Addressing mode used by PC

Question

Comments

So, should I close it or Hide it ?

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you can leave it as is. May be someone can explain it.

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Okay.

Answer 1

" We have defined the Index mode by using general-purpose processor registers. Some computers have a version of this mode in which the program counter, PC, is used instead of a general-purpose register. Then, X(PC) can be used to address a memory location that is X bytes away from the location presently pointed to by the program counter. Since the addressed location is identified relative to the program counter, which always identifies the current execution point in a program, the name Relative mode is associated with this typeof addressing.
Relative mode—The effective address is determined by the Index mode using the program
counter in place of the general-purpose register Ri. "

-[Computeranization And Embedded Systems, Hamacher, Vranesic, Zaky, Manjikian, 6Ed, Mgh, 2012]

Comments

So, it  should be like , program counter is used in Relative Addressing mode.

Answer 2

In The case of relative addressing mode PC is used to hold next memory instruction for execution.

For Example ::

Suppose branch instruction I1 is 3Byte

BR:: 2000

I1      2004

I2      2008

I3       2012

2020

 PC will contain=2016

then Effective Address= PC + (move up or down)

Answer 3

Relative addressing mode is required where only offset is to be added with PC content.

Comments

what is mean by "offset" here?

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To calculate Effective address in order to fetch Instruction,
PC content + offset is sufficient.

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Sorry, I'm not getting how to apply addressing modes here.

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@Arjun sir,

i think offset here means size of current instruction..