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Ah yes. That's the fun thing about doing digital electronics. You can't
just *buy* a 7400. No, you have to decide whether you want a 74LS00 or a
74HC00 or a 74HCT00 or...
Reading the datasheets is like walking into another world. (Especially
since the datasheets are usually poorly-scanned grainy PDFs that don't
match the part number you actually asked about!)
However, I just found the following pages:
http://www.kpsec.freeuk.com/components/ic.htm#logic
http://www.kpsec.freeuk.com/components/74series.htm
http://www.kpsec.freeuk.com/components/cmos.htm
Suddenly everything seems so much clearer. For example...
"74LS series: Inputs 'float' high to logic 1 if unconnected."
Oh crap. Well that would explain a thing or two! >_<
(I foolishly assumed that being unconnected would register as 0V - i.e.,
logic 0. Damn, this is going to make interactive testing *so* much harder!)
Also, it's nice to have some indication of the power requirements,
switching frequencies, and what the hell all the letter codes mean!
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