ARM ARM Certifications EN0-001 Questions & Answers

• Question 11:

  In a single-processor system, which of these operations requires a barrier instruction to guarantee correct operation?

  A. Copying data from Flash to RAM

  B. Changing from one privileged mode to another

  C. Loading code into memory and then executing it

  D. Incrementing a RAM location that will be read by an interrupt handler

  Correct Answer: C

• Question 12:

  If the memory location 0x5000 contains 0Xffff0001, what is the value of r0 after the following instructions

  are executed?

  MOV r1, #0x5000

  LDRSH r0, [r1]

  ADD r0, r0, #1

  (Assume a little-endian memory system)

  A. 0x00000002

  B. 0xFFFF0002

  C. 0xFFFF0001

  D. 0xFFFFFFFE

  Correct Answer: A

• Question 13:

  Which TWO of the following interrupt types does a Generic Interrupt Controller (GIC) support? (Choose two)

  A. Interrupt from a private peripheral to a processor

  B. Interrupt from a processor to a private peripheral

  C. Interrupt from a shared peripheral to a processor

  D. Interrupt from a processor to a shared peripheral

  E. Interrupt from a private peripheral to a shared peripheral

  F. Interrupt from a shared peripheral to a private peripheral

  Correct Answer: AC

• Question 14:

  A software profiling tool records the address held in the Program Counter (PC) every 1 ms. The software function that resides at each recorded address can be determined by the profiling tool. The percentage of time spent in each function is calculated from the percentage of recorded addresses where each function is resident.

  Which one of the following statements is FALSE?

  A. The tool shows an estimate of the percentage of time spent in each function

  B. The tool identifies all functions executed by the application

  C. The function with the highest percentage is a good candidate for optimization

  D. The results will be more accurate on a processor running at 250 MHz. than one running at 2 GHz

  Correct Answer: B

• Question 15:

  Before execution: R0=0xFFFFFFFF R1 = ? EOR R0, R0, R1 If R0=0x00000000 after executing the EOR instruction above, what was the value in R1 before the

  instruction executed?

  A. 0x00000000

  B. 0xFFFFFFFF

  C. 0x11111111

  D. 0xAAAAAAAA

  Correct Answer: B

• Question 16:

  Which of these C99 keywords can be used to indicate that two arrays do not overlap?

  A. "pure"

  B. "volatile"

  C. "static"

  D. "restrict"

  Correct Answer: D

• Question 17:

  A Programmer's View CPU model usually provides:

  A. Cycle-accurate simulation of the CPU.

  B. Instruction-accurate simulation of the CPU.

  C. Simulation of user-defined memory-mapped peripherals.

  D. Cycle-accurate simulation of the cache and memory system.

  Correct Answer: B

• Question 18:

  To ensure optimum efficiency when programming in C, what is the recommended maximum number of arguments to be passed to a function?

  A. 1

  B. 4

  C. 7

  D. 8

  Correct Answer: B

• Question 19:

  Which of the following is TRUE for dynamically linked executables?

  A. They can contain unresolved relocations

  B. They contain the code and data for all libraries they use

  C. They are larger than an equivalent statically linked application

  D. They are designed to be run standalone with no other supporting software

  Correct Answer: A

• Question 20:

  In an experiment, the time taken for an application to complete a given task is measured using a stopwatch. Which THREE of the following make up the total time? (Choose three)

  A. The time spent waiting for I/O operations

  B. The time taken to download the program via the debugger

  C. The time taken for memory accesses

  D. The time taken for the CPU to execute instructions

  E. The time taken to compile the source code

  F. The time taken to perform instruction tracing

  Correct Answer: ACD