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11/3/95
SECTION 1: OVERVIEW
UM Rev.1.0
vi
MC68349 USER’S MANUAL
MOTOROLA
TABLE OF CONTENTS (Continued)
Paragraph
Page
Number
Title
Number
3.6
Bus Arbitration ...................................................................................... 3-52
3.6.1
Bus Request ...................................................................................... 3-55
3.6.2
Bus Grant .......................................................................................... 3-56
3.6.3
Bus Grant Acknowledge .................................................................... 3-56
3.6.4
Bus Arbitration Control ...................................................................... 3-56
3.6.5
Show Cycles...................................................................................... 3-57
3.7
Reset Operation .................................................................................... 3-59
Section 4
System Integration Module
4.1
Module Overview .................................................................................. 4-1
4.2
Module Operation.................................................................................. 4-2
4.2.1
Module Base Address Register Operation ........................................ 4-2
4.2.2
System Configuration and Protection Operation ............................... 4-3
4.2.2.1
System Configuration .................................................................... 4-5
4.2.2.2
Internal Bus Monitor....................................................................... 4-6
4.2.2.3
Double Bus Fault Monitor .............................................................. 4-6
4.2.2.4
Spurious Interrupt Monitor ............................................................. 4-6
4.2.2.5
Software Watchdog ....................................................................... 4-7
4.2.2.6
Periodic Interrupt Timer ................................................................. 4-7
4.2.2.6.1
Periodic Timer Period Calculation .............................................. 4-8
4.2.2.6.2
Using the Periodic Timer as a Real-Time Clock......................... 4-9
4.2.2.7
Simultaneous Interrupts by Sources in the SIM49 ......................... 4-9
4.2.3
Clock Synthesizer Operation ............................................................. 4-9
4.2.3.1
Phase Comparator and Filter......................................................... 4-13
4.2.3.2
Frequency Divider. ......................................................................... 4-13
4.2.3.3
Clock Control ................................................................................. 4-16
4.2.4
Chip Select Operation ....................................................................... 4-16
4.2.4.1
Programmable Features ................................................................ 4-17
4.2.4.2
Global Chip Select Operation ........................................................ 4-18
4.2.5
External Bus Interface Operation ...................................................... 4-18
4.2.5.1
Port A ............................................................................................. 4-18
4.2.5.2
Port B ............................................................................................. 4-19
4.2.6
Low-Power Stop ................................................................................ 4-20
4.2.7
Freeze ............................................................................................... 4-21
4.3
Programming Model .............................................................................. 4-21
4.3.1
Module Base Address Register (MBAR) .......................................... 4-23
4.3.2
System Configuration and Protection Registers................................ 4-24
4.3.2.1
Module Configuration Register (MCR) ........................................... 4-24
4.3.2.2
Identification Register (IDR)........................................................... 4-26
4.3.2.3
Autovector Register (AVR)............................................................. 4-26
4.3.2.4
Reset Status Register (RSR) ......................................................... 4-27