“LESSON-7 THE EMBEDDED COMPUTING PLATFORM”
Name: Jhon Paul A. Gervacio
Date: November 29, 2021
Section: IV-BSCpE
Score:
ACTIVITY :
I. Directions: Read and analyze the given questions below. Write your answer on a separate
sheet.
1. Differentiate bus from a wire. Provide a specific example.
A bus is used to carry large amounts of current. It is from a collection of wires with
protocol. The amount of currents that a bus can provide is not suitable in wire. It only has very
short length compared to wire. A specific example of bus is the ARM Advanced Microcontroller
Bus Architecture or known as the AMBA. It is used to communicate and pass messages between
different components on a chip. While, the specific example of wire is a single conductor wire on
which mostly used wire inside a home.
2. What are the different I/O techniques? Explain each.
The different I/O techniques are the programmed I/O, interrupt-driven I/O, and direct
memory access(DMA).
Programmed I/O was the most simple type of I/O technique for the exchanges of data or any
types of communication between the CPU and I/O devices.The CPU executes a program that gives
it direct control of the I/O operation. When the CPU issues a command to the I/O module, it must
wait until the I/O operation is complete. If the processor is faster than the I/O module, this is
wasteful of processor time.
Interrupt I/O is a way of controlling I/O operation whereby a peripheral that needs to make or
receive a data transfer sends a signal. This will cause a program interrupt to be set. However, CPU
can continues to execute other instructions before I/O operation has completed.
Direct Memory Access is a technique for transferring data within main memory and I/O device
without passing it through the CPU. This is not a time consuming process when issuing command
for data transfer and it is more efficien when large volume of data has to be transferred.
3. In computer terminology, how would you define a master from a slave?
A master actually refers to the ability of a part of computer system to control the working
of rest of the system. The slave suggests the characteristic feature of a part of computer system to
be dependent on other part to carry out the function that it is meant to perform. In particular, in a
computer system there is a device acts as the controller, whereas the other devices are the ones
being controlled.
4. What are the two categories of RAM?
The Static RAM and Dynamic RAM are the two categories of RAMs. Static RAM is
memory that does not need to be refreshed frequently. It is more expensive and faster than
DRAM as it also consumes a lot of power. By each clock cycle, it can accept one command and
send one word of data. The DRAM or the Dynamic Random Access Memory, is a type of
computer memory that requires regular refreshing. It is mostly used for main memory and is both
less expensive and slower than SRAM
5. In your own words, define RAM and ROM. Provide a specific example.
RAM is known as the random access memory sometimes known as main memory or
system memory. This is a volatile memory which means of a temporary storage, data will be
lossing once computer once turned off. It is responsible for initiating and speeding up your
computer, as well as resolving hanging issues. While, the ROM is known as the read-only-memory
which allows us to read data but cannot to change it. In contrast with the RAM, it is a non-volatile
memory, which means of a permanent storage, data won't be losing even the computer has turned
off. The RAM and ROM are among of the important parts of the motherboard. A specific example
of RAM is static RAM, a volatile memory on which you can maintain the data as when supply is
available. While the specific example of ROM is the hard drive, a non-volatile memory which
you can store the data and any software applications.
6. Research on how a touchscreen works and functions.
A different kinds of touchscreen work in different ways. There are called a resistive
touchscreens that when you press on the screen, you force the polyester to touch the glass and
complete a circuit—just like pressing the key on a keyboard. A chip inside the screen figures out
the coordinates of the place you touched. There are called a capacitive touchscreens that when
you bring your finger up to the screen, you alter the electrical field by a certain amount that varies
according to where your hand is. Capacitive screens can be touched in more than one place at once.
Unlike most other types of touchscreen, they don't work if you touch them with a plastic stylus.
There are called light pens on which contained a photoelectric cell that detected the electron beam
as it passed by, sending a signal to the computer down a cable. Since the computer knew exactly
where the electron beam was at any moment, it could figure out where the pen was pointing. Light
pens could be used either to select menu items or text from the screen (similar to a mouse) or, as
shown in the picture here, to draw computer graphics. There are called infrared on which just like
the magic eye beams in an intruder alarm, an infrared touchscreen uses a grid pattern of LEDs and
light-detector photocells arranged on opposite sides of the screen. The LEDs shine infrared light
in front of the screen—a bit like an invisible spider's web. If you touch the screen at a certain point,
you interrupt two or more beams. A microchip inside the screen can calculate where you touched
by seeing which beams you interrupted.
In particular, the touchscreen is a computer display screen that serves as an input device.
Its functions are to enable direct tactile and visual interaction between a user and their electronic
device. When a touch screen is touched by a finger or stylus, it registers the event and sends it to
a controller for processing. A touch screen may contain pictures or words that the user can touch
to interact with the device.
Reference:
www.techopedia.com/definition/3055/touch-screen
https://www.reference.com/world-view/function-touch-screen-5962328f88c7216b
https://www.explainthatstuff.com/touchscreens.html
https://www.iqboard.net/tag_touchscreen.php?id=555
7. What are the anode and cathode represents of a LED?
The anode represents of the positive lead of the LED. It is the point at which positive
current should enter the device from the more positive supply terminal, to make it light. The
cathode represents of negative lead of the LED. It is the point at which negative current should
enter the device from where electricity is given out or flows out of. The anode should connect in
the power while cathode should connect on the ground.
8. Explain the process of a four-cycle handshake
The four-cycle handshake is the simplest bus protocol. The process of four-cyclehandshake starts of the device 1 raises or signal the enq for the device 2 will be ready for accepting
the data. Second, the device 2 would responds or send signals with the ack when it is fully ready.
Now, the devices 1 and 2 can already transmit or receive data. On the third process the device 1
lowers enq once it has finished, signaling that it has received the data. On the four process the
device 2 lowers ack.
II. Given are the acronyms and abbreviations. Write what they stand for and provide a short
explanation.
1. enq - Enquiry
This is one of the pair wires dedicated to the handshake. On the four-hand-cycle, this is
where the device 1 send a signal after raising its output.
2. ack - Acknowledgment
This is one of the pair wires dedicated to the handshake. On the four-hand-cycle, this is
where the device 2 send a signal after raising its output or when it is fully ready of receiving data.
3. DMA - Direct Memory Access
It is among of the I/O techniques, a technique for moving data between main memory
and an I/O device that does not require the data to be passed through the CPU. In particular, when
it comes to direct memory access, the CPU is not involved in the I/O transfer. There are several
distinct types of buses, and this is one of them. It is used to communicate and send messages
between different components on a chip.
5. BIU - Bus Interface Unit
When a signal arrives to the processor, the bus interface unit is responsible for responding
to that signal. The BIU also responsible for creating all signals that are sent from the CPU to the
other components of the system.
Prepared by: Engr. Kent Jude Cuya