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S3C2501X
iii
Table of Contents
Chapter 1
Product Overview
1.1 Overview...........................................................................................................................................1-1
1.2 Features ............................................................................................................................................1-2
1.3 Block Diagram...................................................................................................................................1-4
1.4 Package Diagram ..............................................................................................................................1-5
1.5 Pin Assignment..................................................................................................................................1-6
1.6 Signal Description..............................................................................................................................1-12
1.7 Pad Type...........................................................................................................................................1-26
1.8 Special Registers...............................................................................................................................1-27
Chapter 2
Programmer's Model
2.1 Overview...........................................................................................................................................2-1
2.2 Switching State..................................................................................................................................2-1
2.2.1 Entering THUMB State...........................................................................................................2-1
2.2.2 Entering ARM State................................................................................................................2-1
2.3 Memory Formats................................................................................................................................2-2
2.3.1 Big-Endian Format..................................................................................................................2-2
2.3.2 Little-Endian Format...............................................................................................................2-2
2.4 Instruction Length ..............................................................................................................................2-3
2.5 Data Types ........................................................................................................................................2-3
2.6 Operating Modes ...............................................................................................................................2-3
2.7 Registers ...........................................................................................................................................2-4
2.7.3 The Relationship Between ARM and THUMB State Registers.................................................2-7
2.7.4 Accessing Hi-Registers in THUMB State.................................................................................2-8
2.8 The Program Status Registers...........................................................................................................2-8
2.8.1 The Condition Code Flags ......................................................................................................2-9
2.8.2 The Control Bits......................................................................................................................2-9
2.9 Exceptions.........................................................................................................................................2-11
2.9.1 Action on Entering an Exception.............................................................................................2-11
2.9.2 Action on Leaving an Exception..............................................................................................2-11
2.9.3 Exception Entry/Exit Summary...............................................................................................2-12
2.9.4 FIQ.........................................................................................................................................2-12
2.9.5 IRQ.........................................................................................................................................2-13
2.9.6 Abort ......................................................................................................................................2-13
2.9.7 Software Interrupt...................................................................................................................2-14
2.9.8 Undefined Instruction..............................................................................................................2-14
2.10 Exception Vectors............................................................................................................................2-14
2.10.1 Exception Priorities...............................................................................................................2-15
2.10.2 Not All Exceptions Can Occur at Once: ................................................................................2-15
2.11 Interrupt Latencies ...........................................................................................................................2-16
2.12 Reset...............................................................................................................................................2-16
2.13 Introduction for ARM940T................................................................................................................2-17
2.14 ARM940T Block Diagram.................................................................................................................2-18
2.15 About The ARM940T Programmer's Model......................................................................................2-19
2.15.1 Data Abort Model..................................................................................................................2-20
2.15.2 Instruction Set Extension Spaces..........................................................................................2-20
2.16 ARM940T CP15 Registers...............................................................................................................2-21
2.16.1 CP15 Register Map Summary ..............................................................................................2-21