64E4 - MOS technology 32 bit 68K competitor?

[Hattig]

The Z80 is still used today and was used in some popular video game machines.  Compare the ability of the 6510 to the Z80 and you have your competition.  If you are selling Commodore computers with a 6510 chip then your competitors know there is a market and anyone wanting to bring the competition can do so with a Z80 because it can do as much or more.  The Z80's clock speed today is up to 50MHZ.  The reason you can't speed up the 6502 is because it has multiple clocks so the Z80 would have won out if there was competition on power.

Both the Z80 and the 6502 (and derivatives like the 6510) were decent designs. The Z80 had higher clocks, but a lower instructions per clock. Overall a 4MHz Z80 and a 1-2MHz 6502 performed the same.

The problem was that for a long time, the 6502 stayed at 2MHz max, and additionally the C64 kept on using a 1MHz 6502. The Z80 got a B revision at 6MHz - not that it was used much.

Overall home computers in most of the 80s were in stasis - not continually improving. MOS could have done a new 6502 running at a higher speed, but they didn't for quite some time - and then they lost it all because companies started sourcing them from other sources who did put the work in to improve the design.

Note the C65 was meant to have an up-to ~8MHz 6502 derivative.

[Hattig]

In any case, psxphill is right; CP/M was pretty nearly dead by 1985, having been supplanted for business use by MS-DOS, and never really catching on with most Z80-based home computers the way it did with the hobbyist micros of the late '70s.

I wouldn't be so sure of that - in the US maybe, but in the UK CP/M was kept alive for a long time because of the Amstrad CPC 6128 and the very popular Amstrad PCW series.  However CP/M was never really advertised as a key feature, it was just a capability the machines came with and that users could use.

[Hattig]

A Raspberry Pi is $35, a C64 + a 1541 would set you back by about $1000. Do you really think people would buy another one because the floppy drive was faster?

The C64 is the best selling personal computer of all time. Commodore did pretty well without you.

Heh, $1000 in 1982 dollars is $2,385.71 today. Puts that $35 RasPi + $5 (SD card) + $10 (case) + $20 (keyboard, mouse) into perspective.

And one of the reasons the C64 did well was because it was cost reduced and kept the same - compatibility, large back catalogue, rapidly dropping price - that means success.

[Hattig]

65c02 is available up to 200mhz.
 
http://www.westerndesigncenter.com/wdc/
 
They are probably using FPGA.

In addition it looks like the eZ80 hasn't really been updated since 2001, Zilog just have it as a cheap money-making product that tops out at 50MHz - although the IPC is up to 11 times higher than the original Z80.

I guess that it's simply not worth it to improve these products any more, not with ARM Cortex M series hanging around for applications that need more oomph than an eZ80.

[Hattig]

No.  I would have demanded changes for the 1541 back then.

1541 worked. Slowly, but it worked.

A fix could have taken some time, that's time you're not making money. So you should release the slow, but working system.

The fix should still have been done, resulting in a 1542, and possibly a fixed C64 if that side of things also needed fixing. Not ideal, but technology marches on, and it wasn't long before the slow disc drive was a bit of a laughing stock.