Yes I think it might eventually look just like that!altough mine has more switches (either because it has more functions or because I can not grasp how a (de)Multiplexer works, probaly the latter
I'll make sure I'll post all the schemtacis here and since I have to bundle it all neatly for school why not post it here. Shortly said: you will be able to refer to my computer (if i can get it to work) for the moment however type (without quotes) "magic-1 CPU" you'll find a very informative site there and more important, in the bottom there is a WebRing so all CPU project sites are linked (i'll guess I'll add mine once it is done)!
ooh one more thing my 'coach' for this project showed me a very simple Relay adding machine it used (i am writing from memory now so bare with me) 14 double switch relays and can add up to 9+9 (it has 5 output leds so it could output to 32 theoretically).
To add even further to an unorganised post, I finally understand the carry bit now! What I understand it to be is that it is a one bit short term memory.
if we add 01 and 01 in binary we get 10, lets have a look at that further:
lets do this bit by bit:
0+0 = 0
1+1 = 0 BUT "carry" a 1 to the next (More significant) bit.
BUT remember (in the carry bit) a 1
Carry = 1
So we get:
10 this is the carry bit I have been talking about all the time!
Which makes it:
these are the same! (if you cant see it just figure it like this, the one next to the "<--" drops down by sheer gravity into the "(1)" )
but the carry does not end there,
supppose you have two 4 bit numbers with all set to 1's if we add them up we can not represent them in 4 bits because that would only be one half of the addition! We can bypass this problem by adding in the carry bit, this extends the 4-bit output to 5 bits. And in 5 bits we CAN represent 32+32 (which is 1111 + 1111).