revision cos2621
1.1 An I/O device is referred to as a - (correct Answer) - peripheral
provide storage to the CPU - (correct Answer) - Registers
NASM is a(n) ___________ while DEBUG is a(n) _______. - (correct Answer) - assembler, utility to
assemble and debug programs
Consider the following assembly language program fragment:
org 0x100
label1: dw 0x76EF
nop
mov ax,ax
nop - (correct Answer) - 76h is stored in position 101h and EFh is stored in position 100h.
instructionThe processing required for a single instruction is called a(n) __________ cycle. - (correct
Answer) - instruction
The key advantage of the __________ design is the fact that it eliminates contention for the cache
between the instruction fetch/decode unit and the execution unit. - (correct Answer) - split cache
A logical cache stores data using __________. - (correct Answer) - virtual addresses
The sum of the seek time and the rotational delay equals the _________, which is the time it takes to get
the read/write head into position to read or write. - (correct Answer) - access time
Suppose a machine has seven (7) general-purpose 32-bit registers. How many bits must be reserved in
the machine code instruction in order to address any one of these seven registers? - (correct Answer) - 3
Which instruction would you use if you want to branch to label TEST if the carry flag is set? - (correct
Answer) - JC TEST
Which of the following are characteristics of Blu-ray DVDs:
a. They can store more than 20 GB per side.
b. They have slightly more storage density as normal DVDs.
c. They use a short wave-length 405 nm laser.
d. They use a red-blue laser.
e. There are two versions available: read-only (BD-ROM) and recordable many (BD-M). - (correct Answer)
, - a, b, c and d
1.12 The result of the following hexadecimal addition is_______.
ABh + 9Ch - (correct Answer) - 147h
1.13 What is the postfix version of the following infix expression?
(A * B + C)/ (E - F) - (correct Answer) - AB*C+EF-/
Suppose AX contains the value A2B4h. What will be the result of the following instruction?
sar ax,4 - (correct Answer) - AX
Give four reasons for writing programs (or program fragments) in assembly language rather than using a
high-level programming language? - (correct Answer) - 1. Code is often much faster.
2. Insight into the problem often allows real improvement in performance.
3. It allows complete access to hardware.
4. It can be used to write function libraries that are compatible with multiple operating systems.
Briefly describe two different approaches to dealing with interrupts. - (correct Answer) - (1) Disable all
interrupts √ while an interrupt is being processed.
(2) Define priorities for interrupts √ and to allow an interrupt of higher priority to cause a lower-priority
interrupt handler to be interrupted.√
List the advantages and disadvantages of memory mapped I/O. - (correct Answer) - Advantages
1. No additional control lines are needed √ on the bus to distinguish memory commands from I/O
commands.
2. Addressing is more flexible. √ Examples: The various addressing modes of the instruction set can be
used, and various registers can be used to exchange data with I/O modules.
Disadvantages
1. Memory-mapped I/O uses memory-reference instructions, which in most machines are longer than
I/O instructions. The length of the program therefore is longer. √
2. The hardware addressing logic to the I/O module is more complex, √ because the device address is
longer.
Briefly discuss flash memory erasing technology. - (correct Answer) - • electrical erasing technology
• An entire flash memory can be erased in one or a few seconds (in a flash)
1.1 An I/O device is referred to as a - (correct Answer) - peripheral
provide storage to the CPU - (correct Answer) - Registers
NASM is a(n) ___________ while DEBUG is a(n) _______. - (correct Answer) - assembler, utility to
assemble and debug programs
Consider the following assembly language program fragment:
org 0x100
label1: dw 0x76EF
nop
mov ax,ax
nop - (correct Answer) - 76h is stored in position 101h and EFh is stored in position 100h.
instructionThe processing required for a single instruction is called a(n) __________ cycle. - (correct
Answer) - instruction
The key advantage of the __________ design is the fact that it eliminates contention for the cache
between the instruction fetch/decode unit and the execution unit. - (correct Answer) - split cache
A logical cache stores data using __________. - (correct Answer) - virtual addresses
The sum of the seek time and the rotational delay equals the _________, which is the time it takes to get
the read/write head into position to read or write. - (correct Answer) - access time
Suppose a machine has seven (7) general-purpose 32-bit registers. How many bits must be reserved in
the machine code instruction in order to address any one of these seven registers? - (correct Answer) - 3
Which instruction would you use if you want to branch to label TEST if the carry flag is set? - (correct
Answer) - JC TEST
Which of the following are characteristics of Blu-ray DVDs:
a. They can store more than 20 GB per side.
b. They have slightly more storage density as normal DVDs.
c. They use a short wave-length 405 nm laser.
d. They use a red-blue laser.
e. There are two versions available: read-only (BD-ROM) and recordable many (BD-M). - (correct Answer)
, - a, b, c and d
1.12 The result of the following hexadecimal addition is_______.
ABh + 9Ch - (correct Answer) - 147h
1.13 What is the postfix version of the following infix expression?
(A * B + C)/ (E - F) - (correct Answer) - AB*C+EF-/
Suppose AX contains the value A2B4h. What will be the result of the following instruction?
sar ax,4 - (correct Answer) - AX
Give four reasons for writing programs (or program fragments) in assembly language rather than using a
high-level programming language? - (correct Answer) - 1. Code is often much faster.
2. Insight into the problem often allows real improvement in performance.
3. It allows complete access to hardware.
4. It can be used to write function libraries that are compatible with multiple operating systems.
Briefly describe two different approaches to dealing with interrupts. - (correct Answer) - (1) Disable all
interrupts √ while an interrupt is being processed.
(2) Define priorities for interrupts √ and to allow an interrupt of higher priority to cause a lower-priority
interrupt handler to be interrupted.√
List the advantages and disadvantages of memory mapped I/O. - (correct Answer) - Advantages
1. No additional control lines are needed √ on the bus to distinguish memory commands from I/O
commands.
2. Addressing is more flexible. √ Examples: The various addressing modes of the instruction set can be
used, and various registers can be used to exchange data with I/O modules.
Disadvantages
1. Memory-mapped I/O uses memory-reference instructions, which in most machines are longer than
I/O instructions. The length of the program therefore is longer. √
2. The hardware addressing logic to the I/O module is more complex, √ because the device address is
longer.
Briefly discuss flash memory erasing technology. - (correct Answer) - • electrical erasing technology
• An entire flash memory can be erased in one or a few seconds (in a flash)
