Motorola MC68030 User Manual page 19

LIST OF ILLUSTRATIONS (Continued)
Figure
Number
8-8 RTE Instruction for Throwaway Four-Word Frame . . . . . . . . . . . . . . . . . . 8-26
8-9 Special Status Word (SSW) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-28
9-1 MMU Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-3
9-2 MMU Programming Model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-4
9-3 Translation Table Tree . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-5
9-4 Example Translation Table Tree . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-7
9-5 Example Translation Tree Layout in Memory. . . . . . . . . . . . . . . . . . . . . . . 9-8
9-6 Derivation of Table Index Fields. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-9
9-7 Example Translation Tree Using Different Format Descriptors . . . . . . . . . 9-12
9-8 Address Translation General Flowchart . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-14
9-9 Root Pointer Descriptor Format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-23
9-10 Short-Format Table Descriptor. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-24
9-11 Long-Format Table Descriptor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-24
9-12 Short-Format Page Descriptor and Short-Format Early
Termination Page Descriptor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-25
9-13 Long-Format Early Termination Page Descriptor. . . . . . . . . . . . . . . . . . . . 9-25
9-14 Long-Format Page Descriptor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-26
9-15 Short-Format Invalid Descriptor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-26
9-16 Long-Format Invalid Descriptor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-27
9-17 Short-Format Indirect Descriptor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-27
9-18 Long-Format Indirect Descriptor. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-28
9-19 Simplified Table Search Flowchart. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-29
9-20 Five-Level Table Search . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-31
9-21 Example Translation Tree Using Contiguous Memory. . . . . . . . . . . . . . . . 9-35
9-22 Example Translation Tree Using Indirect Descriptors . . . . . . . . . . . . . . . . 9-36
9-23 Example Translation Tree Using Shared Tables . . . . . . . . . . . . . . . . . . . . 9-38
9-24 Example Translation Tree with Nonresident Tables. . . . . . . . . . . . . . . . . . 9-39
9-25 Detailed Flowchart of MMU Table Search Operation. . . . . . . . . . . . . . . . . 9-41
9-26 Table Search Initialization Flowchart . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-42
9-27 ATC Entry Creation Flowchart . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-42
9-28 Limit Check Procedure Flowchart . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-43
9-29 Detailed Flowchart of Descriptor Fetch Operation . . . . . . . . . . . . . . . . . . . 9-44
9-30 Logical Address Map Using Function Code Lookup . . . . . . . . . . . . . . . . . 9-45
9-31 Example Translation Tree Using Function Code Lookup. . . . . . . . . . . . . . 9-46
9-32 Example Translation Tree Structure for Two Tasks . . . . . . . . . . . . . . . . . . 9-47
9-33 Exmple Logical Address Map with Shared Supervisor
and User Address Spaces . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-49
9-34 Exmple Translation Tree Using S and WP Bits to Set Protection . . . . . . . 9-50
9-35 Root Pointer Register (CRP, SRP) Format . . . . . . . . . . . . . . . . . . . . . . . . 9-54
9-36 Translation Control Register (TC) Format . . . . . . . . . . . . . . . . . . . . . . . . . 9-54
9-37 Transparent Translation Register (TT0 and TT1) Format . . . . . . . . . . . . . 9-57
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Title
MC68030 USER'S MANUAL
Page
Number
MOTOROLA