On 20-5-2010 19:14, Orchid XP v8 wrote:
>>>> I think I resist any urge to comment on this. Other than "RTFM"
>>>
>>> I don't think electricity comes with a manual. Neither do ICs, 
>>> usually...
>>
>> They do, they are called datasheets.
> 
> 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?
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.


>> Have you ever looked at e.g. 
>> http://en.wikipedia.org/wiki/File:TTL_npn_nand.svg ?
> 
> 1. What is this thing?

A (simplified) circuit of an actual NAND gate (e.g. the 7400). Hint: 
read the title.

> 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? :(

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.

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