
MOTOROLA
MC68330 USER'S MANUAL
5- 5
Program Counter Indirect with Index
Absolute
Immediate
Included in the register indirect addressing modes are the capabilities to postincrement,
predecrement, and offset. The PC relative mode also has index and offset capabilities. In
addition to these addressing modes, many instructions implicitly specify the use of the SR,
SP and/or PC. Addressing is explained fully in 5.3 Data Organization and Addressing
Capabilities.
5.1.7 Instruction Set
The instruction set of the CPU32 is very similar to that of the MC68020 (see Table 5-1).
Two new instructions have been added to facilitate embedded control applications:
LPSTOP and table lookup and interpolate (TBL). The following M68020 instructions are
not implemented on the CPU32:
BFxxx — Bit Field Instructions (BFCHG, BFCLR, BFEXTS, BFEXTU, BFFFO, BFINS,
BFSET, BFTST)
CALLM, RTM — Call Module, Return Module
CAS, CAS2 — Compare and Set (Read-Modify-Write Instructions)
cpxxx — Coprocessor Instructions (cpBcc, cpDBcc, cpGEN, cpRESTORE, cpSAVE,
cpScc, cpTRAPcc)
PACK, UNPK — Pack, Unpack BCD Instructions
The CPU32 traps on unimplemented instructions or illegal effective addressing modes,
allowing user-supplied code to emulate unimplemented capabilities or to define special-
purpose functions. However, Motorola reserves the right to use all currently
unimplemented instruction operation codes for future M68000 core enhancements.
5.1.7.1 TABLE LOOKUP AND INTERPOLATE INSTRUCTIONS. To maximize
throughput for real-time applications, reference data is often "particulated'' and stored in
memory for quick access. The storage of each data point would require an inordinate
amount of memory. The table instruction requires only a sample of data points stored in
the array, thus reducing memory requirements. Intermediate values are recovered with
this instruction via linear interpolation. The results may be rounded by a round-to-nearest
algorithm.
Table 5-1. Instruction Set Summary
Mnemonic
Description
Mnemonic
Description
ABCD
Add Decimal with Extend
MOVEA
Move Address
ADD
Add
MOVE CCR
Move Condition Code Register
ADDA
Add Address
MOVE SR
Move to/from Status Register
ADDI
Add Immediate
MOVE USP
Move User Stack Pointer
ADDQ
Add Quick
MOVEC
Move Control Register
AND
Logical AND
MOVEM
Move Multiple Registers
ANDI
Logical AND Immediate
MOVEP
Move Peripheral Data
ASL
Arithmetic Shift Left
MOVEQ
Move Quick
ASR
Arithmetic Shift Right
MOVES
Move Alternate Address Space
Bcc
Branch Conditionally (16 Tests)
MULS
Signed Multiply
BCHG
Bit Test and Change
MULU
Unsigned Multiply