and can come to a complete stop, using only microwatts of power in that
mode. I have a z180 at 9.8mhz and it's quite fast for text apps and is
usually waiting on the SCSI hard disk system (xybec/st251).
Allison
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