A central processing unit (CPU) typically provides various addressing modes that identify the operand(s) of each instruction. Which of the following addressing modes specifies the operand in the instruction itself? (Wentz QOTD)
A. Register addressing
B. Direct addressing
C. Indirect addressing
D. Immediate addressing
Kindly be reminded that the suggested answer is for your reference only. It doesn’t matter whether you have the right or wrong answer. What really matters is your reasoning process and justifications.
My suggested answer is D. Immediate addressing.
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It’s common for a CPU instruction to load values into registers for computing. A CPU’s addressing mode means how the CPU locates the value of interest. Values can be given immediately in instructions (immediate addressing), read from registers (register addressing), or loaded from the main memory (direct, indirect, base+offset).
An instruction may direct the CPU to load a value into the register by:
- providing a memory address where the value resides (direct addressing),
- providing a memory address that points to another memory address where the value resides (indirect addressing), or
- providing a memory address as the base (the start point) and the offset (the distance) to where the value resides (base+offset addressing).
中央處理單元 (CPU) 通常提供各種尋址模式(addressing mode)來標識每條指令的運算元(operand)。 以下哪一項尋址模式在指令本身指定了的運算元？ (Wentz QOTD)