Well let me see now... I bought a couple of switches and resistors, and 
spent the morning soldering them together. I now have two switches - a 
rocker switch and a push switch. In one position, you get logic 0, in 
the other position, you get logic 1, and no floating inputs. Yay, me!

It's kind of frustrating how many problems I'm having with this whole 
exercise - and most of them aren't electrical. They're mundane physical 
issues. (E.g., one of the switches I bought has metal terminals with 
small holes to poke the wires through. Except they're too tiny to poke 
any wire through!)

Still, it was gratifying to flick some switches and watch an LED light, 
correctly implementing the truth table of a NAND gate.

I was about to try rigging up a simple binary half adder - and then I 
realised that this requires 7 NAND gates, and I obviously only have 4. >_<

I've bought a small plastic box, and I'm hoping to somehow mount some 
switches on it, common-up the power rails, and end up with a box which I 
can just connect to the power and have a nice set of output wires. But 
this requires drilling and soldering and all sorts.

It's times like this where I miss my old electronics kit. :-( Everything 
seemed so much easier back then...

-- 
http://blog.orphi.me.uk/
http://www.zazzle.com/MathematicalOrchid*

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