INTRODUCTION TO MICROPEOCESSOR
MODEL OF MICROPROCESSOR
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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To identify that which key is being pressed, we need to:
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ground all the pins of the port at a time
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ground pins of the port one at a time
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connect all the pins of the port to the main supply at a time
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none of the mentioned
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Explanation:
Detailed explanation-1: -3. To detect that in which column, the key is placed? Explanation: We can mask or we can even rotate the bits to check that particularly in which column is the key placed.
Detailed explanation-2: -An easy way to detect if any key in the matrix is pressed is to output 0’s to all rows and then check the column to see if a pressed key has connected a low to a column. In the algorithm we first output lows to all the rows and check the columns over and over until the column are all high.
There is 1 question to complete.