Question

You have designed an instruction set architecture (ISA), whose characteristics are;

• 16 diff operations (ADD, SUB, OUT, HLT etc.)

• 12-bit address (program counter (PC), a memory address register (MAR) etc.)

• 16-bit data registers (accumulators, B, Temp etc.)

• 16-bit instruction register (IR)

1) What will be the instruction size?

2) Opcode size?

3) Operand size?

4)A number of locations in memory?

5) Memory data size?

Answer 1

1) What will be the instruction size?

Opcode + address      4 + 12 = 16bits

2) Opcode size          4bits

3) Operand size         16bits

4)A number of locations in memory    2^12 = 4096

5) Memory data size                          4096 x 16