Address Register Indirect With Index (Base Displacement) Mode - Motorola MC68030 User Manual

2.4.8 Address Register Indirect with Index (Base Displacement) Mode
This addressing mode requires an index register indicator and an optional
16- or 32-bit sign-extended base displacement. The index register indicator
includes size and scaling information. The operand is in memory. The address
of the operand is the sum of the contents of the address register, the scaled
contents of the sign-extended index register, and .the base displacement.
In this mode, the address register, the index register, and the displacement
·are all optional. If none is specified, the effective address is zero. This mode
provides a data register indirect address when no address register is specified
and the index register is a data register (On).
GENERATION:
ASSEMBLER SYNTAX:
MODE:
REGISTER:
ADDRESS REGISTER:
BASE DISPLACEMENT:
INDEX REGISTER:
SCALE:
MEMORY ADDRESS:
31
31
EA
=
(An) + (Xn) + bd
(bd.An.XnSIZE ·SCALE)
110
n
An
SIGN EXTENDED VALUE
SIGN EXTENDED VALUE
31
SCALE VALUE
31
NUMBER OF EXTENSION WORDS: 1. 2. OR 3
MOTOROLA
MC68030 USER'S MANUAL 2-13