unix developed on 11/20 with 20 on panel or machine that just said pdp/11?

[ben]

On 6/20/2019 6:20 PM, Paul Koning wrote:

>> Don't you ALL wish the the 11 was 18 bits. Not looking at REAL
>> 11 but the schematic, two bits would have not been too hard to add.
> 
> You mean like a PDP-7 (the first Unix machine)?

Nope, the * PDP 11 * from 1971.

It used if I remember right a 16x1 RAM and a 1 bit ADDER was heart of 
the ALU. 4 bit wide TTL came out in the next version of the 11.
Reading the development notes for the PDP 11 (bitsavers) makes 
interesting reading on just what was planned back then.
XV6 is  teaching unix (2006) I just found out about. We now
all can upgrade from PDP11's with 56K of core to PC with 128KB of memory 
:) .
Ben.


> 	paul
> 
>