What are the relative advantages and disadvantages of general?purpose registers compared to separate address and data registers?

What will be an ideal response?


If you have different registers for different purposes, they can behave accordingly. For example, an address register or pointer register holds a single entity, the address. Consequently, you don’t have to worry about operations on bytes or other sub?words in an address register. All address register operations are wordlength because a pointer is a single entity. Moreover, addresses are considered as signed and all arithmetic is two’s complement. Similarly, only certain operations are permitted on an address (e.g., addition or subtraction). Logical operations like OR are not permitted on the contents of an address register. Finally, operations on an address register (apart from a compare) do not affect the condition codes. All this is true of the 68K family that implements separate address registers. By contrast, all operations are permitted on the contents of data registers, because data may represent any quantity.

A principal reason for providing separate address and data registers was to enforce good programming practice and to ensure that the programmer did not make certain types of error when handling addresses. Today, this notion has largely died and processors have dedicated address registers only if made necessary by their operation or for reasons of legacy (backward compatibility).

Computer Science & Information Technology

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Which of the following event descriptions best describes the mouse entered event?

a) The mouse button is pressed down b) The mouse button is pressed down and released without moving the mouse in between c) The mouse pointer is moved onto a component d) The mouse button is released e) The mouse is moved while the mouse button is pressed down

Computer Science & Information Technology

This approach starts at the physical layer of OSI and works its way up to the application layer.

What will be an ideal response?

Computer Science & Information Technology

Which file output option deletes the output produced by a cmdlet?

A. out-file B. delete-out C. out-null D. del-file

Computer Science & Information Technology

The method of creating a(n) ____________________ Web site depends on the amount of data being served out, the number of users potentially accessing that information simultaneously, the budget available, and the technology already being used.

Fill in the blank(s) with the appropriate word(s).

Computer Science & Information Technology