From: hilpert at cs.ubc.ca
dwight elvey wrote:
> From: hilpert at cs.ubc.ca
> ---snip--->
> Regarding the 4040, I'm speculating as I've never dealt with one or come
> across the pinout, but I suspect the 4040 essentially integrated the
> 4004/4008/4009 into one larger package making it look more like a 'standard'
> microproc in terms of signals/interface (somebody correct me if I'm wrong).
No, it was just a 4004 with, as I recall, two
more instructions.
It kept the 4004 multiplexed bus and connected to 4001's and 4002's,
just like the 4004.
As I recall, it had 4 times the address space with bank selects. I'd
need to look at the specs again to be sure.
Thanks for the correction, but why was it in such a larger package?
(4040 was a 28 or 40-pin package wasn't it?).
Hi
It had more select lines for a larger address space. I think it added
an Interupt and a single step as well. I believe that made up for the
rest of the pins. It also had TTL compatible pins for many of the signal
lines. I believe that required an extra power line as well. I recall that the
reset line had inverted logic sense but that didn't effect the pin count.
It seems the 4040 was a 24 pin part.