Brett (ggtgp.delete@this.yahoo.com) on January 9, 2020 12:49 pm wrote:
> Adrian (a.delete@this.acm.org) on January 9, 2020 10:51 am wrote:
> > Anon (no.delete@this.spam.com) on January 9, 2020 10:15 am wrote:
> > > David Hess (davidwhess.delete@this.gmail.com) on January 9, 2020 9:45 am wrote:
> > >
> > > > I agree that it was no coincidence but I do not think the Z80 improvements were included on the 8086
> > > > for backwards compatibility. Intel knew what they had to compete with and that the Z80 would have higher
> > > > performance 16 bit successors, which it did although way too late for IBM to consider them.
> > >
> > > Wasn't Z8000 launched before Intel 8088?
> >
> > Intel 8088 was introduced in June 1979.
> >
> > (8086 in June 1978, 8087 in 1980, 80186 & 80286 in February 1982)
> >
> > I have checked about NEC V20 & V30, they were introduced in March 1984.
> >
> > Zilog Z8000 was announced no later than March 1979, so before 8088, but that was a paper
> > launch, actual chips were available much later, maybe only in the following year.
>
> Some info on the Z8000:
> https://www.old-computers.com/history/detail.asp?n=52&t=3
> “ Despite these attractive features the Z8000 was not very fast and suffered
> from some internal bugs. It was thus never very popular and was surpassed a
> few months later by the Motorola 68000 and later, by the Intel 286. ”
>
> What were the bugs and were they ever fixed?
> There was an interview with one of the primary designers and he said he left
> because Zilog could not make working chips. Though I believe he was talking about
> the later 32bit Z80000 which used a upward compatible instruction set.
> http://www.bitsavers.org/components/zilog/z80000/Z80000_CPU_Preliminary_Technical_Manual_Sep84.pdf

Oral history of the Zilog Z8000:
https://archive.computerhistory.org/resources/access/text/2015/06/102658075-05-01-acc.pdf

The MMU chip was a year late but that was not important.
Got crushed between the 8086 and 68000 in 1979.
Did not realize that the idea of a 64k limited chip was dead and segments would not revive it.
Seat of the pants decision making.

My take, if Zilog had talked to customers they would not have made this mistake.

Still want to know what happened to the Z80000 which is listed as out in 1986.

National Semiconductor 32032 came out in 1982 and was not fixed until 1985.
https://en.wikipedia.org/wiki/NS320xx

So the virtue of talking to customers and taking longer ended up just as crushed.
Looks like being first mover(s) in silicon and software is all that matters.
Being too early and expensive can also be deadly.

The Z800 was supposed to come out in 1985, but was needed back in 1979 instead of the Z8000.
This alternate history could have split the market and have had some success, a CP/M upgrade alternative to DOS.