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>> Datasheets aren't manuals. They assume that you already know what,
>> say, a Gated D-Latch is, and that you just want to know what its
>> maximum driving current is or something. If you *don't* already know
>> what a Gated D-Latch is, the datasheet will be of no use at all. You
>> need *real* instructions.
>
> Have you ever looked seriously at a datasheet?
Gee, let me see now. I believer there are at least 4 linked from this
thread alone. So that would be, um... yes.
> Most datasheets contain a lot more information than just what it is.
> Apart from just giving the pin layout, there is the logical function
> (for logical ICs), specifications of allowed inputs and a description of
> the outputs, often for complex ICs there are also typical application
> and a small tutorial on the working of the thing.
> E.g. take http://ww1.microchip.com/downloads/en/DeviceDoc/21805a.pdf
> that covers everything from what a SAR is to an introduction to I2C.
> What more would you want from a manual that isn't included in this??
> The layout of datasheets is in general that they start with the things
> you need to know if you already know what the IC does and the later
> pages are increasing descriptive. Contrary to what you might expect, you
> as a beginner should skip the technical data and go straight to the
> later chapters in the datasheet.
The datasheet for the 7400 is 1 page. It tells you the maximum voltages
and currents, a few time constants, and that's literally *it*.
As I say, it's not a manual. It assumes that you already *know* what a
NAND gate is (which fortunately I do).
>> 2. How does it help?
>
> If you look at it you see why an open input will be seen as a logical 1.
> Assuming you know how a transistor works of course. Let me guess: you
> don't? :(
I have no idea how or why transistors work. But then, the entire _point_
of a logic gate is that it doesn't matter _how_ it works. It's a black
box. It implements a logical function. That should be all you need to know.
> Sometimes I get the impression that you employ a top-down approach to
> learning. A standard education path generally begins with the basics and
> then slowly gets to the more complicated issues. This concept is already
> very old and indeed perhaps too old and in dire need of replacement. I
> admire your attempt to revolutionize education and will be following
> this experiment with the utmost of interest.
Apparently I'm missing your point...
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