The easiest way to make a NAND gate is to NOT and AND gate. However, on the BLOG there is only one and gate so I had asked how to make another NAND gate from the remaining modules. Yannis shows how to make a NAND from 2 NOTS and and OR. However, Since one of the NOT modules is used in the creation of the first NAND gate, another one needs to found to make a second NAND gate.
As far as the charts go, think of the 1’s as a voltage present and 0’s as no voltage. So, from the chart a NAND gates outputs voltage in all cases except when there is voltage on both inputs. So, while the same results are gained from OR’ing two NOT gates, the same result is achieved by NOT’ing an AND.
A B A+B NOT(A+B)
1 1 1 0
1 0 0 1
0 1 0 1
0 0 0 1
The bigger question in your mind is probably, “Why do I want a couple of NAND gates anyhow?” The reason is that you can construct a flip-flop from 2 NAND gates. By feeding the outputs of the NAND gates into the input of each other, a basic memory module is created. In particular I would like to make a toggle flip-flop. This is a flip flop that when pulsed outputs a constant voltage (high or low, 1 or 0) until it is pulsed again. If the steady state is high then pulsing it makes it low. The usefulness is that it *stays* high or low until pulsed again. If I can’t figure out how to wire one of these up, I’ll have to get out the soldering iron and make a bunch of these as I’m constantly wanting one for complex sequencer work!
Clear as mud?
James R. Coplin
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If anyone asks of my whereabouts,
simply tell them i've gone out the window
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From: darkstr1746@...
[mailto:darkstr1746@...]
Sent: Friday, October 01, 2004
9:11 AM
To: SergeModular@yahoogroups.com
Subject: Re: [SergeModular] Digest
Number 721/NAND gates
I'm sorry, but i'm a dumb ass. Is there another way to explain this. I just don't get it.
kind regards
john duval
-------------- Original message --------------
Hi James,
to construct a NAND gate you have to OR two NOT gates:
The truth table for NAND is
A B A NAND B
0 0 1
0 1 1
1 0 1
1 1 0
Now:
A B NOT A NOT B (NOT A) OR (NOT B)
0 0 1 1 1
0 1 1 0 1
1 0 0 1 1
1 1 0 0 0
The cool thing about the BLOG module is that there are two NOTs so you can actually construct the above gate easily.
I hope this helps!
Yannis
From: "James R. Coplin"
Subject: RE: Re: Sequencer length double.... Chris ?
Anyone successfully wired up a flip-flop with a pair of blogs? I only have
the ons blog so I can't try it. Alternately, can a nand gate be constructed
with an or, xor, not and some other modules?
James R. CoplinDo you Yahoo!?
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Keep on Patchin'!
Keep on Patchin'!