Difference between revisions of "CSC103: DT's Notes 1"
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| − | We are very close to understanding how the processor runs programs. We have seen that computers work with electricity, and that information is coded as 0s and 1s. We refer to an information cell that contains a 0 or a 1 as a ''bit''. The memory is a collection of boxes that contain bits. We refer to these boxes as ''words'' | + | We are very close to understanding how the processor runs programs. We have seen that computers work with electricity, and that information is coded as 0s and 1s. We refer to an information cell that contains a 0 or a 1 as a ''bit''. The memory is a collection of boxes that contain bits. We refer to these boxes as ''words'', or ''Memory words''. |
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| + | Before we continue, let's look at a big of magic! The magic requires building a simple circuit with AND and NOT gates, as shown below: | ||
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| + | <center>[[Image:CSC103FlipFlop1.jpg|600px]]</center> | ||
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| + | You may want to spend the time building it up with our [http://tinyurl.com/103applets| circuit simulator]. | ||
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| + | When you have your circuit built, why don't you turn the power on and activate the two inputs (on the left) randomly, and when you are done, bring the two inputs back to 1 1, i.e. both red. Observe the output. Is it red? black? Anyhow, activate the inputs again, randomly, bringing them back to 1 1 (red red) at the end of your experiment. Chances are the output will be different from the last time you stopped. This is pretty amazing, if you think about it. We are using logic circuit, gates that implement the truth table of mathematically immutable laws, the laws of logic, but this circuit that we have built does not always output the same information, even when the two inputs are identical. | ||
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The memory is a collection of billions of memory words, each one storing a collection of bits. We saw earlier that a collection of bits can actually represents a binary number, and each binary number has an equivalent decimal number. So we can actually say that the memory is a collection of cells that contain numbers. It's easier for us human to deal with decimal numbers, so that's what we are going to do in the remainder of this section, but actually all the numbers in questions are binary. Makes sense? | The memory is a collection of billions of memory words, each one storing a collection of bits. We saw earlier that a collection of bits can actually represents a binary number, and each binary number has an equivalent decimal number. So we can actually say that the memory is a collection of cells that contain numbers. It's easier for us human to deal with decimal numbers, so that's what we are going to do in the remainder of this section, but actually all the numbers in questions are binary. Makes sense? | ||
Revision as of 08:45, 22 September 2013
--© D. Thiebaut 08:10, 30 January 2012 (EST)
