Quote:
Originally Posted by Thomas Richter
The 68060 (and 68040) lacks the coprocessor interface the 68020 and 68030 had, so you cannot connect a 68882 to a 68040 or 68060. The best you could do is to connect it as an I/O device, and manually banging its interface, which requires a software interface and is going to be very slow. Talking about speed, even natively the 68882 is rather slow compared to the 68060 internal FPU.
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A custom Hardware interface for an LC060 and a 68882 would actually be quite fast. Both the CPU and FPU have 32 bit data buses and can run synchronously at the same clock speeds (approx. 50-75 MHz). It may not be quite as efficient as the co-processor interface of the 50 MHz 68030 but still fast enough to out-perform software emulation in most cases.
The real problem (again) is the exception trap overhead killing the performance. The old mathieee.resource could be adapted to support such an interface without the exception trap overhead. But (again) there are still not many applications using the mathieee.libraries.