LSI-11/2

LSI-11/2 card

The LSI-11/2 (also known as the KD11-HA) is the later type of the LSI-11 CPUs, using the same LSI-11 chip set‎. It contains only the CPU, and nothing else; it is otherwise identical in functionality to the LSI-11, including the use of ODT, and it has the same QBUS limitations as the LSI-11.

It is a dual board (M7270); it supports all the same options as the LSI-11.

These include the KEV11-A, for the EIS/FIS instructions; the KEV11-B, which provides EIS without FIS; and the KEV11-C, which provides a subset of the PDP-11 CIS (it also apparently includes the EIS, but not the FIS).

The KD11-NA is an LSI-11/2 with the KEV11-A pre-installed.

The LSI-11/2 likely also supported the optional KUV11 Writeable Control Store.

Note: The image in the "Microcomputer Products Handbook" (pg. C-18) is erroneous; the order of the chips (from the handle end) is, in fact, KEV11, Control, uROM 1, uROM 0, Data Path (per the KD11-HA print set); the order given in the Handbook is that for the LSI-11 (no doubt an image was re-used without checking).

See also

• Another LSI-11/2 - Image; also without FIS chip

Further reading

• Extended Bus Time-out Logic, MicroNote #032

External links

• Microcomputer Products Handbook - the LSI-11/2 is covered in Appendix C, pp. C-17–C-19 (pp. 609-611 of the PDF)
• M7270 LSI-11/2 microcomputer module user's guide
• ET-LSI-11 Field Maintenance Print Set (MP00706) - KD11-HA covered on pp. 131-137
• LSI-11 Processors