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Im Gegensatz zu späteren Coprozessoren, wie dem 80287, musste der 8087 mit identer Geschwindigkeit wie die CPU laufen

It worked in tandem with the 8086 or 8088 and introduced about 60 new instructions. Most 8087 assembly mnemonics begin with F, such as FADD, FMUL, FCOM and so on, making them easily distinguishable from 8086 instructions. The binary encodings for all 8087 instructions begin with the bit pattern 11011, decimal 27, the same as the ASCII character ESC although in the higher order bits of a byte; similar instruction prefixes are also sometimes referred to as "escape codes". When the 8088 saw the escape code, it would defer to the 8087 until it was ready.

The 8087 was, in theory, capable of working concurrently while the 8086/8 processes additional instructions. In practice, there was the potential for a bus crash if both processors attempted to access either bus simultaneously. The assembler would automatically insert an 'FWAIT' instruction after each and every coprocessor opcode forcing the 8086/8 to halt execution until the 8087 signalled that it had finished.[14] This limitation was removed from later designs.

matze79 hat geschrieben:Also wenn das BIOS FPU vorhanden meldet wirds nicht gehen.