Need help with computer architecture problem. A MARIE-based computer has a memor
ID: 3868406 • Letter: N
Question
Need help with computer architecture problem.
A MARIE-based computer has a memory unit with 32 bits per word. The instruction set consists of 64 different operations. All instructions have an operation code part (opcode) and an address part (allowing for only one address). Each instruction is stored in one word of memory.
a) How many bits are needed for the opcode?
b) How many bits are left for the address part of theinstruction?
c) What is the maximum allowable size for memory if addressing mode is direct?
d) Given an instruction in hex of ABCDE333. In hex, what is the opcode and what is the address?
Explanation / Answer
Solution:
a)Answer:
2^6 = 64 which is equal 64, Therefore the operation code needs 6bits
b)Answer:
A: 32-6=26. There are 26 bits available for the address part of the instruction
c)Answer:
maximum allowable size for memory is 2^26=67108864