The Core
MOTOROLA
MC68322 USER’S MANUAL
3-3
3.2 DATA TYPES AND ADDRESSING MODES
The core supports the basic data formats of the M68000 Family. The instruction set supports
operations on other data formats, such as memory addresses. The operand data formats
supported by the core are the standard twos-complement data formats defined in the
M68000 Family architecture. Registers, memory, or instructions themselves can contain
integer unit operands. The operand size for each instruction is either explicitly encoded in
the instruction or implicitly defined by the instruction operation. Table 3-1 lists the data
formats for the core. Refer to the
M68000 Family Programmer’s Reference Manual for
details on data format organization in registers and memory.
The core also supports the basic addressing modes of the M68000 Family. The register
indirect addressing modes support postincrement, predecrement, offset, and index
capabilities. The program counter relative mode also supports indexing and offsetting.
Table 3-2 lists a summary of the data addressing modes for the core. Refer to the
M68000
Family Programmer’s Reference Manual for details on the core’s effective addressing
modes.
Table 3-1. Processor Data Formats
OPERAND DATA FORMAT
SIZE
Bit
1 Bit
Binary-Coded Decimal (BCD)
8 Bits
Byte Integer
8 Bits
Word Integer
16 Bits
Long-Word Integer
32 Bits
Table 3-2. Effective Addressing Modes
ADDRESSING MODES
SYNTAX
Register Direct Addressing
Data Register Direct
Address Register Direct
EA = Dn
EA = An
Absolute Data Addressing
Absolute Short
Absolute Long
EA = (Next Word)
EA = (Next Two Words)
Program Counter Relative Addressing
Relative With Offset
Relative With Index and Offset
EA = (PC) + d16
EA = (PC) + d8
Register Indirect Addressing
Register Indirect
Postincrement Register Indirect
Predecrement Register Indirect
Register Indirect With Offset
Indexed Register Indirect With Offset
EA = (An)
EA = (An), An
=An + N
An
= An –N, EA = (An)
EA = (An) + d16
EA = (An) + (Xn) + d8
Immediate Data Addressing
Immediate
Quick Immediate
DATA = Next Word(s)
Inherent Data
Implied Addressing
Implied Register
EA = SR, USP, SSP, PC
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Freescale Semiconductor, Inc.
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