<Western Digital disk controllers are a little harder to get, so I'd
<change it to 'a disk controller of your choice' which means you can use
<an 8272 or whatever (trivial to get off an old PC card).
1793s are common enough and cheap too. If I went with the 765 (8272)
I have to claim unfair advantage!
<Considering you can make a serial port in a couple of chips, this is not
<a major design task....
But it's overhead is trivial and well enough understood as to mean little.
IT would be more of a challenge if each person supporting a processor had
to use a different one. That would be a true learning experience.
As to hardware... I cheat. I have SBCs for most common cpus.
1976 imp48 8048 (cute little sbc with tape IO, TTY, relays)
1977 8048 from byte 8048 (this was an 8035 with a mini front pannel)
1980 8051 8751 (basically a 8051 SBC with monitor)
1978 SC/mp ISP8A500 (sc/mp I)
1979 National TBX 8073 (SC/MP II with tiny basic)
1977 COSMAC ELF base 1802 (quest board)
1976 6800d1 6800
1977 kim1 6502
1983 Telvideo 905 R65c02 (card from terminal, good as SBC!)
1978 8x300 proto 8x300 (signetics)
1981 SDK78 7800 (nec propritary)
1981 78pg11 Protoboard 78pg11 (NEC propritary)
1979 Tk80 8080
1980 explorer8085 8085 (base card has 8085, ram and rom)
1980 Computime CPUZ z80 (s100 card with 1k ram, serial, eprom z80)
1981 Vt180 Z80 (z80, 64k, 4 serial, FDC, Eprom, RTC)
1981 Hurikon MLZ92 Z80 (Z80, mmu, 64k ram, eprom, serial,FDC)
1978 INtersil sampler (6100, 256w ram, rom, serial)
1982 29116 proto 29116/2911 proto for bitblitter
1982 Z8001 proto z8001 (z8001, 16k ram, 16k eprom, serial)
1982 Falcon T-11 (pdp11 chip, ram, parallel, serial, rom)
1979 SSS technico TI9900 (9900, ram, rom, serial)
1986 Advice 78032 (uVAXII, serial, 96k ram, 512k rom)
The advice was used in 87 to assist the MV2000 design!
All are classics, only the Advice wasn't available in '83.
Now if I wanted to get exotic, I have a load of 2901/2911s with date
codes pre 1980. Also 29116s (pre 83). Also enough raw 8748/9 and 8751
parts to do a major hack (maybe 50 or 60 of each). the 8749s are the
slower 1982 parts that only run at 11mhz (instruction cycle time of
1.36uS) However with the prior to 1982 limit sthere are no sortage of
choices.
I'm not above using multiple cpus to do the task or mixing several
different ones.
Allison
Received on Sat Apr 17 1999 - 22:57:21 BST