12. A. Explain resolution, with respect to a monitor. Signifies the number of dots (pixels) on the entire screen.

b. List two typical monitor resolutions. 800*600, 1024*768

c. Explain color depth, with respect to a monitor. The number of distinct colors that can be represented by a piece of hardware or software. Color depth is sometimes referred to as bit depth because it is directly related to the number of bits used for each pixel. A 24-bit video adapter, for example, has a color depth of 2 to the 24th power (about 16.7 million) colors. One would say that its color depth is 24 bits.

d. List two typical monitor color depths. 24bits, 32bits

e. Consider that the higher the resolution and the higher the color depth, the more system resources are required to display output on the monitor.

i. Use the resolutions from part b and the color depths from part d to calculate the amount of RAM required displaying the image.

1024*768, 32bits RAM = 1024*768*32/8 = 3145728 Bytes, about 3M

Explain the calculation you made in part in a way that confirms the statement made at the beginning of part "the higher the resolution and the higher the color depth, the more system resources are required to display output on the monitor." From the equation above we know, the capacity of RAM needed to display depends on resolutions and the color depths

13. Consider the following devices: speaker, mouse, monitor, printer, keyboard, modem, speaker, digital camera, ethernet jack

For the following questions, indicate which device(s) should be plugged in which port(s) A-H shown in the diagram below.

a. What device(s) can be plugged into port A? Mouse or keyboard

i. What is the name of this port? PS/2 ports

ii. Is this a serial port or parallel port? A serial port

b. What device(s) can be plugged into port B? Digital camera

i. What is the name of this port? USB

c. Is this a serial port or parallel port? PDA devices used to connect to DB-9 ports before the advent of USB ports. Other devices that can be connected to a DB-9 port are the external modem and the barcode scanner, in general, older electronic devices.

d. What device(s) can be plugged into port C? the external modem and the barcode scanner, in general, older electronic devices

i. What is the name of this port? serial port

ii. Is this a serial port or parallel port? serial

e. What device(s) can be plugged into port D? printer

i. What is the name of this port? parallel port

ii. Is this a serial port or parallel port? parallel port

f. What device(s) can be plugged into port E? Speaker

g. What device(s) can be plugged into port F? Monitor

h. What device(s) can be plugged into port G? Modem

i. What device(s) can be plugged into port H? Ethernet jack

14. a. Define RAM. (Random access memory) is a temporary holding area for both data and instructions. It is also referred to as main memory.

b. What is the unit of measurement typically used for the speed of RAM?

Latency measures the speed of RAM. Latency is typically measured in nanoseconds (ns), billionth of a second (10-9 sec).

c. What is SDRAM and how does it work?

SDRAM (Synchronous Dynamic RAM) used in many personal computers. It is fast and relatively inexpensive. It is synchronized to the clock so that data can be sent to the CPU at each tick of the clock, increasing the number of instructions the processor can execute within a given time.

d. Data on hard disk drives is accessed indirectly via the file system. How is data in RAM accessed? Data in RAM can be accessed directly via its address.What are the benefits of accessing RAM in this way?

RAM derives its name from the fact that its contents can be accessed in any order. This is in contrast to sequential memory devices, such as disks (hard, floppy and optical) and magnetic tapes, for which the data must be accessed to some extent in a fixed order. Thus, the times required for RAM to access any of its memory locations are virtually identical, in contrast to disks and tapes, which have delay times that vary according to the location on the media.

RAM features much higher access speeds than hard disks and optical disks. That is, it takes far less time to read data from and write data to RAM than it does for discs. This is due to the fact that access is entirely electronic, i.e., there are no moving parts to slow things down. RAM access time is expressed in nanoseconds, whereas hard disk access time is expressed in milliseconds.

e. With regard to RAM, what is volatility?

A characteristic of RAM is that it is volatile, in contrast to ROM (read-only memory), disks and tapes. This means that any data stored in RAM is retained only as long as the RAM chips are connected to a power supply. In the case of DRAM chips, moreover, not only must they be connected to a power supply but also they must be refreshed at frequent intervals by an electric current, hence the term dynamic in their name. The reason is that each bit of data is stored as a charge in a microscopic capacitor, and such charges quickly dissipate without refreshment. Thus, when the power supply is interrupted, the memory contents are lost. When a computer is turned on, the operating system and other files are once again loaded into RAM, usually from the hard disk.