Question $(3)$ Consider a hypothetical $32-$bit microprocessor having $32-$bit instructions composed

of two fields: the first byte contains the opcode and the remainder the immediate operand or an

operand address.

a$.$ What is the maximum directly addressable memory capacity $($in bytes$)?$

b$.$ Discuss the impact on the system speed if the microprocessor bus has:

a$.32-$bit local address bus and a $16-$bit local data bus, or

b$.16-$bit local address bus and a $16-$bit local data bus.

c$.$ How many bits are needed for the program counter and the instruction register?

Answer

a$.224=16$ Mbytes

please explain how he got $224$ Mb