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Tolik

FPU detection

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Tolik    122
I know how to detect FPU, using CPUID instruction, but with instruction supports by 486DX4 or better. Anyone, know to detect FPU in older processors(386, 486SX, 486DX)?

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jenova    122
to detect the FPU on a 386/486 what you need to do is write to the FPU status register and then read the status register back.
the FNINIT and FNSTENV instructions.

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