On Wed, 20 Dec 2017 13:16:12 -0500, William Donzelli wrote:
>While not an actual rotating chunk of metal ("the drum"), there were
>solid state units that certainly looked like one. The way to get high
>density solid state memory back in the very early 1970s was to use MOS
>shift registers (1024 bits on one chip!) that constantly circulated
>
Bit dropouts due to endogenous alpha particles. Ugh. No way to shield.
>the data. No random access, so if you wanted some data, you would have
>to wait for it to leave the shift register, then grab it before it
>went back in - just like the heads on a drum.
>
Such a StorageTek device (4305?) broke VM paging by being too fast. VM
didn't bother to seek sectors; it just trusted timing.
-- gil
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