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I did this 16 bit adder in a simulator. Something is wrong. The automatic check returned FAIL. What did I do wrong? How can I fix it?

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JRE
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Sonya Lyu
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    Please draw a neat version of this circuit. It is not clear which lines are connected or just in the background, which makes spotting the mistake nearly impossible. – Hans mitm Flammenwerfer Aug 15 '23 at 09:01
  • At the very least, if your buses are numbered starting from the bottom, arrange your adders in the same order! – Dave Tweed Aug 15 '23 at 12:00

1 Answers1

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You maximised lines crossing in the drawing.
This makes it difficult to spot missing connections, such as the carry from bit 1 to bit 2 (starting bit numbering at 0).

It may be easier to design a 4-bit full adder - and the 16-bit adder from 4-bit adders.

greybeard
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