ALGORITHM 1: Implementation of bit masking and shifting by loading a 32-bit regi

Question

                    ALGORITHM 1: Implementation of bit masking and shifting by loading a 32-bit register with all 1's (this will be hexadecimal FFFFFFFF) then to perform an                     exclusive OR with a 32-bit hexadecimal value of AAAA5555 Then rotate the result 16 bits (either left or right) and finally display the result in hexadecimal.                 

                    ALGORITHM 2: evaluate the sum of the mathematical series (2x +4) where x goes from 1 through 5. With a loop in assembly language and Register Addressing Mode,                     Immediate Addressing Mode AND Direct Addressing Mode.
                

                    Finally TWO algorithms in just one assembly language prog.                 

Explanation / Answer

It is possible to use bitmasks to easily check the state of individual bits regardless of the other bits. Querying the status of the 4th bit

EG:

LOAD A, FFFFFFFF

AND FFFFFFFE => to make the LSB 0, since E=1110 in binary,

use, FFFFFFFB (B=1011 ) to mask the third bit to 0 from the last.

to make the bit 1, use 'OR 1111 (F)' at the appropriate locations

For shifting:

LOAD A, FFFFFFFF

RAL   

RAL

RAL

RAL => TO ROTATE OR SHIFT LEFT THE 16 BITS

LOAD A, FFFFFFFF

RAR

RAR

RAR

RAR => TO ROTATE OR SHIFT RIGHT THE 16 BITS

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