Question

Consider a hypothetical computer with an instruction set of only two n-but instructions. The first bit specifies the opcode, and the remaining bits specify one of the 2-1 n-bit words of main memory. The two instructions are as follows: SUBS X: Subtract the contents of location X from the accumulator, and store the result in location X and the accumulator JUMP X: Place address X in Program Counter A word in memory may contain either an instruction or a binary number in twos complement notation Demonstrate that this instruction repertoire is reasonably complete by specifying how the following operations can be performed: A. Data Transfer: Location X to accumulator, accumulator to location X B. Addition : Add contents of location X to accumulator. C. Conditional Branch. D. Logical OR. E. V/O Operations

Answer 1

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