MITS 2SIO serial chip?

From: Peter C. Wallace <pcw_at_mesanet.com>
Date: Mon Dec 17 11:19:53 2001

On Sun, 16 Dec 2001, Richard Erlacher wrote:

> see below, plz.
>
> Dick
>
> ----- Original Message -----
> From: "Peter C. Wallace" <pcw_at_mesanet.com>
> To: <classiccmp_at_classiccmp.org>
> Sent: Sunday, December 16, 2001 4:12 PM
> Subject: Re: MITS 2SIO serial chip?
>
>
> > On Sun, 16 Dec 2001, Ben Franchuk wrote:
> >
> > > ajp166 wrote:
> > > > PALS are 1970s technology, really old to some of us.
> > > Arg! And here I thought the 8008 was 70's technology.
> >
> > Well more into the 80s since the PAL was invented in 1978...
> >
> I've stumbled over a 1978 databook from MMI this weekend a couple of times, that
> suggests the 16L/R/X/A series is new product in 1978, but there were quite a few
> PALs that predate them. Signetics had a different sort of device than MMI, that
> also goes back to the '70's.

There were earlier programmable logic parts, but the PAL was invented in
in 1978 by Birkner and Chua...

> > >
> > > > Actually thats not true. BY 1981 you have peripherals in the 125ns read
> > > > write timing range. Then again Z80 at that time was just hinting at 6mhz
> > > > so z80 peripherals were of an according spped for that cpu. However,
> > > > other
> > > > parts were faster and often far cheaper.
> > >
> > > If you must know it is a floppy disk controller I need. Right now
> > > I plan to use WD2797 floppy disk controller. I would love to use
> > > a newer chip,but I can't find any! I want to stay with DIP's and PLCC's
> > > here. This may be the 21 century but my soldering skills are the 19'th.
> >
> > Actually Its possible to do QFPs pretty easy with just a good soldering
> > iron and lots of flux... Even BGA's aren't too hard with a hot air gun
> > (surface tension does the work)
> >
> > >
> > > > Personally if I wanted the SIO functionality for a NON-z80 system I'd
> > > > never use the zilog part. Reason it was not cheap,nor was it easy to
> > > > use for non-z80 systems. They were designed for the Z80, period.
> > > > Unfortunatly they were slow. If you wanted faster the 83xx or 85xx
> > > > parts from Zilog were a far better choice but Zbus was scary to most
> > > > people and they weren't cheap. The other part of this is NEC and
> > > > Intel did the MPSC (NEC D7201, Intel 8274) which was functionally
> > > > identical to the SIO and was "tuned" for 8080/8085/8088/8086 style
> > > > busses and faster as well. It was a more generic part than the SIO.
> > > > Also around that time Signetics and friends were doing the 2681 part
> > > > that was cheap and available in various flavors. Peripherals back then
> > > > were quite varied.
> > >
> > > I still favor the simple dumb uart chip. TR1602?. I like things than
> > > you hit reset, it starts ... not like the classic star-trek computers
> > > that always go down. Usually when you need them.
> >
> I always liked them, too, except for the space they required, including the
> external clock generator(s).
> > > --
> > > Ben Franchuk --- Pre-historic Cpu's --
> > > www.jetnet.ab.ca/users/bfranchuk/index.html
> > >
> >
> > Can you still get TR1602's? I remember building something with them (maybe
> > it was a 1402) and 3341 FIFO's in the 70's
> >
> I remember an ad not long ago that listed, among other things, the 1602. I've
> not seen the 3341 for quite a long while, since there are CMOS versions.
> >
> > Peter Wallace
> >
> >
> >
>
>

Peter Wallace
Mesa Electronics
Received on Mon Dec 17 2001 - 11:19:53 GMT