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Hi everyone -

I'm new to using Logic Circuit, and loving it so far. I've only run through some basics, like constructing basic logic chips from NANDs. At a single bit input level, everything is working fine.

I''ve now moved along to wanting to make some 16-bit variants and I've got myself in a tangle so hoping someone can explain some basics to me please.

I was just going to test things by having:
1. An input, set to 16 bits wide
2. A NAND, where I selected 16 from the drop-down next to the out-of-the-box gate
3. An output, again set to 16 bits

However, when I try to pull a truth table, I get a message saying the bit width of input and NAND don't match.

I'm wondering if what I'm trying to do is a bit of a nonsense approach, and whether I need to do something else (like make my own circuit with 16 inputs connected to 16 NANDs to 16 outputs... which doesn't sound quite right either.

All advice welcome, and thanks in advance!

The NAND gate have one bit output, no matter how many inputs it has. So if you connect one bit NAND output to 16 bit output pin you will get an error.
Can you explain what you want to build?

HI there -

Thanks for the assist!

I'm trying to work out how to represent the basic Not/And/Or logic, all capable of supporting 16-bit inputs and using only Nands.

I think I worked out what I needed to do from your answer. I put splitters on each side. Taking my 16-way Not, for example:

• I now have a 16-bit input going to a 16-way splitter.

• That feeds 16 NANDs in parallel, each of which has its 2 input pins joined together.

• The output of each NAND feeds to another splitter, reversed to allow it to feed a single pin.

• I then have a 16 bit-width output.

I'm still testing some values randomly from the truth table vs a calculator, but it's looking good.
e.g. 0000 1100 1011 0000 gives 1111 0011 0100 1111

Does that sound like the right approach to take?

Thanks again.

Probably it is. If you have any problems you can share your project here so it's easier to see what you have done.