GCSE Computing

For this task, please see the document(s) I posted on SMH for Unit 4 of A451.

1. Pixels are the smallest individual element in an image.  Pixel is a combination of which two words?
2. The number of bits used to store information in each pixel will determine how many colours can be represented.  Howe many colours could be represented by the following bits per pixel (bbp)?
   1. 1
   2. 4
   3. 8
3. 1. Pixels hold information on the levels of which three colours?
   2. If 8 bits are used for each of these colour levels, how many bits are used to hold information for each pixel?
   3. Using your answer for (b), calculate how many different colours can be represented.
4. 1. What is the difference between the terms ‘dimensions’ and ‘resolution’ when applied to digital images?
   2. What is a suitable resolution for:
      1. Viewing an image on screen?
      2. Printing an image?

By 20/1, keep it up class..

1. Explain what is meant by the terms:
   1. Binary digit
   2. Byte
   3. Nibble (& add why a nibble is used in computing)
2. Split these bytes into nibbles & convert them into hex:
   1. 11010011
   2. 01100110
   3. 11110011
3. Put these units into ascending order: megabyte, bit, nibble, terabyte, byte, gigabyte, kilobyte
4. A computer contains data and instructions in binary.  Explain why computers use binary.
5. Bytes, kilobytes and megabytes are units for the amount of data stored in a computer.  State which of these units is most appropriate for the following items of data:
   1. A one-page document
   2. A ten-minute film clip
   3. A person’s surname
6. How much is two terabytes in gigabytes?
7. Convert the following integers into binary ones:
   1. 213
   2. 69
   3. 130
8. Convert the following binary numbers into integers:
   1. 11010101
   2. 00101011
   3. 11001001

By 14/1.

Dear nice people!

Here are ten recommended resources:

1. The Learners’ Drive, i.e. W:\# BEC\COMPUTING\1–GCSE CLASS–1
   1. I regularly place class resources here which support your understanding, and can be used for homework tasks, revision, etc.
2. OCR Computing for Gcse – A451 Computer Systems and Programming Revision Guide
   1. £9.29 on Amazon
3. OCR Computing for Gcse – Students’ Book
   1. £17.99 on Amazon
4. My Revision Notes OCR Computing for GCSE Computer Systems and Programming
   1. £7.99 on Amazon
5. GCSE Computing Theory: for the OCR Exam Board
   1. FREE on Kindle
6. Codecademy Python.
7. The folder (containing resources) I will hand out as soon as the folders I ordered arrive.
   1. Until then, your notes in your workbook.
8. http://cambridgegcsecomputing.org/
   1. So excellent.
9. OCR’s resources: http://www.ocr.org.uk/qualifications/gcse-computing-j275-from-2012/
   1. In particular, their past papers and marking schemes – amazing resource.
   2. Someone asked me last week, ‘Hey sir, should I also look at the past papers and marking schemes from OCR to see how to describe this knowledge in exam questions?’
   3. I replied, ‘Well, that’s what a good student would do…’
10. This blog.

Any comments on these resources?  Post them here, this is the place.

Nice people!

Fancy playing a game this half-term AND learning about coding & assembly language?

Then download and play the Human Resource Machine:

http://www.gog.com/game/human_resource_machine

It’s £6.49 on Gog.com, AND is also on Steam, if you happen to subscribe to that.

I strongly recommend this.  You can feel like you are gaming, but actually, these are the very skills you need to build for the LMC Controlled Assessment which is, after all, just around the corner.

Post to this thread any impressions of the game (if you play it).

You should!

Line by line, comment on this program – describe what each of these 15 lines do:

INP

STA first

INP

STA second

INP

STA third

LDA third

OUT

LDA second

OUT

LDA first

OUT

HLT

first DAT

second DAT

third DAT

BY FRIDAY 23/10.

Read all seven sections of this: http://www.bbc.co.uk/education/guides/zrxncdm/revision

1. How might you add some SELECTION to this algorithm: unlock the door, open the door, enter the room, switch on the light, close the door behind you.
2. What did you find useful in Andrew Robinson’s explanation of how IF, THEN and ELSE statements are used when programming in Python?
3. How can IF, THEN and ELSE make an algorithm more intelligent?
4. When a program uses selection, what does it base its choices on?  (Do not use the word ‘information’ in your answer.)
5. ‘The only way for a computer to discover the circumstances is to collect inputs and compare them to known values.’  Explain what this means using an example we have encountered in class.
6. Describe, with examples, the difference between IF-ELSE and IF-ELIF-ELSE.
7. Commentate in pseudo-Python on an everyday, non-computing transaction you have in terms of selection, using terms such as IF, ELSE, etc.  Here’s what I’m looking for: ‘print (‘Start lesson’) IF Ugnius is talking, print(‘SCHUSCH!’) ELSE print(‘I start talking’) IF Ugnius == doing too much banter OR Naweesha == chit-chatting to her pals OR Apy is wearing her party hat, print (‘Send to Naughty Chair’) ELSE: print(‘keep calm and carry on teaching’)
8. Take this test and tell me your score: http://www.bbc.co.uk/education/guides/zrxncdm/test – Also describe one question you got wrong (if you got any wrong) and what mistake you made.

BY NEXT TUESDAY and notice we have one more homework posted below too.

1. What is meant by an algorithm?
2. In a computer program what do you have to declare to hold any numbers you input?
3. These were given an initial or starting value. What is this called?
4. What is a string?
5. When input is converted to a number using ‘INT’, what type of number would be returned?
6. Describe an algorithm to make ONE of the following – ensure you get the sequence right and include at least one loop:
   1. A cup of coffee
   2. A cup of tea
   3. Lasagne
   4. Pizza
   5. A sandwich
7. Read this section: http://www.bbc.co.uk/education/guides/z22wwmn/revision 
   1. Describe how the ‘Bubble Sort’ algorithm works (it’s on the third slide).
   2. DO NOT COPY & PASTE!

Submit by Tuesday 20/10.

1. Explain what is meant by ‘machine code’.

2. Explain why other languages were developed to allow humans to program computers.

3. Why is ‘assembly language’ referred to as a ‘low level’ language?
4. What are mnemonics and how are they used in assembly language?
5. What is an ‘assembler’ used for?
6. What are ‘high level languages’?
7. List three examples of a high level language.
8. List three advantages of assembly language over a high level language.
9. List three advantages of using a high level language over assembly language.
10. Compilers and interpreters are needed to translate the high level code into machine code. What is the difference between a compiler and an interpreter? Give an advantage and disadvantage of each.

JUST ONE HOMEWORK THIS WEEK – IT’S GOOD TO BE YOU!

1. Describe an input device (for a computer) in terms of its functions and features. Cover what it does and how it works.
2. Same for output device.
3. A gardener is going to buy some new hardware. Identify 2 input devices and describe how he/she might use them when working with clients.
4. Describe a specialist input device (for a computer) in terms of its functions and features. Explain how it can assist users with 1 specific need.
5. Same for specialist output device.

1. Describe the difference between hardware & software.
2. Explain what is meant by the term input device.
3. Explain what is meant by the term output device.
4. Miley has purchased a new desktop home computer system. Name three peripherals she might expect to receive with the system.
5. Touchscreens can be described as both an input and output device. Explain how a touchscreen is an input device and an output device.
6. A shopping centre uses several remote-control CCTV cameras for security. An operator uses a computer to watch, control and record the output of the cameras. State an input, output and storage device which will be needed by the computer. For each (input, output, storage), explain the reason why it is needed.