NCR 8250 Hardware Information Required

[Aleksandrs Guba]

Is there anyone familiar with NCR 8250 Hardware and able to confirm whether 8250 had the MMU unit or not? As far as I know the 605 GPMC has no MMU circuit on the board, however, the 8250 machine operated the multi-partitioned program concurrently. Am I right that if there was no MMU, the machine might handle the partitioned program through the index register?

[wally]

You are right, the NCR 8250 had no MMU (Hardware).
Operations like that were done by IMOS (Software).
The 605 was a very modern CPU for its time and also fast.
As it is a long time ago, that is the best I can remember.
The funktions of the 605 are described in the NCR 605 TECHNICAL HANDBOOK.

http://www.thecorememory.com/NCR_605_Programming.pdf

[Matthew]

Towards the end of sales, we had a few 8270's equipped with ECC-Board here in Switzerand.