Happy Birthday VAX 11/780 (influence of)

Tony Duell ard at p850ug1.demon.co.uk
Fri Oct 29 16:16:30 CDT 2010


> I have not seen anyone comment any of the other things I listed as 
> possible firsts on the PDP-11.
> Can anyone come up with an earlier machine that used condition codes?
> How about general registers with addressing modes, which is totally 
> orthogonal? How about having the PC as a general register?

The Philips P800 series has the PC as a general register (register 0).
There are 16 registers, some instructions can only use the first 8, others
can use all 16. Addressing modes (simpler than the PDP11, I admit) are 
pretty much orthogonal.

I am not sure wheterh the PDP11 or P800 was first,m they both appeared in 
1970 I beleive.

What do you mean by condition codes here?

-tony



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