+---------------
| (e-mail address removed) says...
| > The little lost angel wrote:
| > > Isn't this like taking double/quadruple pumped bus and pipelining to
| > > the extreme?
| >
| > No. Not at all. As I said in another post, my proposed device is
| > completely serial except for the frequency. It uses "parallel hz" but
| > in terms of everything other than frequency, it is totally serial and
| > non-parallel. Only the clock rate is parallel.
|
| Ah, a PDP-8i. (Serial ALU in a parallel computer).
+---------------
You're thinking of the PDP-8/S ["S" for "Serial"].
*Horribly* slow, its main claim to fame was being the first
general-purpose computer to sell for $10,000. The PDP-8/I,
introduced just a couple of years later, had all the speed
of the "Classic" PDP-8 with a price only slightly higher
than the -8/S [and the PDP-8/L was even cheaper]. See:
http://www.faqs.org/faqs/dec-faq/pdp8-models/
The PDP-8/I was fully-parallel, just like the PDP-8, except
that it was the first of the "-8" line to use TTL logic levels
(+3V & 0) instead of the negative ones (-3V & 0) used in the
Classic -8. [It was built out of "M-Series" modules, rather
than the "R/S/T/B-Series".]
Note that the PDP-8 series *did* have a multi-phase clock --
four "TS1-4" clocks (or phases) and four much-shorter "TP1-4"
pulses that overlapped the transitions between the TSn phases.
The TSn phases were generally used as "enables" of some kind,
and the TPn clock pulse that terminated the phase of the same
number were generally used to clock the results of the phase
into some register. In the PDP-8/E (another TTL machine) at least,
the TSn/TPn clocks were generated from a ring or "Johnson" counter,
what today we'd call a "one-hot state machine", running at 20 MHz.
[And, yes, I know the difference between a ring counter and a
Johnson counter -- ISTR that some members of the PDP-8 family
used one and some used the other.] In the PDP-8/E, a normal
instruction took 1.2us or 24 ticks of the ring counter, but
the ring had alterate "sidings", if you will, that permitted
read/modify/write memory cycles to take 28 ticks, or 1.4us, and
extended one of the phases (TS3? TS4?) so that the incremented
[or otherwise modified] results had time to propagate to the bus.
So in a sense, it's probably legitimate to say that the PDP-8
series did use a simple form of the OP's "parallel Hz" clocking.
-Rob