First, please see this page’s sub-menu items that importantly include the Numbering Systems presentation and tutorial (as introduced in LM 1, use a mouse roll-over on the 02 Architecture & Hardware menu item). As we move forward please keep Moore’s Law in mind and note the Lecture Capture for textbook material is located further down the page.
Computer Architecture describes a computer system by specifying its parts and their relations.
Von Neumann Architecture
Here is nice quick YouTube presentation introducing the Von Neumann Architecture to give a top level over-arching perspective. In the sub-menu you need to watch my Fetch-Execute Cycle Simulation demo for a more precise discrete view.
First, it is necessary to understand the Memory Hierarchy that categorizes memory/storage according to their access time, complexity and expense: http://en.wikipedia.org/wiki/Memory_hierarchy
Nice graphic from Alan Clements’ Architecture & Organization text.
In the Lecture Capture I compare the computer’s CPU measured in GHz and the hardrive operations which are measured in milliseconds. It is difficult to comprehend this disparity so while we are comparing milliseconds to nanoseconds, consider that a nanosecond is to one second as one second is to 11.5 days.
The Byte is the smallest addressable unit of memory and as such, every Byte has both (1) contents (instructions or data) which may or may not be meaningful (it may just be non-meaningful garbage until memory is initialized by the OS/Application) and (2) an address (machine address) whose size is in accord with the machine architecture (32 bit, 64 bit).
The CPU can only execute instructions and operate on data that are in ROM or RAM. As a result information must be brought in from storage (e.g. hard drive, DVD, flash drive, network, etc.) to be executed and therefore storage often requires and suffers from mechanical latencies several orders of magnitude slower than the CPU (see memory hierarchy above). This is why increasing the amount of available RAM increases your computer’s efficiency (i.e. it doesn’t have to wait for data from storage (in accord with in the memory hierarchy above).
We have an entire LM on Storage in the coming weeks.
Textbook Chapter 2 Presentation
Again, please note I will not do this for every video and topic but topics covered in recording not in the text:
In a nutshell, data requires lossless compression whereas lossy compression is appropriate for media where human perception is involved. This is critical knowledge for Web Designers and Marketing as we should not use up a user’s data plan forcing them to download large media files and mobile browsing is now the norm.
Understanding this is necessary and also provides the answer to my question in class “why is a boot sector virus so pernicious”.
Also, please look up and understand the difference between the terms: Homogenous & Heterogeneous reminding you that you are now responsible for looking up any terms you are unfamiliar with.
I recommend you keep track of the Raspberry Pi and Arduino platforms as I believe these will increasingly be used in embedded/robotics Rapid Application Development (RAD) and innovation. On a more immediate personal level you will find one student’s CISS 100 Final Project in the Final Projects section of this Website where they created a home media server using a Raspberry Pi.
Green Mobile Architecture Approach
Please see sub-menu for PhoneBloks/Google Ara. This has finally launched to some extent (Motorola has launched a lesser version).
Additional Architecture & Hardware Resources