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From: Joe Pfeiffer <pfeiffer@cs.nmsu.edu>
Newsgroups: comp.arch
Subject: Re: Architectural implications of locate mode I/O
Date: Thu, 04 Jul 2024 18:39:21 -0600
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John Levine <johnl@taugh.com> writes:
>
> The 709 introduced data channels in 1958 which allowed the CPU to do
> other stuff while the channel did the I/O. Wikipedia says the first
> I/O interrupt was on the NBS DYSEAC in 1954 but it's hard to see how
> an I/O interrupt would be of much use before channels. Once you had a
> channel, I/O buffering made sense, have the channel read or write one
> area while you're working on the other.

The day the CPU became faster than a teletype (or any other IO device
you care to name) interrupts became useful.  Get an interrupt saying the
teletype is ready, send a character, go back to work, repeat.