Raspberry Pi Operating System Assembly Language

Using This eBook
	Acknowledgements
	Dedication
1. Introduction
	Imagination Unlimited
	Start Experimenting
	GNU C Compiler
	Learn by Example
	What Will You Learn?
	Fourth Edition and Compatibility
	Raspberry Pi OS
	What About 64-bit?
	Keyboard Computing
	The Significance of ARM
	Raspberry Pi Through the Ages
	Compute Modules
	Notation in Use
	Table Terminology
	Centre for Computing History
	Companion Website and Free Books
2. Starting Out
	Numbers with Meaning
	ARM Instructions
	The Transformation Process
	Why Machine Code?
	Language Levels
	Into Orbit
	RISC and Instruction Sets
	Assembler Structure
	Error Of Your Ways
	Cross Compilers
	The Raspberry Pi ARM Chips(s)
3. First Time Out
	The Command Line
	Creating A Source File
	Come to the Execution
	Assembler Errors
	The Components
	Lack of _start
	Linking Files
	Tidying Up
	A Comment on Comments
	Geany Programmer’s Editor
4. Bits of a RISC Machine
	Binary to Decimal
	Binary to Hex
	Hex to Decimal and Back
	Binary Addition
	Subtraction
	Twos Complement Numbers
	When Twos Don’t Add Up
	Desktop Calculator
5. ARM Arrangements
	Word Lengths
	Byte and Word Accessed Memory
	Registers
	R15 - Program Counter
	Current Program Status Register
	Bits and Flags
	Setting Flags
	S Suffix
	R14: The Link Register
	R13: The Stack Pointer
6. Data Processing
	Addition Instructions
	Subtraction
	Multiplication
	Divide Arrives
	Move Instructions
	Compare Instructions
	Ordering Numbers
7. ROS Ins and Outs
	SWI and SVC Commands
	Writing to the Screen
	Reading from the Keyboard
	eax and Others
8. Logical Operations
	Logical AND
	Logical OR
	Logical EOR
	Logical Instructions
	ORR to Convert Character Case
	Bit Clear with BIC
	Flag Tests
	System Call Registers
9. Conditional Execution
	Single Flag Condition Codes
		EQ: Equal
		NE: Not Equal
		VS: Overflow Set
		VC: Overflow Clear
		MI: Minus Set
		PL: Plus Clear
		CS: Carry Set (HS: Higher or Same)
		CC: Carry Clear (LO: Lower)
		AL: Always
		NV: Never
	Multiple Flag Condition Code
		HI: Higher (Unsigned)
		LS: Lower Than or Same (Unsigned)
		GE: Greater or Equal (Signed)
		LT: Less Than (Signed)
		GT: Greater Than (Signed)
		LE: Less Than or Equal To (Signed)
	Mixing the S Suffix
10. Branch and Compare
	Branch Instructions
	The Link Register
	Using Compare Instructions
	Compare Forward Thinking
	Branch Exchange
11. Shifts and Rotates
	Logical Shifts
	Logical Shift Right
	Arithmetic Shift Right
	Rotations
	Extended Rotate
	Uses of Shifts and Rotates
	Immediate Constant Range
	Top Move
12. Smarter Numbers
	Long Multiplication
	Long Accumulation
	Division and Remainder
	Smarter Multiplication
	Much More Inside
13. Program Counter R15
	Pipelining
	Calculating Branches
14. Debugging with GDB
	Frozen Cases
	Assembling for GDB
	The Disassembler
	Breakpoints
	Breakpoint Labels
	Memory Dump
	Shortcuts
	GDB Make Options
15. Data Transfer
	ADR Directive
	Indirect Addressing
	ADR and LDR
	Pre-Indexed Addressing
	Accessing Memory Bytes
	Address Write Back
	Post-Indexed Addressing
	Byte Conditions
	PC Relative Addressing
16. Block Transfer
	Write Back
	Block Copy Routine
17. Stacks
	Push and Pull
	Stack Growth
	Stack Application
	Framed Work
	Frame Pointer
18. Directives and Macros
	Data Storage Directives
	Aligning Data
	Macros
	Including Macros
19. File Handling
	File Permissions
20. Using libc
	Using C Functions in Assembler
	Source File Structure
	Investigating the Executable
	Number Input with Scanf
	Getting This Information
21. Writing Functions
	Function Standards
	More Than Three
	Preserving Links and Flags
	Robust Print Routines
23. GPIO Functions
	Memory Mapping
	The GPIO Controller
	GPIO In and Outs
	Building the Code
	Other GPIO Functions
	GPIO Pins Explained
24. Floating-Point
	VFP Architecture
	The Register File
	Managing and Printing
	Assembling and Debugging VFP with GDB
	Load, Store and Move
	Precision Conversion
	Vector Arithmetic
25. VFP Control Register
	Conditional Execution
	Scalar and Vector Operations
	Which Type of Operator?
	Len and Stride
26. Neon
	Neon Assembler
	Neon Instructions and Data Types
	Addressing Modes
	VLD and VST in their Stride
	Load of Others
	Neon Intrinsic
	Neon Arrays
	Order Correctly
	Matrix Math
	Multi Matrix
	Macro Matrix Example
27. Thumb Code
	Differences
	Assembling Thumb
	Accessing High Registers
	Stack Operators
	Single and Multi-Register
	Functions in Thumb
	ARMv7 Thumb Instructions
28. Unified Language
	Thumb Changes
	New A32 Instructions
	Compare by Zero
	Assembling UAL
29. Exception Handing
	Modes of Operation
	Vectors
	Register Arrangements
	Exception Handling
	MRS and MSR
	Interrupts When?
	Your Interrupt Decisions
	Returning from Interrupts
	Writing Interrupt Routines
30. System on a Chip
	The ARM Chip & Instruction Sets
	Co-processors
	Pipeline
	Memory & Caches
	The GPU
	ARMv8 Overview
	Raspberry Pi OS 64-Bit
	In Summary
	Archimedes Principle
A. ASCII Character Set
B. ARM Instruction Set
C. Raspbian Syscalls