1.1 Integer Unit User Programming Model 1-2
1.1.1 Data Registers (D7 – D0)? . . 1-2
1.1.2 Address Registers (A7 – A0)? 1-2
1.1.3 Program Counter?? 1-3
1.1.4 Condition Code Register?? 1-3
1.2 Floating-Point Unit User Programming Model . 1-4
1.2.1 Floating-Point Data Registers (FP7 – FP0) . . 1-4
1.2.2 Floating-Point Control Register (FPCR) 1-5
1.2.2.1 Exception Enable Byte? 1-5
1.2.2.2 Mode Control Byte?? 1-5
1.2.3 Floating-Point Status Register (FPSR) . 1-5
1.2.3.1 Floating-Point Condition Code Byte. . 1-5
1.2.3.2 Quotient Byte1-6
1.2.3.3 Exception Status Byte . 1-6
1.2.3.4 Accrued Exception Byte . . 1-7
1.2.4 Floating-Point Instruction Address Register (FPIAR)?? . 1-8
1.3 Supervisor Programming Model? . . 1-8
1.3.1 Address Register 7 (A7)? . . 1-10
1.3.2 Status Register?? 1-10
1.3.3 Vector Base Register (VBR)?? . . 1-11
1.3.4 Alternate Function Code Registers (SFC and DFC)?? . 1-11
1.3.5 Acu Status Register (MC68EC030 only)? 1-11
1.3.6 Transparent Translation/access Control Registers?? . . 1-12
1.3.6.1 Transparent Translation/access Control Register Fields for the
M680301-12
1.3.6.2 Transparent Translation/access Control Register Fields for the
M680401-13
1.4 Integer Data Formats??? 1-14
1.5 Floating-Point Data Formats? 1-15
1.5.1 Packed Decimal Real Format?? . 1-15
1.5.2 Binary Floating-Point Formats?? . 1-16
1.6 Floating-Point Data Types? . . 1-17
1.6.1 Normalized Numbers? . . 1-18
1.6.2 Denormalized Numbers? 1-18
1.6.3 Zeros? 1-19
1.6.4 Infinities . 1-19
1.6.5 Not-A-Numbers?? 1-19
1.6.6 Data Format and Type Summary? . 1-20
1.7 Organization of Data in Registers? . . 1-25
1.7.1 Organization of Integer Data Formats in Registers?? . . 1-25
1.7.2 Organization of Integer Data Formats in Memory??? 1-27
1.7.3 Organization of Fpu Data Formats in Registers and Memory?? 1-30
Section 2
Addressing Capabilities
2.1 Instruction Format?? 2-1
2.2 Effective Addressing Modes . . 2-4
2.2.1 Data Register Direct Mode? . 2-5
2.2.2 Address Register Direct Mode? . . 2-5
2.2.3 Address Register Indirect Mode?? 2-5
2.2.4 Address Register Indirect with Postincrement Mode? . . 2-6
2.2.5 Address Register Indirect with Predecrement Mode?? . . 2-7
2.2.6 Address Register Indirect with Displacement Mode?? . . 2-8
2.2.7 Address Register Indirect with Index (8-Bit Displacement) Mode? . 2-9
2.2.8 Address Register Indirect with Index (Base Displacement) Mode 2-10
2.2.9 Memory Indirect Postindexed Mode . . 2-11
2.2.10 Memory Indirect Preindexed Mode? 2-12
2.2.11 Program Counter Indirect with Displacement Mode?? . 2-13
2.2.12 Program Counter Indirect with Index (8-Bit Displacement) Mode? 2-14
2.2.13 Program Counter Indirect with Index (Base Displacement) Mode 2-15
2.2.14 Program Counter Memory Indirect Postindexed Mode? . . 2-16
2.2.15 Program Counter Memory Indirect Preindexed Mode?? 2-17
2.2.16 Absolute Short Addressing Mode? . 2-18
2.2.17 Absolute Long Addressing Mode . . 2-18
2.2.18 Immediate Data?? 2-19
2.3 Effective Addressing Mode Summary . . 2-19
2.4 Brief Extension Word Format Compatibility . . 2-21
2.5 Full Extension Addressing Modes? . . 2-22
2.5.1 No Memory Indirect Action Mode? . 2-24
2.5.2 Memory Indirect Modes?? 2-25
2.5.2.1 Memory Indirect with Preindex . . 2-25
2.5.2.2 Memory Indirect with Postindex . 2-26
2.5.2.3 Memory Indirect with Index Suppressed.. 2-27
2.6 Other Data Structures?? . . 2-28
2.6.1 System Stack. 2-28
2.6.2 Queues . 2-29
Section 3
Instruction Set Summary
3.1 Instruction Summary??? . 3-1
3.1.1 Data Movement Instructions? 3-5
3.1.2 Integer Arithmetic Instructions?? . . 3-6
3.1.3 Logical Instructions??? . 3-8
3.1.4 Shift and Rotate Instructions? 3-8
3.1.5 Bit Manipulation Instructions?? . . 3-10
3.1.6 Bit Field Instructions?? . . 3-10
3.1.7 Binary-Coded Decimal Instructions? 3-11
3.1.8 Program Control Instructions? . . 3-11
3.1.9 System Control Instructions 3-12
3.1.10 Cache Control Instructions (MC68040) 3-14
3.1.11 Multiprocessor Instructions? 3-14
3.1.12 Memory Management Unit (MMU) Instructions?? . . 3-15
3.1.13 Floating-Point Arithmetic Instructions . 3-15
3.2 Integer Unit Condition Code Computation? 3-17
3.3 Instruction Examples??? 3-20
3.3.1 Using the Cas and Cas2 Instructions . 3-20
3.3.2 Using the Moves Instruction?? . . 3-20
3.3.3 Nested Subroutine Calls? . . 3-20
3.3.4 Bit Field Instructions?? . . 3-20
3.3.5 Pipeline Synchronization with the Nop Instruction?? 3-21
3.4 Floating-Point Instruction Details?? 3-21
3.5 Floating-Point Computational Accuracy . 3-23
3.5.1 Intermediate Result??? 3-24
3.5.2 Rounding the Result?? . . 3-25
3.6 Floating-Point Postprocessing?? . . 3-27
3.6.1 Underflow, Round, Overflow?? . . 3-28
3.6.2 Conditional Testing??? 3-28
3.7 Instruction Descriptions?? . 3-32
8.1.1 Coprocessor ID Field?? 8-1
8.1.2 Effective Address Field?? . 8-1
8.1.3 Register/Memory Field?? . 8-1
8.1.4 Source Specifier Field?? . . 8-1
8.1.5 Destination Register Field? . . 8-2
8.1.6 Conditional Predicate Field? . 8-2
8.1.7 Shift and Rotate Instructions? 8-2
8.1.7.1 Count Register Field? . . 8-2
8.1.7.2 Register Field8-2
8.1.8 Size Field. 8-4
8.1.9 Opmode Field . 8-4
8.1.10 Address/Data Field??? . 8-4
8.2 Operation Code Map??? . 8-4
Appendix A
Processor Instruction Summary
A.1 MC68000, MC68008, MC68010 Processors . A-12
A.1.1 M68000, MC68008, and MC68010 Instruction Set?? . . A-12
A.1.2 MC68000, MC68008, and MC68010 Addressing Modes? A-16
A.2 MC68020 Processors?? A-17
A.2.1 MC68020 Instruction Set? . . A-17
A.2.2 MC68020 Addressing Modes?? . A-20
A.3 MC68030 Processors?? A-21
A.3.1 MC68030 Instruction Set? . . A-21
A.3.2 MC68030 Addressing Modes?? . A-24
A.4 MC68040 Processors?? A-25
A.4.1 MC68040 Instruction Set? . . A-25
A.4.2 MC68040 Addressing Modes?? . A-29
A.5 MC68881/MC68882 Coprocessors? . A-30
A.5.1 MC68881/MC68882 Instruction Set . . A-30
A.5.2 MC68881/MC68882 Addressing Modes? A-31
A.6 MC68851 Coprocessors? . A-31
A.6.1 MC68851 Instruction Set? . . A-31
A.6.2 MC68851 Addressing Modes?? . A-31
C.1 S-Record ContentC-1
C.2 S-Record Types . C-2
C.3 S-Record Creation?? C-3
1-1 M68000 Family User Programming Model 1-2
1-2 M68000 Family Floating-Point Unit User Programming Model....... 1-4
1-3 Floating-Point Control Register ....... 1-5
1-4 FPSR Condition Code Byte 1-6
1-5 FPSR Quotient Code Byte . 1-6
1-6 FPSR Exception Status Byte .......... 1-6
1-7 FPSR Accrued Exception Byte ....... 1-7
1-8 Status Register 1-11
1-9 MC68030 Transparent Translation/MC68EC030 Access
Control Register Format... 1-12
1-10 MC68040 and MC68LC040 Transparent Translation/MC68EC040
Access Control Register Format ... 1-13
1-11 Packed Decimal Real Format ....... 1-16
1-12 Binary Floating-Point Data Formats ........ 1-16
1-13 Normalized Number Format.......... 1-18
1-14 Denormalized Number Format...... 1-18
1-15 Zero Format .... 1-19
1-16 Infinity Format . 1-19
1-17 Not-A-Number Format...... 1-19
1-19 Organization of Integer Data Formats in Address Registers......... 1-26
1-18 Organization of Integer Data Formats in Data Registers .............. 1-26
1-20 Memory Operand Addressing ....... 1-27
1-21 Memory Organization for Integer Operands 1-29
1-22 Organization of FPU Data Formats in Memory............ 1-30
2-1 Instruction Word General Format.... 2-1
2-2 Instruction Word Specification Formats .... 2-2
2-3 M68000 Family Brief Extension Word Formats............ 2-21
2-4 Addressing Array Items.... 2-23
2-5 No Memory Indirect Action............ 2-24
2-6 Memory Indirect with Preindex...... 2-26
2-7 Memory Indirect with Postindex ... 2-27
2-8 Memory Indirect with Index Suppress.... 2-27
3-1 Intermediate Result Format........... 3-24
3-2 Rounding Algorithm Flowchart...... 3-26
3-3 Instruction Description Format ...... 3-33
B-1 MC68000 Group 1 and 2 Exception Stack Frame .........B-3
B-2 MC68000 Bus or Address Error Exception Stack Frame................B-3
B-3 Four-Word Stack Frame, Format $0 .........B-3
B-4 Throwaway Four-Word Stack Frame, Format $1...........B-3
B-5 Six-Word Stack Frame, Format $2..B-4
B-6 MC68040 Floating-Point Post-Instruction Stack Frame, Format $3B-4
B-7 MC68EC040 and MC68LC040 Floating-Point Unimplemented
Stack Frame, Format $4 ....B-5
B-8 MC68040 Access Error Stack Frame, Format $7 .........B-5
B-9 MC68010 Bus and Address Error Stack Frame, Format $8 ..........B-6
B-10 MC68020 Bus and MC68030 Coprocessor Mid-Instruction
Stack Frame, Format $9 ....B-6
B-11 MC68020 and MC68030 Short Bus Cycle Stack Frame, Format $A...............B-7
B-12 MC68020 and MC68030 Long Bus Cycle Stack Frame, Format $B...............B-8
B-13 CPU32 Bus Error for Prefetches and Operands Stack Frame, Format $C.....B-8
B-14 CPU32 Bus Error on MOVEM Operand Stack Frame, Format $C B-9
B-15 CPU32 Four- and Six-Word Bus Error Stack Frame, Format $C...B-9
B-16 MC68881/MC68882 and MC68040 Null Stack FrameB-10
B-17 MC68881 Idle Stack Frame .........B-10
B-18 MC68881 Busy Stack Frame .......B-11
B-19 MC68882 Idle Stack Frame ..........B-11
B-20 MC68882 Busy Stack Frame ........B-11
B-21 MC68040 Idle Busy Stack Frame .B-12
B-22 MC68040 Unimplimented Instruction Stack Frame......B-12
B-23 MC68040 Busy Stack Frame ........B-13
C-1 Five Fields of an S-Record.C-1
C-2 Transmission of an S1 Record........C-4
1-1 Supervisor Registers Not Related To Paged Memory Management .............. 1-9
1-2 Supervisor Registers Related To Paged Memory Management.. 1-10
1-3 Integer Data Formats ...... 1-15
1-4 Single-Precision Real Format Summary Data Format 1-21
1-5 Double-Precision Real Format Summary... 1-22
1-6 Extended-Precision Real Format Summary................ 1-23
1-6 Extended-Precision Real Format Summary (Continued)............. 1-24
1-7 Packed Decimal Real Format Summary 1-24
1-8 MC68040 FPU Data Formats and Data Types ........... 1-30
2-1 Instruction Word Format Field Definitions? 2-3
2-2 IS-I/IS Memory Indirect Action Encodings 2-4
2-3 Immediate Operand Location....... 2-19
2-4 Effective Addressing Modes and Categories .............. 2-20
3-1 Notational Conventions ..... 3-2
3-1 Notational Conventions (Continued) ........ 3-3
3-1 Notational Conventions (Concluded) ....... 3-4
3-2 Data Movement Operation Format. 3-6
3-3 Integer Arithmetic Operation Format........ 3-7
3-4 Logical Operation Format.. 3-8
3-5 Shift and Rotate Operation Format? 3-9
3-6 Bit Manipulation Operation Format ........ 3-10
3-7 Bit Field Operation Format ........... 3-10
3-8 Binary-Coded Decimal Operation Format.. 3-11
3-9 Program Control Operation Format........ 3-12
3-10 System Control Operation Format ......... 3-13
3-11 Cache Control Operation Format. 3-14
3-12 Multiprocessor Operations ........... 3-14
3-13 MMU Operation Format .. 3-15
3-14 Dyadic Floating-Point Operation Format 3-16
3-15 Dyadic Floating-Point Operations? 3-16
3-16 Monadic Floating-Point Operation Format . 3-16
3-17 Monadic Floating-Point Operations........ 3-17
3-18 Integer Unit Condition Code Computations 3-18
3-19 Conditional Tests ............ 3-19
3-20 Operation Table Example (FADD Instruction)............. 3-22
3-21 FPCR Encodings............. 3-25
3-22 FPCC Encodings............. 3-29
3-23 Floating-Point Conditional Tests .. 3-31
5-1 Directly Supported Floating-Point Instructions .............. 5-2
5-2 Indirectly Supported Floating-Point Instructions............ 5-3
7-1 MC68020 Instructions Not Supported...... 7-1
7-2 M68000 Family Addressing Modes 7-2
7-3 CPU32 Instruction Set....... 7-3
8-1 Conditional Predicate Field Encoding ...... 8-3
8-2 Operation Code Map......... 8-4
A-1 M68000 Family Instruction Set And Processor Cross-Reference..A-1
A-2 M68000 Family Instruction Set.......A-8
A-3 MC68000 and MC68008 Instruction SetA-12
A-4 MC68010 Instruction Set.A-14
A-5 MC68000, MC68008, and MC68010 Data Addressing Modes....A-16
A-6 MC68020 Instruction Set Summary .......A-17
A-7 MC68020 Data Addressing Modes ........A-20
A-8 MC68030 Instruction Set Summary .......A-21
A-9 MC68030 Data Addressing Modes ........A-24
A-10 MC68040 Instruction Set.A-25
A-11 MC68040 Data Addressing Modes ........A-29
A-12 MC68881/MC68882 Instruction Set.......A-30
A-13 MC68851 Instruction Set.A-31
B-1 Exception Vector Assignments for the M68000 Family.B-2
C-1 Field Composition of an S-Record .C-1
C-2 ASCII Code ......C-5