FP11-A Floating-Point Processor

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FP11-A floating point card

The FP11-A Floating-Point Processor is the optional hardware floating point unit for the PDP-11/34A (KD11-EA CPU). It supports the full PDP-11 FP11 floating point.

It consists of a single hex board, the M8267. Its connections to the KD11-EA include two over the back connectors; a 20-pin connector to the M8265 card of the KD11-EA, and a 10 pin connector to the M8266 card. (This was because the PDP-11/34 could be field-upgraded from a KD11-E CPU, which did not support the floating point unit, to a KD11-EA, which did - but the original DD11-P backplane was retained.)

The latter over-the-top connector uses the connectors on the M8266 card which normally hold the maintenance cables to the KY11-LB Programmer's Console; in systems with a KY11-LB, the cables to the console will now connect to the M8267 card. (This is all necessitated because the FP11-A needs access to signals carried over the maintenance cables.)