Embedded-Hacking/WEEKS/WEEK01/QUIZ01.md

Week 1 Quiz: Embedded Systems Reverse Engineering Fundamentals

Instructions

Choose the best answer for each question. There is only one correct answer per question.

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Questions

Question 1

What is the primary characteristic that defines a microcontroller?

A) It only processes data at high speeds
B) It's a tiny computer with processor, memory, and storage on a single chip
C) It requires an external power supply to function
D) It can only run assembly code, not C programs

📖 Reference: Week 1, Part 1 – "What is a Microcontroller?"

Correct Answer: B

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Question 2

Which special register in the ARM Cortex-M33 is also known as the Link Register (LR)?

A) r13
B) r15
C) r14
D) r12

📖 Reference: Week 1, Part 2 – "The ARM Cortex-M33 Registers" (register table)

Correct Answer: C

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Question 3

In ARM systems, what happens to the Stack Pointer (SP) when you PUSH data onto the stack?

A) The SP value increases because data is added
B) The SP value decreases because the stack grows downward
C) The SP value stays the same
D) The SP value doubles to accommodate more data

📖 Reference: Week 1, Part 2 – "The Stack Pointer (r13 / SP)"

Correct Answer: B

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Question 4

What does XIP (Execute In Place) mean for the RP2350 microcontroller?

A) The processor must copy all code to RAM before execution
B) The processor can run code directly from flash memory without copying to RAM first
C) The processor can only execute code in debug mode
D) The processor executes instructions in parallel

📖 Reference: Week 1, Part 3 – "XIP - Execute In Place"

Correct Answer: B

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Question 5

At which memory address does program code start in flash memory for the RP2350?

A) 0x00000000
B) 0x20000000
C) 0x10000000
D) 0xFFFFFFFF

📖 Reference: Week 1, Part 3 – "XIP - Execute In Place" (Key Memory Address: 0x10000000)

Correct Answer: C

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Question 6

What is the purpose of the Program Counter (PC) register?

A) It counts how many times a program has run
B) It stores the total number of instructions executed
C) It points to the next instruction the processor will execute
D) It keeps track of how much time has elapsed

📖 Reference: Week 1, Part 2 – "The Program Counter (r15 / PC)"

Correct Answer: C

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Question 7

Which GDB command is used to display the disassembled assembly code for the current function?

A) info assembly
B) show code
C) disas
D) list asm

📖 Reference: Week 1, Part 4 – "Disassembling with disas"

Correct Answer: C

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Question 8

Why do we start with ELF (.elf) files instead of stripped binary (.bin) files when learning reverse engineering?

A) ELF files are smaller and faster to load
B) ELF files contain symbols like function names that make analysis easier
C) Binary files cannot be analyzed by Ghidra
D) ELF files run faster on the Pico 2

📖 Reference: Week 1, Part 5 – "Why We Start with .elf Files"

Correct Answer: B

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Question 9

In the hello-world program, what assembly instruction creates the infinite loop?

A) push {r3, lr}
B) bl stdio_init_all
C) b.n (branch to earlier instruction)
D) ldr r0, [pc, #8]

📖 Reference: Week 1, Part 4 – "Disassembling with disas" (the disas output showing b.n 0x1000023a)

Correct Answer: C

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Question 10

What does the stdio_init_all() function do in the hello-world program?

A) It compiles the code into assembly
B) It initializes standard I/O for USB CDC and UART communication
C) It creates an infinite loop
D) It loads the program into flash memory

📖 Reference: Week 1, Part 3.5 – "Initializing Standard I/O"

Correct Answer: B

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Answer Key

1. B - A microcontroller is a tiny computer with processor, memory, and storage on a single chip
2. C - Register r14 is the Link Register (LR)
3. B - The SP decreases because the stack grows downward in memory
4. B - XIP allows the processor to run code directly from flash memory
5. C - Program code starts at 0x10000000 in flash memory
6. C - The PC points to the next instruction to be executed
7. C - The disas command displays disassembled assembly code
8. B - ELF files contain symbols that make learning and analysis easier
9. C - The branch instruction b.n creates the infinite loop
10. B - stdio_init_all() initializes standard I/O for USB and UART

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Scoring Guide

• 10 correct: Excellent! You have a strong grasp of Week 1 concepts
• 8-9 correct: Very good! Review the topics you missed
• 6-7 correct: Good start. Go back and review the key concepts
• 5 or fewer: Review the Week 1 material again and try the practice exercises

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Topics Covered

This quiz tests your understanding of:

• Microcontroller basics and the RP2350
• ARM Cortex-M33 registers (general purpose and special registers)
• Stack behavior and memory layout
• XIP and memory addresses
• GDB debugging commands
• Assembly instructions and program flow
• Static analysis with Ghidra and ELF files
• The hello-world program structure