Q 14.. PLEASE ANSWER.

Question

Answer 1

If we see, 11 bits(0-10) are used to address in the instruction. So, main memory can be up to 2¹¹ bytes. 

This assumes byte addressing and that there is no virtual memory. 

If word addressing is used, we get 2¹¹ words = 2 * 2¹¹ = 2¹² bytes as each word here is 16 bits = 2 bytes.

http://www.cs.ucla.edu/classes/winter04/csM151B/l2/examples/ByteVSWordAddr.pdf

Comments

Could you tell me why we haven't considered address mode bits in calulation of main memory address range?

for ex: if register indirect mode is used, then range of mem addresses will be more than 2¹²  bytes.

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Yes. Thats possible. But then absolute addressing won't be possible. If we use only register indirect addressing, we could address up to 2¹⁶ bytes of memory. 

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ok.. thank you

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you are welcome :)

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sir , plzzzz tellme why u hav multiplied 2*2¹¹ plzzzz clearify this plzz i cant understand

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That is only if we use word addressing- that is CPU can fetch only 16 bits and not lower. In such a CPU, suppose we write a C code and a char is of 8 bits. Still, CPU will be fetching 16 bits and so the generated code should handle this problem.