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TABLE OF CONTENTS (Continued)
Paragraph
Number
Page
Number
Title
xiv
MPC801
USER’S MANUAL
MOTOROLA
Section 14
Endian Modes
14.1
14.2
14.3
14.4
Little-Endian System Features ...........................................................14-2
Big-Endian System Features .............................................................14-4
PowerPC Little-Endian System Features ...........................................14-4
Setting the Endian Mode Of Operation ..............................................14-5
Section 15
Memory Controller
15.1
15.2
15.2.1
15.2.1.1
15.2.1.2
15.2.1.3
15.2.1.4
15.2.1.5
15.2.2
15.2.2.1
15.2.2.2
15.2.2.3
15.2.2.4
15.2.2.5
15.2.3
15.2.3.1
15.2.3.2
15.2.3.3
15.2.3.4
15.2.3.5
15.2.3.6
15.2.3.7
15.2.3.8
15.2.3.9
15.2.3.10
15.2.3.11
15.2.3.12
15.2.3.13
15.3
15.4
15.4.1
15.4.2
Features .............................................................................................15-1
Basic Architecture ..............................................................................15-3
Registers Associated with the Memory Controller ...................15-6
8-, 16-, and 32-Bit Port Size Configuration ...................15-7
Write-Protect Configuration ..........................................15-7
Address and Address Space Checking ........................15-7
Parity Generation and Checking ...................................15-7
Transfer Error Acknowledge Generation ......................15-7
The General-Purpose Chip-Select Machine ............................15-7
Programmable Wait State configuration .....................15-13
Extended Hold Time on Read Accesses ....................15-13
Global Chip-Select Operation .....................................15-15
SRAM interface ..........................................................15-16
GPCM External Asynchronous Master Support .........15-17
User-Programmable Machines ..............................................15-19
RAM Word Structure and Timing Specification ..........15-25
CS Signals ..................................................................15-28
Byte Select Signals .....................................................15-29
General-Purpose Signals ...........................................15-30
Loop Control Signal ....................................................15-31
Exception Handling .....................................................15-31
Address Control Signals .............................................15-32
The Disable Timer Mechanism ...................................15-35
Transfer Acknowledge And Data Sample Control ......15-36
The WAIT Mechanism ................................................15-36
Location of UPM Start Addresses ..............................15-39
Example DRAM Interface ...........................................15-39
Extended Data-Out Interface Example .......................15-52
External Master Support ..................................................................15-59
Programming the Memory Controller ...............................................15-68
Memory Status Register .........................................................15-68
Memory Periodic Timer Prescaler Register ...........................15-69