5 ms·

It is possible to make VM work with the 68000, Masscomp did it but it was pretty brute force, they ran two 68000's in lock step with one just behind the other

It is possible to make VM work with the 68000, Masscomp did it but it was pretty brute force, they ran two 68000's in lock step with one just behind the other so when the first one faulted it stopped the other one and the other handled the fault. Something like that. Clem Cole would know the exact details. They made for a pretty beefy machine, I ran ~20 users on one. That was when we had a pile students on a Vax 11/780, I had accounts on both and much preferred the Masscomp.

Turing_Machine 11y ago
I think there were several manufacturers who used that trick. Apollo was another. That wasn't really an option for consumer-grade machines like the Atari ST, though, since 68000 chips were pretty expensive at the time (I think they were around $500 apiece when they were introduced). By the time the price came down the later 680x0 chips with real MMUs were available.
- aswanson 11y ago
  Wow. $500 for a 68000?!
  - kabdib 11y ago
    I don't recall the COGs for the ST (they held this stuff pretty close), but in 1985, the 68000 CPU couldn't have been more than $50, probably less. Almost certainly much less because the Tramiels were absolute wizards at making deals.
    - bryanlarsen 11y ago
      1985 was 6 years after the 68K was reduced. By Moore's law, the cost of manufacturing should have been about 1/16th of what it was in 1979, so the volume price was probably around 1/16th of introduction as well.
      - kabdib 11y ago
        Remember that everything on the ST was being costed in early or mid 1984, about a year before the ST shipped. (Which in retrospect was an amazingly compressed schedule...) I think that the National 32032 would have beaten the 68K in cost; National was pretty hungry and willing to make good deals. But their chips were rather extremely very buggy (which the Tramiels may not have cared about, since making software engineers suffer was part of their model), but it was a relatively poor performer, clock-for-clock, and that made the hardware engineers go "ewwww" and after a while we software guys realized that National wasn't being invited over for meetings any more.
    - yuhong 11y ago
      At this point the 68010 had been available for a long time and the 68020 was just released. These still had no MMU but had much better bus error handling than the 68000. In retrospect, it was probably trivial to do 68000/68010 versions of the same CPU by just changing the microcode.
      - Turing_Machine 11y ago
        The 68010 and the 68020 both had (external) MMUs available. In those days, the MMU and FPU were almost always separate chips (I can't think of any exceptions, though there might have been some). Granted, the one for the 68010 sucked pretty bad.
        yuhong 11y ago
        Yes, this is exactly what I mean. There was Motorola's own MMUs, but custom MMUs based on discrete logic was also common.
  - dsr_ 11y ago
    State of the art high-speed CPU. You don't blink at paying Intel $500 for a Xeon 10-core doohickey, right? And like everything else in silicon, sizes went down, production went up, costs went down. The Palm PDAs used, essentially, 68030 at 33MHz (a variant called Dragonball) and started selling at $499 for the system and were eventually around $79 each. Now a slow, small Raspberry Pi runs $5, plus $25 in more or less required accessories.
  - protomyth 11y ago
    This is why I wished the 6502 crew had followed up with a processor. This price and Intel pretty much killed any 16-bit or 32-bit follow-on to the under <$200 market after the C64 / Atari 8-bit era. For some real joy, check the 88000 pricing and see why it failed.
    - happycube 11y ago
      ARM's the closest spiritual successor I can think of, but it didn't have the kinda traction to make a proper successor to the cheap micros... ... at least then. now, there are. :)
- davelnewton 11y ago
  They must have lost a lot of money on the ST, then, mine cost $800 new (monochrome) IIRC.
  - Turing_Machine 11y ago
    As others have noted, the ST came out several years after the 68000, so the price had dropped some. It still was a non-trivial amount, though. The comparable Apple machine (monochrome, 68000 processor, 512K RAM) was selling for $2,800. Even given Apple's famously high margins and Jack Tramiel's equally famous "deal-making ability" (which some would call "gouging" :-)), it's clear that the ST retail pricing was pretty close to the bone.
    - jacquesm 11y ago
      As was the workmanship on some of them. I had to re-solder more than one joint on the ST's passing through one of the stores in Amsterdam (ditto for the C64 by the way). The ST was a very capable machine built on a very small budget. Compared to that other el-cheapo 68K of the time (the Sinclair QL, a 68008 based machine) it worked wonders and it was the first 32 bit capable machine that I could afford.

Turing_Machine 11y ago

I think there were several manufacturers who used that trick. Apollo was another. That wasn't really an option for consumer-grade machines like the Atari ST, though, since 68000 chips were pretty expensive at the time (I think they were around $500 apiece when they were introduced). By the time the price came down the later 680x0 chips with real MMUs were available.

aswanson 11y ago
Wow. $500 for a 68000?!
- kabdib 11y ago
  I don't recall the COGs for the ST (they held this stuff pretty close), but in 1985, the 68000 CPU couldn't have been more than $50, probably less. Almost certainly much less because the Tramiels were absolute wizards at making deals.
  - bryanlarsen 11y ago
    1985 was 6 years after the 68K was reduced. By Moore's law, the cost of manufacturing should have been about 1/16th of what it was in 1979, so the volume price was probably around 1/16th of introduction as well.
    - kabdib 11y ago
      Remember that everything on the ST was being costed in early or mid 1984, about a year before the ST shipped. (Which in retrospect was an amazingly compressed schedule...) I think that the National 32032 would have beaten the 68K in cost; National was pretty hungry and willing to make good deals. But their chips were rather extremely very buggy (which the Tramiels may not have cared about, since making software engineers suffer was part of their model), but it was a relatively poor performer, clock-for-clock, and that made the hardware engineers go "ewwww" and after a while we software guys realized that National wasn't being invited over for meetings any more.
  - yuhong 11y ago
    At this point the 68010 had been available for a long time and the 68020 was just released. These still had no MMU but had much better bus error handling than the 68000. In retrospect, it was probably trivial to do 68000/68010 versions of the same CPU by just changing the microcode.
    - Turing_Machine 11y ago
      The 68010 and the 68020 both had (external) MMUs available. In those days, the MMU and FPU were almost always separate chips (I can't think of any exceptions, though there might have been some). Granted, the one for the 68010 sucked pretty bad.
      - yuhong 11y ago
        Yes, this is exactly what I mean. There was Motorola's own MMUs, but custom MMUs based on discrete logic was also common.
- dsr_ 11y ago
  State of the art high-speed CPU. You don't blink at paying Intel $500 for a Xeon 10-core doohickey, right? And like everything else in silicon, sizes went down, production went up, costs went down. The Palm PDAs used, essentially, 68030 at 33MHz (a variant called Dragonball) and started selling at $499 for the system and were eventually around $79 each. Now a slow, small Raspberry Pi runs $5, plus $25 in more or less required accessories.
- protomyth 11y ago
  This is why I wished the 6502 crew had followed up with a processor. This price and Intel pretty much killed any 16-bit or 32-bit follow-on to the under <$200 market after the C64 / Atari 8-bit era. For some real joy, check the 88000 pricing and see why it failed.
  - happycube 11y ago
    ARM's the closest spiritual successor I can think of, but it didn't have the kinda traction to make a proper successor to the cheap micros... ... at least then. now, there are. :)
davelnewton 11y ago
They must have lost a lot of money on the ST, then, mine cost $800 new (monochrome) IIRC.
- Turing_Machine 11y ago
  As others have noted, the ST came out several years after the 68000, so the price had dropped some. It still was a non-trivial amount, though. The comparable Apple machine (monochrome, 68000 processor, 512K RAM) was selling for $2,800. Even given Apple's famously high margins and Jack Tramiel's equally famous "deal-making ability" (which some would call "gouging" :-)), it's clear that the ST retail pricing was pretty close to the bone.
  - jacquesm 11y ago
    As was the workmanship on some of them. I had to re-solder more than one joint on the ST's passing through one of the stores in Amsterdam (ditto for the C64 by the way). The ST was a very capable machine built on a very small budget. Compared to that other el-cheapo 68K of the time (the Sinclair QL, a 68008 based machine) it worked wonders and it was the first 32 bit capable machine that I could afford.