MC68EC000EI16 Freescale Semiconductor, MC68EC000EI16 Datasheet - Page 58

• Manufacturer Part Number: MC68EC000EI16
• Description: IC MPU 32BIT 16MHZ 68-PLCC
• Manufacturer: Freescale Semiconductor

Specifications of MC68EC000EI16

• Processor Type: M680x0 32-Bit
• Speed: 16MHz
• Voltage: 3.3V, 5V
• Mounting Type: Surface Mount
• Package / Case: 68-PLCC
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Features: -

2.2.15 Program Counter Memory Indirect Preindexed Mode
This mode is similar to the mode described in 2.2.10 Memory Indirect Preindexed Mode ,
but the PC is the base register. Both the operand and operand address are in memory. The
processor calculates an intermediate indirect memory address by adding the PC contents,
a base displacement, and the scaled contents of an index register. The processor accesses
a long word at immediate indirect memory address and adds the optional outer
displacement to yield the effective address. The value of the PC is the address of the first
extension word. This is a program reference allowed only for reads.
In the syntax for this mode, brackets enclose the values used to calculate the intermediate
memory address. All four user-specified values are optional. The user must supply the
assembler notation ZPC showing that the PC is not used. This allows the user to access the
program space without using the PC in calculating the effective address. Both the base and
outer displacements may be null, word, or long word. When omitting a displacement or
suppressing an element, its value is zero in the effective address calculation.
MOTOROLA
GENERATION:
ASSEMBLER SYNTAX:
EA MODE FIELD:
EA REGISTER FIELD:
NUMBER OF EXTENSION WORDS:
PROGRAM COUNTER
BASE DISPLACEMENT
INDEX REGISTER
SCALE
OPERAND POINTER
MEMORY
OUTER DISPLACEMENT
MEMORY
INTERMEDIATE
ADDRESS
M68000 FAMILY PROGRAMMER’S REFERENCE MANUAL
31
31
31
EA = (bd + PC) + Xn.SIZE*SCALE + od
([bd,PC,Xn.SIZE*SCALE],od)
111
011
1,2,3,4, or 5
SIGN-EXTENDED VALUE
SIGN-EXTENDED VALUE
SIGN-EXTENDED VALUE
.
31
31
31
31
SCALE VALUE
VALUE AT INDIRECT MEM. ADDRESS IN PROG. SPACE
INDIRECT MEMORY ADDRESS
0
0
0
CONTENTS
CONTENTS
POINTS TO
OPERAND
POINTS TO
X
Addressing Capabilities
+
+
+
0
0
0
0
2-17