>> 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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