Exercise 1.1 Converting between Numbering Systems Using the Windows Calculator 1. Click Start, click All Programs, click Accessories, and then click Calculator.
Step 1
This opens the Calculator application. 2. Click the View menu and then click Programmer. This switches the calculator to Programmer mode.
Step 2
3. Make sure that the Dec option is selected, indicating you are in Decimal mode. 4. Enter the number 77. You can either type 77 on your keyboard or click the number buttons on the Calculator application. 5. Click the Bin option to switch to Binary mode.
Step 4
Step 3
This changes the number to 1001101. 6. Click the Hex option to switch to Hexadecimal mode. This changes the number to 4D. 7. Close the Calculator application by clicking the Close button in the upper right corner of the Calculator window.
Understanding Input, Processing, and Output At their core, all computers are calculators. They accept numeric input (the data coming in), perform the requested math operation on it, and produce output (the data going out). A pocket calculator is a simple computer. You press the output Data going out of a computer buttons for the numbers you want, press a button (such as a plus or minus) for a mathematical operator, and then press the equals button to get the answer. Personal computers operate under the same basic principle. They accept input from the keyboard or mouse, process it, and send it out to the monitor or another output device. Of course, the data being moved through a PC is much more sophisticated than the data moving through a pocket calculator. Suppose, for example, that you press the letter k on the keyboard. Each character on the keyboard is represented by a numeric code. The keyboard sends that code to the PC. The PC’s operating system reviews the incoming code and determines what to do with it. Let us say that k is part of a sentence you input Data coming into a computer
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UNIT 1 Topic 1
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