Basic System Problem Analysis - August 2003

page 143/17/2003

Basic System Problem Analysis

Short vs. Long Pointers

Load and Store instructions that specify a space register of

zero intend that the hardware will derive the space register by

using the first 2 bits of the offset portion of the address and

add 4 to that giving the SR number to use.

LDW -296(0,30),22

If R30 contains 418432f0 the ‘4’ is 0100 in binary. The first 2

bits, are 01 + 4 = 5. So SR5 will be used to complete the

pointer.

Notes: