KDJ11-A CPU

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KDJ11-A CPU

The KDJ11-A CPU board (M8192) is the first QBUS CPU card using the J-11 chip of the PDP-11; it was used in the PDP-11/73).

It contains an 8K-byte write-through cache (set size 1, block size 1 16-bit word), protected by parity; cache control logic inspects DMA transfers and invalidates cache entries for memory which is written to by a device.

It also provides a set of diagnostic LEDs, and a Line Time Clock; but no other devices (boot PROM, serial line, etc). Although the J-11 does implement FP11 floating-point, the board can use the FPJ11 Floating Point Accelerator (note that only the -YB version of the board operates correctly with the FPJ11).