24 Nov
2009
24 Nov
'09
7:28 p.m.
Tony Duell wrote:
Heh, you remind me of the computer I had on my back driveway for several
months quite a few years ago with a 23 bit word length. I doubt it was
complete, and it was part of an ill advised joint venture so the other
guy eventually took most of it away. (My wife was quite happy to see it
all go.) I did keep the programmer's quick reference card, though I
don't know where it is at the moment. I recall a fair amount of the
wiring was miniature coax, and it was a core machine. I suspect very
few were ever built. Wish now I'd kept the core stack at least. I
think I do still have the Selectric typewriter with a solenoid and
contacts kludge on the bottom that served as the console device - it was
not an I/O Selectric.
Later,
Charlie C.
I'd take
that back perhaps another 10 years to 1973. It's a little
boring seeing systems with fixed power-of-two word lengths, 8-bit
characters and predictable instruction sets, all implemented with MOS
transistors.
I have a a few machines from the early 1980s with 20 bit word length (so
not a power of 2), variable instruciton set (the microcode is loaded from
disk at power-on), and the CPU is mostly made from bipolar ICs. OK, they
do use 8-bit characters.
-tony