RM Nimbus Logo W E L C O M E
Version 3.00C

The 386 processor was never manufactured with an inbuilt Maths Coprocessor, they were seperate chips.
This board however was not supplied with the coprocessor.

This RM board was somewhat rare in that it had the ability to support 2 different types of coprocessors:

U201 = 121 Pin EMC socket for an Enhanced Maths Coprocessor, eg Weitek 386 FPU Abacus 3167

U202 = 68 Pin 80387 Processor, eg Intel A80387DX-16-33 or IIT 3C87-25

a80386DX-25 and a82385-25 on an RM Nimbus Board

After fittment of an Intel 80387

*** The Weitek 3167 is added as a mockup, however from what I can gather the 2 can coexist ***

A80387DX-22 Coprocessor and Weitek 3167
Weitek 3167

Weitek 386 FPU Abacus 3167

(Test Utility Software)


Intel i387 DX

Intel A80387DX

IIT 3C87-33

IIT 3C87



For more indepth information on a coprocessor
More information on maths coprocessor


Information on Maths Coprocessors
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