Re: wisdom of the ancients, was Architectural implications of locate mode I/O

According to MitchAlsup1 <mitchalsup@aol.com>:

S.E.L created a thing they called the RCU (Remote Control Unit).
It was basically a channel with writable microcode. NASA bought
a bunch of them because they had tapes from the deep space radio
telescopes where an entire 9-track tape contained 1 record. NASA
just started the tape and recorded satellite data until the end
of the tape, where they would start the next tape just before the
end of the previous tape.
>
So we programmed the RCU to read as much as the system memory
allowed, backed the tap up 1 second while dumping the data to
disk. Then we started the tape forward with the RCU watching
the pattern on the tape, when it detected 4096 bytes of the
last read, it would start streaming data in to memory again.
>
No other company could demonstrate that they could read one
of those tapes.
>
Presto, reading a whole 9-track tape with no inter record gaps !!

That is pretty amazing.  Did NASA have a plan for reading
those tapes, or did they not realize that normal tape units
need record gaps, or what?

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