Difference between revisions of "CSC103: DT's Notes 1"
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The image on the left, above, shows an ''integrated circuit'' (IC)close up. In reality the circuit is about as long as a quarter (and with newer technology even smaller). The image on the right shows what is inside the IC. Just 4 AND gates. There are other ICs that contain different types of gates, such as OR gates or Inverters. | The image on the left, above, shows an ''integrated circuit'' (IC)close up. In reality the circuit is about as long as a quarter (and with newer technology even smaller). The image on the right shows what is inside the IC. Just 4 AND gates. There are other ICs that contain different types of gates, such as OR gates or Inverters. | ||
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| + | ==Building a Two-Bit Adder with Logic Gates== | ||
| + | Shannon in 1948 wrote a Master's thesis at MIT that provided one of the major breakthroughs of the 20th century for computer science, and because computers are so important tools in science, for all of science. Shannon discovered that binary arirthmetic such as the binary addition could be performed using logic gates. | ||
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| + | The first step in figuring out how is to use a ''code'', and associate '''1''' with '''true''' and '''0''' with '''false'''. In this case the truth table for the '''AND''' operator can be expressed with 1s and 0s the same way it was with true and false: | ||
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| + | {| border="1" cellpadding="10" cellspacing="0" | ||
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| + | ! a '''and''' b | ||
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| + | ---- | ||
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Revision as of 21:15, 16 September 2013
--© D. Thiebaut 08:10, 30 January 2012 (EST)
