Motorola CPU32 Manuel d'utilisateur Page 51

  • Télécharger
  • Ajouter à mon manuel
  • Imprimer
  • Page
    / 646
  • Table des matières
  • MARQUE LIVRES
  • Noté. / 5. Basé sur avis des utilisateurs
Vue de la page 50
Addressing Capabilities
2-10
M68000 FAMILY PROGRAMMER’S REFERENCE MANUAL
MOTOROLA
2.2.8 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 operand’s address is the sum of the contents of
the address register, the base displacement, and the scaled contents of the sign-extended
index register.
In this mode, the address register, the index register, and the displacement are all optional.
The effective address is zero if there is no specification. This mode provides a data register
indirect address when there is no specific address register and the index register is a data
register.
.
+
+
X
CONTENTS
SIGN-EXTENDED VALUE
SCALE VALUE
CONTENTS
31 0
31
0
31 0
031
SIGN-EXTENDED VALUE
BASE DISPLACEMENT
INDEX REGISTER
SCALE
OPERAND POINTER
EA = (An) + (Xn) + bd
(bd,An,Xn.SIZE*SCALE)
110
REG. NO.
1,2, OR 3
GENERATION:
ASSEMBLER SYNTAX:
EA MODE FIELD:
EA REGISTER FIELD:
NUMBER OF EXTENSION WORDS:
ADDRESS REGISTER
MEMORY
OPERAND
POINTS TO
Vue de la page 50
1 2 ... 46 47 48 49 50 51 52 53 54 55 56 ... 645 646

Commentaires sur ces manuels

Pas de commentaire