# And16 help

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## And16 help

 I am working my way through the book and also trying to understand how the electronic circuits would look as I am going through each gate but I am really struggling to understand the concept of the AND16 gate. I am trying to understand how the gate would look on paper first. Is it simply 16 AND gates, which means 32 inputs(16*a and 16*b) and 16 outputs. How would the inputs be connected to the bus if it is only 16bits wide and there are 32 inputs. Not sure if I am looking at it all wrong. Any help would be much appreciated. thanks        Gareth p.s. This is just a hobby interest for me.
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## Re: And16 help

 Look again. How wide is the A input bus? And how wide is the B input bus?
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## Re: And16 help

 Ok so effectively you have two 16bit inputs. Which leads to the bit that I am finding really confusing, If the bits being sent to the gate are only 16 bits then that means there are sixteen inputs that aren`t receiving anything. Is it a case of a 16bit bus has 32 wire and the other sixteen bits are padded with 0`s or am I looking at this completely wrong. Thanks for the help.               Gareth
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## Re: And16 help

 Gazza wrote Ok so effectively you have two 16bit inputs. It's no more complicated than that. Imagine sixteen wires labeled a0 - a15, and sixteen wires labeled b0 - b15. How would you connect those 32 wires to sixteen one-bit And gates?
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## Re: And16 help

 Ok sorry for being stupid about something that should be so simple but if a 16bit input (i.e. 1010101010101010) is sent down a bus that has 32 wires which inputs of the 32 that the AND gate has receive these signals and what happens to the other inputs. Again sorry for being a bit stupid and thanks for the help so far.                 Gareth
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## Re: And16 help

 Administrator The 16-bit a bus is completely independent of the 16-bit b bus. Have you made and tested your Not16?  If you have, model the And16 after your Not16. You will have 16 Ands in the PARTS section. Each And will have its a inputs connected to a bit of the a bus, and its b input connected to the corresponding bit of the b bus. If you have not made your Not16 yet, you may be confused about what the And16 gate is. It is not a 16 input And gate with one output, rather it is 16 independent 2 input And gates, one for each bit of the a, b and out buses. --Mark