Exam 1 Study Assembly

High-level languages have a one-to-one relationship with Assembly language. (T/F)

(False) High-level languages have a one-to-many relationship with Assembly language.

x86 processors running under 32-bit and 64-bit versions of Microsoft Windows

True

An effective way to explain how a computer's hardware and software are related is called the virtual machine concept.

True

Which utility programs below is NOT an assembler?:

MASM

 

NASM

 

GAS

 

All answers are correct

 

TASM

All answers are correct!

To run a high-level language into a native machine language, we may either interpret or translate.

True

In this course, we will use Microsoft Visual Studio as the IDE and run on the Windows Systems ONLY.

True

Assembly language is portable as long as running on the same hardware device (same type processor).

(False) Assembly language is portable as long as running on the same hardware device (same type processor).

Which statement below is NOT true?

 

a doubleword is 2 bytes

 

1 byte = 8 bits

 

The MSB of a negative signed binary number is 1

 

The LSB of an odd number is always 1

a doubleword is 2 bytes

The control unit (CU) coordinates the sequencing of steps involved in executing machine instructions.

True

In Real-address mode, multiple programs can run at the same time, but they can only address physical memory (from the hardware devices)

(False) They can access virtual memory (System memory) too

The arithmetic logic unit performs addition, subtraction, multiplication, and division operations.

False

The Zero flag is clear when the result of an arithmetic operation is zero.

(False) The Zero flag is clear when the result of an arithmetic operation is NOT zero.

The lower half of the RCX register is called EBX.

(False) The lower half of the RCX register is called ECX.

In 64-bit mode, you can use three more general-purpose registers than in 32-bit mode.

False

The Carry flag reflects the status of an unsigned arithmetic operation.

True

When running in native 64-bit mode, processors do not support 16-bit Real Mode.

True

Data travels along a bus with n bits running in parallel, where the bus is n bits wide.

True

The Basic Input-Output System is a collection of low-level subroutines that communicate directly with hardware devices.

True

An identifier in assembly language may only contain letters and digits.

False

The EQU directive permits a constant to be redefined at any point in a program.

(False) The EQU directive can't be redefined at any point in a program.

An object file is commonly executable by the operating system. 

(False) An object file isn’t quite ready to execute.

A string literal must be enclosed in double quotes.

(False) A string literal can be enclosed in single or double quotes.

A code name must end with a colon (:)

True

A listing file contains a copy of the program's source code, the numeric address of each instruction, and a symbol table. It also display the machine code bytes for the program.

True

The .DATA directive must always occur before the .CODE directive.

False

Identifiers are by default, case sensitive.

(False) Identifiers are NOT case sensitive.

In the following statement, EAX is called the source operand:

mov EBX, EAX

True

The SDWORD directive is used when defining signed 32-bit integers.

True

What is the EAX value after the following instruction?

.data
arrayD DWORD 10h, 20h, 30h, 40h

.code
MOV EAX, [arrayD + 3 ]

00002000h

When you use MOVZX to move a 16-bit or an 8-bit memory operand into a 64-bit register, the upper bits of the destination operand are cleared.

True

The SUB instruction requires the source operand to be no larger than the destination operand.

False

Write one instruction to move the value of  30h from the following data into a register

.data
arrayW WORD 10h, 20h, 30h, 40h

mov ax, [arrayW + 4]

Which instruction below can NOT  move the value of  30h from the following data into EAX?

.data
arrayW WORD 10h, 20h, 30h, 40h

MOV EAX, [arrayW + 4]

Write one instruction to make 10h below become 11h

.data
arrayW WORD 10h, 20h, 30h, 40h

add arrayW, 1

INC arrayW

ADD ARRAYW, 1

ADD arrayW, 1

The MOV instruction permits a move between two 8-bit memory operands, as long as one operand uses the BYTE PTR operator.

(False) The MOV instruction should contain at least one register.

Which status flag is set after the following instructions?

MOV  AX, 0FFFFh
INC  AX

Zero Flag

The SAHF instruction copies the CPU status flags to the AH register.

False

To move -4 into EDX register, we should do, 

movsx EDX, -4

(False) to move a constant value to the register, just do MOV instead of MOVSX

 

mov EDX, -4

Suppose BX and DX both contain positive integers. If adding them produces a negative result, the Overflow flag will be set.

True

The following instruction will assemble correctly: 

DEC  BYTE PTR [edi]

True

The following statement will assemble without errors:

mov DWORD PTR [eax], 1234h

True

The following instructions will set the Overflow flag:

mov al, D7h

add al, 75h

(False) To add a positive integer and a negative integer will never set the overflow flag

The Overflow flag will never be set when subtracting a positive integer from a negative integer.

False

The following instructions will set the Overflow flag:

mov al, +125

sub  al, -5

True

Given the following statements, what are the values in AX and ECX?

    MOV AX, 0
    MOV ECX, 10
L1: INC AX
    LOOP L1

AX = 10

ECX = 0

In the 64-bit environment, the ECX is the counter used in a LOOP instruction.

(False) In the 64-bit environment, the RCX is the counter used in a LOOP instruction.

If AL contains +127 and you add 3 to AL, the carry flag will be set.

False

Given the following statements, what are the values in AX and ECX?

    MOV AX, 0
    MOV ECX, 10
L1: INC AX
    JMP L1

AX = unknown

ECX = 10

In a stack, the first value pushed on a stack is the last one to be removed.

True

A nested procedure call occurs when a called procedure calls another procedure before the first procedure returns.

True

The PUSH instruction copies a value from the stack to an operand before decrementing the stack pointer.

(False) It is the pop operation.

The runtime stack is supported by the computer's processor.

True

The EBP register points to the last value pushed on the runtime stack.

(False) The ESP register points to the last value pushed on the runtime stack.

When the POP instruction executes, the ESP register is incremented after the value it points to is copied from the stack.

True

In 32-bit mode, immediate values pushed on the stack are always 32 bits long.

True

The WriteDec procedure does not display a plus sign.

True

The USES operator, coupled with the PROC directive, lets you list the names of all registers modified within a procedure, and the original values will be pushed into and pop from the run-time stack.

True

By default, labels are visible only within the procedure in which they are declared.

True

From Irvine 32 library, which procedure below we should use to read a signed integer from the console input?

ReadInt

From Irvine 32 library, which register below we should use to refer to the location of the string we wanted to display in the console by using the WriteString procedure?

EDX

From Irvine 32 library, which procedure below we use to display the registers and status flag values in the console?

DumpRegs

From Irvine 32 library, which register below we should use to refer to the offset of the array we wanted to display in the console by using the DumpMem procedure?

ESI

From Irvine 32 library, which register below we should use to save the background and foreground color values by using the SetTextColor procedure?

EAX