Looks like they were still making (or perhaps still are) 68882's:

Link

If you see that image it has the Freescale logo!

You would have thought that most commercial purposes for 68K chips would have been achieved with 3.3v 68060's, negating the need for these co-processors.

Thoughts?

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Amiga A1200, 3.1 ROMs, Blizzard 1230 MKIV 64MB & FPU, 4GB DoM SSD, Workbench 3.1

@A1200

From the 68020, 68030, 68040 and 68060 there is the capability to use up to 8 different "Co Processor" chips...

the 68882 is an Asynchronous FPU using this Protocol and can be wired to respond to any "Co Processor ID" using the selection wiring...

the 68851 responds as Co-Processor 0 (this is internal on the 040 and 060 chips making this ID "used") originally being used for the 020 and I am unaware of any 030 designs using this (my knowledge does have its limits)

the Internal FPU on the 040 and 060 is able to be bypassed using the "cpXXXX" access to the co processor protocol so it is perfectly legitimate to actually have 6 additional external FPU modules in addition to the internal MMU and FPU already within the 040 and 060...

so it is still valid to have the 68882 manufactured for use with the 68060 production.

this protocol is also openly described in the Motorola-SPS / Freescale Semiconductor literature about the 680x0 series (in the User Manuals for the 020 and later processors) which allows for anyone who is capable enough to program their own co-processor to respond properly and support special instructions.

does this help?

@Belxjander

Very interesting my friend. Yes that is certainly useful. I didn't know that the 040/060 could run external FPUs and 8 at that. Woah, I wonder what the bottleneck would be there. The clock, the interrupts? Seems amazing. I would like to see such a system running and get some benchmarks.

I am a big fan of the 68030 for the reasons of Amiga compatibility vs. the better performance not to mention the great price point. I wonder what capabilities this has in terms of clever stuff? As far as I was aware the 020 and 030 are very similar except there are some more instructions and the MMU on board (on the full versions). The 030 doesn't have an internal FPU as you say.

All interesting stuff. Any more?

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Amiga A1200, 3.1 ROMs, Blizzard 1230 MKIV 64MB & FPU, 4GB DoM SSD, Workbench 3.1

@A1200

That is pretty much all I remember... it is all best explained in the "680x0 User Manual" series of books if you can find yourself a copy of them all...

parts are in the "Programmers Handbook" and parts are spread amongst the various User Manuals

@A1200

Given that the internal FPU in the 040 is about 10 times faster than an external 68882 I would say it doesn't make a whole lot of sense unless it's used to run the missing opcodes which would otherwise be emulated. And even then I'm not sure how useful it is.

But for an 030, having up to 7 FPUs should certainly be considered

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This weeks pet peeve:
Using "voltage" instead of "potential", which leads to inventing new words like "amperage" instead of "current" (I, measured in A) or possible "charge" (amperehours, Ah or Coulomb, C). Sometimes I don't even know what people mean.

@olegil

Tanks for putting it Down to earth before ... Y know what..