Sam wrote:
The 4040 was actually very different from the 4004.
The 8008 is closer in
architecture to the 4004 than the 4040. The 4040 was actually a very
different design from the 4004.
Not really. The 4040 was just an improved 4004 with more registers, a few
more instructions, and a few more select lines (so that it could address more
memory).
The 8008 was quite different than the 4004 and 4040. The 4004 and 4040 have
a more elegant architecture in some ways, such as the organization of the
general registers, but the 8008 wins in others, such as the single flat
address space.
The 8080 is fairly different than the 8008. Aside from using the same names
for the registers, there's not that much similarity.