Assembly Quiz 2
In real-address mode, convert the following hexadecimal segment-offset address to a linear address: 0950:0100
09600h
In real-address mode, convert the following hexadecimal segment-offset address to a linear address: 0CD1:02E0
0CFF0h
What is the duration of a single clock cycle in a 3-GHz processor?
3.33x10^-10
In MASM's flat segmentation model, how many bits hold the address of an instruction or variable?
32 bits
How many bits long are the FPU data registers?
80 bits
What characteristics distinguish BIOS-level input/output?
BIOS functions communicate directly with the system hardware. They are independent of the operating system
What are the main differences between Wi-Fi and Bluetooth?
Bluetooth is a wireless communication protocol for exchanging small amounts of data over short distances. It is commonly used with mobile devices such as cell phones and PDAs. Wi-Fi devices operate at a greater speed and capacity than Bluetooth. Wi-Fi devices often communicate with each other when in the range of a wireless network.
Describe the CISC design approach.
CISC means complex instruction set. A large collection of instructions, some of which perform sophisticated operations that might be typical of a high-level language
Name all six segment registers
CS, DS, ES, FS, GS, SS
Which flag is set when the result of an unsigned arithmetic operation is too large to fit into the destination?
Carry
The central processor unit (CPU) contains registers and what other basic elements?
Control Unit, Arithmetic Logic Unit, and the clock.
Why does memory access take more machine cycles than register access?
Conventional memory is outside the CPU and it responds more slowly to access requests. Registers are hard-wired inside the CPU.
The central processor unit is connected to the rest of the computer system using what three buses?
Data, Address, and Control buses.
During which stage of the instruction execution cycle is the program counter incremented?
During the fetch step.
Name four types of RAM mentioned in this chapter.
Dynamic RAM, Static RAM, Video RAM, and CMOS RAM
Name all eight 32-bit general-purpose registers.
EAX, EBX, ECX, EDX, ESI, EDI, ESP, EBP
Besides the stack pointer (ESP), what other register points to variables on the stack?
EBP
Which two additional steps are required in the instruction execution cycle when a memory operand is used?
Fetch and Store
What are the three basic steps in the instruction execution cycle?
Fetch, decode, execute
When a program runs, what information does the OS read from the filename's disk directory entry?
Filename, file size, and starting location on the disk. Most directories also store the file's last modification date and time.
Which part of the CPU performs floating-point arithmetic?
Floating-Point Unit
What is the range of addressable memory in protected mode?
GByte 0 to FFFFFFFFh
Why do game programs often send their sound output directly to the sound card's hardware ports?
Game programs often try to take advantage of the latest features in specialized sound cards. It should be noted that MS-DOS game applications were more prone to do this than games running under MS-Windows. In fact, Windows-NT, 2000, and XP all prevent applications from directly accessing system hardware.
In the flat segmentation model, which table contains pointers to at least two segments?
Global descriptor table
In protected mode, which table contains pointers to memory segments used by a single program?
Local descriptor table
What special purpose does the ECX register serve?
Loop counter.
What is the range of addressable memory in real-address mode?
MByte 0 to FFFFFh
Name at least four CPU status flags.
Most common: Carry, Sign, Zero, Overflow. Less common: Auxiliary Carry, Parity.
Why are device drivers necessary, given that the BIOS already has code that communicates with the computer's hardware?
New devices are invented all the time with capabilities that were often not anticipated when the BIOS was written.
Is it likely that the BIOS for a computer running MS-Windows would be different from that used by a computer running Linux?
No. The same BIOS would work for both operating systems. Many computer owners install two or three operating systems on
Which flag is set when the result of a signed arithmetic operation is either too large or too small to fit into the destination?
Overflow
What are the x86 processor's three basic modes of operation?
Real-address mode, Protected mode, and System Management mode
Describe SRAM and its most common use.
SRAM is an acronym for Static RAM, used in CPU cache memory
In protected mode, which register references the descriptor for the stack segment?
SS Register
List at least two features found in the Intel P965 Express chipset.
Select any two features from the following list: 1. Intel Fast Memory Access uses an updated Memory Controller Hub (MCH). 2. I/O Controller Hub (Intel ICH8/R/DH) that supports serial ATA devices (disk drives). 3. Support for 10 USB ports, 6 PCI express slots, networking, and Intel Quiet System technology. 4. High definition audio chip.
Which flag is set when an arithmetic or logical operation generates a negative result?
Sign
Which type of RAM is used for Level 2 cache memory
Static Ram
What is the purpose of the 8259A PIC controller?
The 8259 is the interrupt controller chip, sometimes called PIC, that schedules hardware interrupts and interrupts the CPU.
In the example regarding displaying a string of characters, which level exists between the operating system and the video controller card?
The BIOS level
Define multitasking
The CPU executes multiple tasks or programs by rapidly switching from one program to the next. This gives the impression that all programs are executing at the same time
Which Intel processor was the first member of the IA-32 family?
The Intel 80386.
After a program has been loaded into memory, how does it begin execution?
The OS executes a branch, like a GOTO to the first machine instruction in the program.
What is the function of the OS scheduler?
The OS scheduler determines how much time to allot to each task, and it switches between tasks
Which Intel processor first introduced superscalar execution?
The Pentium
Which Intel processor first used MMX technology?
The Pentium II
Of the four levels of input/output in a computer system, which is the most universal and portable.
The application program level
What advantages does a USB device offer over a standard serial or parallel device?
The computer can query a device connected via USB to find out its name and device type and the type of driver it supports. The computer can also suspend power to individual devices. None of these capabilities is possible with serial and parallel port
In real-address mode, demonstrate two segment-offset addresses that point to the same linear address
The following segment-offset addresses point to the same linear address: 0640:0100 and 0630:0200.
At which levels can an assembly lannguage program manipulate input/output?
The operating system, BIOS, and hardware levels.
When the processor switches from one task to another, what values in the first task's state must be preserved?
The program counter, the task's variables, and the CPU registers (including the status flags).
Describe the RISC design approach
The term RISC stands for reduced instruction set. Is a small set of simple (atomic) instructions that may be combined into more complex operations
What is the main advantage to using the paging feature of x86 processors?
The total size of all programs loaded into memory can exceed the amount of physical memory installed in the computer.
Can you think of a reason why MS-DOS was not designed to support protectedmode programming?
This is an open-ended question, of course. It is a fact that MS-DOS first had to run on the 8086/8088 processors, which only supported Real-address mode. When later processors came out that supported Protected mode, my guess is that Microsoft wanted MS-DOS to continue to run on the older processors. Otherwise, customers with older computers would refuse to upgrade to new versions of MS-DOS.
Describe VRAM.
VRAM (video ram) holds displayable video data. When CRT monitors are used, VRAM is dual ported, allowing one port to continuously refresh the display while another port writes data to the display.
The two ways of describing an address in real-address mode are segment-offset and __________
linear or absolute
