70's computers

[Paul Koning]

> On Oct 25, 2018, at 1:45 PM, Chuck Guzis via cctalk <cctalk at classiccmp.org> wrote:
> 
> On this subject, is there no interest in serial ALU designs?  At one
> time, if you wanted a low-cast implementation, that was the way to do
> it.  Also gives you a leg up on variable word-length designs.
> 
> Didn't at least one of the more popular MPU designs employ a serial ALU?
> TMS9900?

Serial ALU as a cost saver for low end makes sense in discrete transistor or early SSI machines, like the PDP-8/L.  It's hard to see how it would be useful in MPUs, given that transistors are so much cheaper there.

The other place I can think of serial arithmetic is in the Orthogonal computer architecture, sold by Sanders Associates from a 1960s invention by Bill Shooman.  That's an interesting design that does vector arithmetic row-parallel but bit-serial.  Goodyear STARAN used some of those ideas, I believe, though I know very little of the details.

	paul