All posts by Mr Stratton

Computing teacher and a PT at Coltness High School.
1. Computer Systems, Homework, Revision

Quick teaser

I lifed this from the 2011 paper it’s question 13

(b) The computer has a maximum addressable memory of 16 Gigabytes. Its address bus width is 32.
(i) Calculate the width of the data bus.
(ii) State why computers do not come with the maximum addressable memory installed.
(iii) State the effect that adding one new line to the address bus would have on the maximum addressable memory.

I thought it was a very good question. I will post the solution to it tomorrow, feel free to comment with your answer but I don’t want you to copy and paste it from the Marking Instructions above.

Computing Higher

Interfacing Revisited

We went back over interfaces today. After the class I had a look about for another set of powerpoints for you to use as revision. There are others out there, just search for them.

We also looked at wireless PAN devices today such as Bluetooth. Remember future development in peripherals, will still have all the issues of today. So the Interface will be required to connect devices to be machines. USB3.0 and Thunderbolt are two of the new standards that give transfer speeds of 5Gbps and 10Gbps. Some interfaces allow for daisy chaining so one port on a computer can have multiple devices connected to it without a hub (Firewire & Thunderbolt).

Revision

Int2 Revision Presentation

Thank you to M. Feldman for allowing me to host and use this presentation.

[kml_flashembed movie="http://www.coltnesshigh.n-lanark.sch.uk/departments/CS_BizEdComp/Computing/NQ/Int2/Int%202%20Computer%20Systems/pres/INTERMEDIATE%202%20COMPUTING.swf" width="640" height="480" allowfullscreen="true" /]

Computing Higher

Input and Output Devices

Today’s lesson covered Digital Still and Digital Video cameras as well as Laser and inkjet printers. Here are the Peripheral Revision Notes for this section. I have copied the sections below from them.

I promised you a look at a Paintball gun acting like a inkjet printer well here we go. Remember though that inkjet printers only do a line at a time though

[kml_flashembed movie="http://www.youtube.com/v/fKK933KK6Gg" width="425" height="344" allowfullscreen="true" fvars="fs=1" /]

Digital cameras

A digital camera is one of the fastest ways to use pictures in a computer. There is no overhead in developing film and no need to scan images from a printed copy. Pictures are ready to use right away. Because they can be taken and downloaded to your computer in digital form they are ready to use in presentations or even send in email messages. It is now possible to print at home and achieve photo quality results.
The digital camera looks much like a conventional camera – only there is no film! Digital image data is stored in a memory card inside the camera. Digital photographs are bit maps, made up of thousands or millions of pixels with values to represent image brightness and colour.

Printers

Besides the monitor, printers are probably the next most commonly used output devices. They can be broadly classified as character printers, matrix printers or page printers. Character printers and dot matrix printers are pretty much outdated and have been replaced by affordable and more capable ink jet and laser printers.

Task. Why not look up some of the words from the paragraphs above? Example what is a page printer?

1. Computer Systems, Computing Higher

Computer Systems – Peripherals (arrangements)

During booklet four we will be looking at the following.

  • Description of the use and advantages of buffers and spooling
  • Description of a suitable selection of hardware, including peripherals, to support typical tasks including
    • production of a multimedia catalogue
    • setting up a LAN in a school
    • development of a school website
  • Justification of the hardware selected in terms of appropriate characteristics including
    • resolution
    • capacity
    • speed
    • cost
    • compatibility
  • Description of the features, uses and advantages of solid state storage devices including flash cards
  • Description of the development trends in backing storage devices
  • Description of the following functions of an interface:
    • buffering
    • data format conversion (serial to parallel and analogue to digital)
    • voltage conversion
    • protocol conversion
    • handling of status signals
  • Distinction between parallel and serial interfaces
  • Description and explanation of the current trends towards increasing interface speeds and wireless communication between peripherals and CPU
Computing Higher

Peripherals

Well we are back with a bang.

On Tuesday we went over the 2010 paper we used for exam practice, 2011 Mock. Here is the 2011 Mock Marking Instructions. If you want to ask any question just put it in a comment.

We also started the new peripheral topic in Computer Systems and have covered Keyboards, Scanners & Sound Cards. Search the blog to look for previous articles on these devices, there is more than one. There are a number of non traditional keyboards out there. The net even has articles on how to build a 3D scanner, I would have to say though that milk scanner is a little bit messy. With sound cards we discussed the merits of digital Vs audio, we used scratch’s soundgraph project to look at sample rates.

2. Software Development, Computing Higher

Welcome Back

1 Comment

I hope you had a restful and pleasant holiday. I decided not to post over the holidays to let you look through the articles on the site.

Anyway now is the time of new year resolutions and I saw these sites and though that it would be a great thing for some people who want to take programming forward or just learn a little more.

Codeyear is a weekly programming tutorial. Notice that I used I word programming and not software development. This is for people who want to learn to code and is less concerned with the waterfall method.

Codeyear was set up by Code Academy, this is a great way to learn how to program. It’s all about the code, there are no distracting videos just a box you type your code into. The language is Java script so you can use your new skills right away creating interactive web sites.