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TABLE OF CONTENTS (Continued)
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Number
Page
Number
Title
xii
MPC801
USER’S MANUAL
MOTOROLA
11.8
11.8.1
11.8.1.1
11.8.2
11.8.3
11.8.4
11.9
Manipulating the TLB .......................................................................11-30
Reloading the TLB .................................................................11-30
Translation Reload Examples .....................................11-31
Controlling the TLB Replacement Counter ............................11-32
Invalidating the TLB ...............................................................11-32
Loading the Reserved TLB Entries ........................................11-32
Requirements For Accessing The Memory Management
Unit Control Registers ......................................................................11-32
Section 12
System Interface Unit
12.1
12.2
12.3
12.3.1
12.3.2
12.3.2.1
12.3.2.2
12.3.2.3
12.3.2.4
12.4
12.5
12.6
12.7
12.8
12.9
12.10
12.10.1
12.11
12.12
12.12.1
12.12.1.1
12.12.1.2
12.12.1.3
12.12.1.4
12.12.1.5
12.12.2
12.12.2.1
12.12.2.2
12.12.2.3
12.12.2.4
Features .............................................................................................12-2
System Configuration and Protection .................................................12-2
Configuring the System ......................................................................12-4
Configuring the Interrupt ..........................................................12-4
Priority of the Interrupt Sources ...............................................12-5
Programming the Interrupt Controller ...........................12-6
SIU Interrupt Mask Register .........................................12-7
SIU Interrupt Edge Level Mask Register ......................12-8
SIU Interrupt Vector Register .......................................12-9
The Bus Monitor ...............................................................................12-10
The PowerPC Decrementer .............................................................12-10
The PowerPC Timebase ..................................................................12-11
The Real-Time Clock .......................................................................12-11
The Periodic Interrupt Timer ............................................................12-12
The Software Watchdog Timer ........................................................12-13
Freeze Operation .............................................................................12-15
Low-Power Stop Operation ....................................................12-15
Multiplexing the System Interface Unit Pins .....................................12-16
Programming the System Interface Unit ..........................................12-17
System Configuration and Protection Registers ....................12-17
SIU Module Configuration Register ............................12-17
Internal Memory Map Register ...................................12-20
System Protection Control Register ...........................12-21
Software Service Register ..........................................12-22
Transfer Error Status Register ....................................12-22
System Timer Registers .........................................................12-23
Decrementer Register ................................................12-23
Timebase Register .....................................................12-24
Timebase Reference Register ....................................12-24
Timebase Control and Status Register .......................12-25