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Subject: [TUHS] Re: Clever code
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Hi N.,

> I had always thought of a delay line as a precursor to a register (or
> stack) for storing intermediate results.  Is this not an accurate way
> of thinking about it?

As an example, https://en.wikipedia.org/wiki/EDVAC#Technical_description
says

    Physically, the computer comprised the following components:

        - a magnetic tape reader-recorder (Wilkes 1956:36 describes this
          as a wire recorder.)
        ...
        - a dual memory unit consisting of two sets of 64 mercury
          acoustic delay lines of eight words capacity on each line
          [1 Ki words]
        - three temporary delay-line tanks each holding a single word

It looks like the three temporaries were more akin to a stack or
registers with the main delay lines providing working memory distinct
from tape storage.

Another analogy for a delay line might be a steadily turning Rolodex
where the card on display can be read and then written, perhaps with a
different value, before it disappears.

-- 
Cheers, Ralph.