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MOTOROLA
MC68306 USER'S MANUAL
4- 7
Table 4-3. Notation Conventions (Concluded)
Register Codes
*
General Case.
C
Carry Bit in CCR
cc
Condition Codes from CCR
FC
Function Code
N
Negative Bit in CCR
U
Undefined, Reserved for Motorola Use.
V
Overflow Bit in CCR
X
Extend Bit in CCR
Z
Zero Bit in CCR
—
Not Affected or Applicable.
Stack Pointers
SP
Active Stack Pointer
SSP
Supervisor Stack Pointer
USP
User Stack Pointer
Miscellaneous
<ea>
Effective Address
<label>
Assemble Program Label
<list>
List of registers, for example D3–D0.
LB
Lower Bound
m
Bit m of an Operand
m–n
Bits m through n of Operand
UB
Upper Bound
4.4 EC000 CORE INSTRUCTION SET OVERVIEW
Design of the instruction set gives special emphasis to support of structured, high-level
languages and to ease of assembly language programming. Each instruction, with a few
exceptions, operates on bytes, words, and long words, and most instructions can use any
of the 14 addressing modes. Over 1000 useful instructions are provided by combining
instruction types, data types, and addressing modes. These instructions include signed
and unsigned multiply and divide, "quick" arithmetic operations, BCD arithmetic, and
expanded operations (through traps). Additionally, the highly symmetric, proprietary
microcoded structure of the instruction set provides a sound, flexible base for the future.
The EC000 core instruction set is listed in Table 4-4. For detailed information on the
EC000 core instruction set, refer to M68000PM/AD,
M68000 Programmer's Reference
Manual.