[pups] Spares, et. al for 11/44 system

[Pete Turnbull]

On Mar 7,  7:59, Gregory R. Travis wrote:

> Thought about that too but the math doesn't work.  40+64 chips = 104
> chips * 65536 bits per chip = 6815744 total bits.
>
> 6815744 doesn't divide cleanly by any of 9, 18, 19, 36, or 38

It divides by 13, though (64K x 13 x 8, so the prime factors are 2 and 13).
 Unlikely as it sounds, could this be for a 12-bit word machine?

13 is not only 12+1, it's 8+5.  5 is a common number of bits for ECC
(though not, I admit, for 8-bit words!  Usually it's 8+3, 16+5, or 16+6).

It also strikes me as odd that a NatSemi board should have TI chips on it.
 NatSemi made their own RAM, and Texas made their own PDP-11 and Vax memory
boards.

-- 

Pete						Peter Turnbull
						Network Manager
						Dept. of Computer Science
						University of York