🚀 go-pugleaf

khorton@tech.iupui.edu (Kevin Horton) writes:

>-> CMOS? The C128 is pure NMOS...
>
>Are you sure?

Yes, I am absolutely sure.

>I was sure that the 85 series was CMOS, while the 65 series was
>NMOS.  Why the diffrence between the 6581 & the 8580?  I have a 6582 that is
>NMOS and runs on 9V, altho the 9V section takes very little current, compared
>to the 6581 which takes 40ma or so at 12V.

85xx ICs were made using enhanced NMOS technique. That's just a different
manufacturing-process.

That does not mean that the 85xx series is functionally superior to the
65xx series. While the 85xx series was produced CBM still made some new
revisions of the 65xx series. A famous example of this is the 6569R5,
which is the only known bug-free PAL VIC-II. The 8563 series of this VIC
was derived from 6569R3 and so it has the same old bugs. An infamous
example is the 6582 as you mentioned, there they messed up the chip while
"improving" it.

>Maybe they picked up revision numbers where they left off on the 6581?

It seems so, but they have not done this to the VIC-II, there they went
from 6569R3 to 8563R2.

>The 6582 needs a diffrent cap than the 6581; it's something like .12uf
>compared to the .0012 uf or so on the 6581.   I do know that the 6582
>screws up many effects.  It drops out and clicks/pops on certain songs,
>making them un-listenable.  Most notable is Hubbard's _Delta_.

That's the reason why I collected several 6581 - for clear sound even in
the next century. :-)

>If anyone has a 8580 they don't want or need, I'll trade one for any 2 commie
>chips I have.  I have 6510's, ROMs, and maybe a few CIAs.
>
>I'm also trying to find an 8500.

I've got 2 C64s using the 8500, but there is absolutely no difference to
the 6510! The ICs are fully interchangeable.

MfG Andreas