FP780 Floating-Point Accelerator

The FP780 Floating-Point Accelerator was an optional floating point accelerator for the VAX-11/780's KA780 CPU; the floating point instructions were performed by the microcode when it was not installed. It was installed in slots 24 through 28 of the CPU's backplane.

Implementation

It was implemented on five hex cards:

Slot	Board	Acronym	Function
24	M8285	FNM	Normalization and fraction division
25	M8286	FMH	Fraction multiplication (most significant bits)
26	M8287	FML	Fraction multiplication (least significant bits)
27	M8288	FAD	Fraction addition and subtraction
28	M8289	FCT	Exponent manipulation and FPA control

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