Question

A computer uses a memory unit with 1M words of 32 bits each. A binary instruction code is stored in one word of memory. The instruction has five parts: 3 addressing modes, an operation code, a register code part to specify one of 8 registers, an input/ output (I/O) code to specify 8 operations and an address part (Marks 3 x 5 = 15)
• How many bits are there in the operation code, the register code part, I/O code part and the address part?
• Draw the instruction word format and indicate the number of bits in each part?
• How many bits are there in the data and address inputs of the memory

Answer 1

Explanation:

A computer uses a memory unit with 256K words of 32 bits each. A binary instruction code is stored in one word of memory. The instruction has four parts: an indirect bit, an operation code, a register code part to specify one of 64 registers, and an address part.

a) How many bits are there in the operation code, the register code part, and the address part?

b) Draw the instruction word format and indicate the number of bits in each part.

c) How many bits are there in the data and address inputs of the memory.

Memory

0 32 bits

1  

...  

256K 32