COE121 - Q3 (Multiple Choice)

What is the ending address of a memory segment if the segment register contains 3456H? a. 4455H b. 445FFH c. 44FFFH d. 3456FH

a. 4455FH

31-bit microprocessors operating in protected mode could address up to a. 640MB b. 1GB c. 4GB d. 16GB

c. 4GB

The physical address accessed by the segment:offset combination A359:B3FD a. B098C b. 15756 c. BE329 d. AE98D

d. AE98D

Real mode memory addressing is the ONLY memory management mode available to a. 8086/8088 b. 80286 c. 80386 d. both a and b (8086/8088 and 80286)

*c. 80386

If a descriptor has Base = 23000000H, Limit = 012FFH and G = 1, the described segment ends at a. 230012FFH b. 2300FFFF c. 242FFFFFH d. none of the choices

*d. none of the choices

This addressing mode uses a register to hold the actual address that identifies either the source or the destination to be used in the data transfer. a. Indirect b. Register relative c. Direct d. Immediate

A. Indirect

The addressing mode in which the effective address of the memory location is visibly part of the instruction. a. Implied Mode b. Immediate Mode c. Direct Mode d. Register Mode

C. Direct Mode

The minimum distance possible between two overlapping 64-kB memory segments is a. 16 bytes b. 24 bytes c. 30 bytes d. 36 bytes

a. 16 bytes

In Real Mode, a memory segment that begins at 10000H will end at a. 1FFFFH b. 1F000H c. FFFFFH d. 2FFFFH

a. 1FFFH

Given CS = 2000H and IP = 1000H, find the memory address of the next instruction executed by the microprocessor. a. 21000H b. 22000H c. 2100H d. 12000H

a. 21000H

Address is referred to _____ when the processor's address bus is formed by some combination of segment register and an additional numerical offset. a. Effective Address b. Immediate Addressing c. Register Addressing d. Base Addressing

a. Effective Address

Which of the following examples is an Immediate Addressing Mode? a. MOV AL, FFH b. MOV AX, [BX+4] c. MOV [DI-8], BL d. MOV [500H], AL

a. MOV AL, FFH

The DOS operating system requires the processor to operate in _____ mode. a. real b. protected c. flat d. unconventional

a. real

It defines the beginning address of any 64k-byte memory segment. a. segment address b. offset address c. base address d. return address

a. segment address

A processor running in real-mode is limited to use _____ of its address bus to access the memory system a. 16-bit b. 20-bit c. 24-bit d. 36-bit

b. 20-bit

8026 could be operated in protected mode but with only have _____ for address bus. a. 20-bit b. 24-bit c. 32-bit d. 36-bit

b. 24-bit

MOV AX, [BX+4] is a sample of which type of addressing? a. Register Indirect b. Register Relative c. Base-plus-index d. Immediate

b. Register Relative

The instructor MOV DS:[2000H], AL a. has mixed sizes operands b. copied byte-size data in AX to the memory c. is an example of immediate addressing mode d. is illegal, not allowed

b. copied byte-size data in AX to the memory

If SI = 1000H, what does MOV [SI], BH do? a. reads byte of data from memory location 1000H b. wirte byte of data from BH into memory location 1000H c. illegal, only DI can be used between []'s d. illegal, mixed register sizes

b. writes byte of data from BH into memory location 1000H

Which register contains the location where the next instruction in the code segment should be fetched? a. SP b. SI c. IP d. DI

c. IP

One must never use the segment registers as data registers to hold arbitrary values because: a. They should only contain register addresses b. They should only contain ending addresses c. They should only contain segment addresses d. They should only contain indirect addresses

c. They should only contain segment addresses

Which of the following is an example of Relative program addressing? a. JMP [2] b. JMP [0123] c. both the above d. none of the choices

c. both the above (JMP [2] and JMP [0123])

It selects any location within the 64K byte memory segment. a. Base b. limit c. offset address d. segment address

c. offset address

What is the starting and ending address of the segment located by the segment register value, 1000H? a. 10FFFH, FFFFFH b. 10000H, 10FFFH c. 01000H, 01FFFH d. 10000H, 1FFFFH

d. 10000H, 1FFFFH

CS contains 2001H and IP contains 007CH, which physical memory location is accessed for the next instruction a. 20010H b. 3000FH c. 2007DH d. 2008CH

d. 2008CH

TI=0 indicates that TI is _____. a. A local descriptor table b. A real descriptor table c. Not a descriptor table d. A global descriptor table

d. A global descriptor table

This is an example of register Indirect Addressing Mode a. MOV CX, AX b. MOV AL, FFH c. MOV DX, [BX+04] d. MOV AX, [BX]

d. MOV AX, [BX]

Which of the following segment:offset combinations point to a common physical memory address? a)A1B2:000C, b)A1B0:200C, c)A1B0:002C, d)A1B1:001C a. a and b b. b and c c. a, b and c d. a, c and d

d. a, c and d (A1B2:000C, A1B0:002C and A1B1:001C)

Which of the following is an example of Relative program addressing? a. RPL<DPL b. RPL=DPL c. RPL>DPL d. b and c (RPL=DPL and RPL>DPL)

d. b and c (RPL=DPL and RPL>DPL)

In protected mode, access to the segment is allowed if a. RPL=DPL b. RPL>DPL c. RPL<DPL d. both a and b

d. both a and b (RPL=DPL and RPL>DPL)

In protected mode memory, protection implemented by restricting access to memory segments through a. privilege levels b. access rights c. granularity d. both a and b (privilege levels and access rights)

d. both a and b (privilege levels and access rights)

The first 1Mbyte of memory is called the _____ a. unreal mode b. conventional c. real mode d. both b and c

d. both b and c (conventional and real mode)