Raspberry Pi 4 Architecture and ARM Assembly Programming

These flashcards cover key concepts and definitions related to Raspberry Pi 4 architecture, the ARM assembly programming environment, and associated terminology.

ARM 8 Cortex-A72

Architecture used in the Raspberry Pi 4.

Broadcom (BCM) 2711

Processor used in the Raspberry Pi 4.

RTC

Real Time Clock, an important function missing in the RP4.

Clock Speed of RP4

1.5 GHz.

Harvard Architecture

Takes more area to implement, has highest performance, used for on-chip cache, allows simultaneous instruction and data access.

Von Neumann Architecture

Typically used for main memory, most optimal for processor pinout.

Program Counter (PC)

Special register in ARM CPU architecture that stores the address of the next instruction.

Binary Opcode

Language that the ARM8 processor runs.

ARM RISC architecture

Characterized by Load/Store architecture and 32-bit instructions with a CPI of 1.

Flowcharts

Symbolic representations, better for smaller code jobs.

Pseudo Code

Natural text used for larger code jobs, flexible level of detail.

Assembler

Primary function is to convert readable assembly to binary machine code.

Makefile

Helps with file management, uses files needed based on changes, automates software building.

Binary digit (Bit)

Can be 1 or 0.

Nibble

4 bits.

Byte

8 bits.

Half Word

16 bits.

Word

32 bits.

Decimal to Binary Conversion of 220

Results in 11011100 (8-bit unsigned).

Hexadecimal representation of 63789

F92D (16-bit unsigned).

Hex FFFF

Represents -1 in 16-bit signed decimal.

Hex FF01

Represents -255 in 16-bit signed decimal.

CPSR

Register that holds the flags.

Branch Instruction

Changes the program counter if taken.

Flags: N Flag

Set if the MSB (sign bit) is set.

Flags: Z Flag

Set if the result is zero.

Flags: C Flag

Set on addition if overflow, on subtraction if no borrow.

Flags: V Flag

Set if a positive number looks negative or vice versa.

Little Endian

Default addressing for LSB/MSB priority in ARM8.

ARM8 Addressing Modes

Immediate, Register Indirect, Scaled Register, Register Direct.

ARM Instructions Boundary

Always on 4-byte boundaries.

Conditions based on Flags

Various conditions indicated by sets of Z, C, N, V flags.

Pseudo Instruction

Instruction that simplifies cumbersome operations.

Directives in Assembly

Commands like .EQU, .REQ, .byte, .half, .space, etc.