Looking for advanced knowledge on computer circuitry

[macwoni]

Hello,

 

I've been interested in computer science for quite some time now but have found it relatively difficult to find the answers I'm looking for without asking somebody with a phd.I keep wondering what happens to a computer when you click on a file.I already know the basic answer "oh yeah it reads from the harddrive that's where the file is stored".But I need to know more details than that.I'm looking for the nitty gritty.How did humans manage to be able to tell a computer what to do when I click on a program? I know electricity shoots down into the computer in a million different places but I'm missing the "inbetween".How does it interact with whatever you're doing on the screen? I know about pixels.But how is the data from those pixels transferred into the computer so that the cpu can understand it? yeah,i know through electricity.But HOW exactly?.If anybody can point me into the direction I need to go to start learning you'll be on my friends list for life.I've been looking for the answer to this question for quite some time now.

[Pangloss]

We have a lot of folks here who can answer questions. Post some questions and we'll take a shot at it. You'll need to be a little more specific than "how exactly". Post what's confusing you and we'll take a shot at it.

 

With regard to your specific question about pixels, the computer is programmed to understand the existence of a grid of specific dimensions, and each position on that grid is given a coordinate. The position can have two coordinate values and a color value, all three of which are stored in computer memory.

[BhavinB]

Don't really have too much time to explain this at the moment...maybe someone else will give a more detailed answer.

 

Anyways...if you can describe a logical process of events based on inputs and outputs, then it can most likely be modeled using Finite State Machine models. Almost all finite state models can be converted into a logical circuit based on logic gates...these are mathematic representations (ex AND, OR, NOT etc...).

 

http://en.wikipedia.org/wiki/Finite_state_machine

 

These logic gates can then be built using transistors which are basically just switches...its a bit complicated to understand how transistors can come together to form logic gates, but just believe me for now that they do.

 

So basically, this sums up alot of digital electronics. A concept based on inputs and outputs gets modeled at a high level, then converted to logical circuitry and then to physical transistors which we can build. Current day computers are an evolution of this concept.

[macwoni]

Ok I guess my drawn out question confused a lot of people.So what I want to know in a nutshell is how the information from the monitor is transferred into electricity so that the cpu can use it.

[Klaynos]

Ok I guess my drawn out question confused a lot of people.So what I want to know in a nutshell is how the information from the monitor is transferred into electricity so that the cpu can use it.

 

It's not, the VDU is an output device

 

But when you type on a keyboard, every key press sends a code to the computer in binary, this code is then interoperated as a character using the logic that BhavinB talks about and the computer does with it what is required.

[YT2095]

it`s not at all hard to understand but you DO need some basics 1`st.

 

think of Pigeon holes in a post office sorting area, each hole has an Address (like a grid reference) in this pigeon hole the mail man may put in letters like Gas bill or electric bill etc... this is called Data.

 

the monitor screen has the same format, each pixel location has data as to what color it should be.

 

the Keyboard IS the Addresses and each letter you type is Data.

 

the HDD has masses of Data on it, in the Directory (like a phone book) it has the addresses of this data, in this case it`s not and electric bill or gas bill it`s your File.

 

RAM is just purely the Pigeon holes all empty adresses, and capable of holding data in each address, this is usualy in way of a Program.

 

the Stack pointer in a computer reads each address and does what the data in each place tells it, if it tells it nothing it moves onto the next address in the sequence.

 

most of the data if for the CPU to act on, so the stack pointer just counts through each address in turn giving the CPU instructions.

 

this is Very hard to explain the whole thing in text over here, but I suggest you learn the basics 1`st.

 

the rest is just easy then

[JohnF]

When you press a key on a keyboard you are, for the duration of the key press, creating one or more electrical paths that are detected by an electronic component. This component stores a number in it's memory that represents the electrical pattern it has detected because of the key being pressed. When you release the key the stored number is sent along the keyboard cable as a series of electrical pulses.

 

When an electrical signal is detected on the keyboard cable by the CPU it causes the CPU to monitor the incoming signal. This signal is interpreted by the CPU as a number, a number that represents the letter on the key you pressed. The CPU stores this number in memory and also changes the memory used to store the screen display so as to display on the screen, in an appropriate place, the graphical representation of the key that you pressed.

 

So as you can see, pressing the key causes the computer to store the key press and also indicate to you what key was pressed. At this level the computer is not 'looking' at what is on the screen. The screen is there to let you know what the computer is doing. When a computer does 'look' at what is on the screen it is to read the screen memory and use whatever it had stored there before. Each pixel on the monitor is a representation of one or more bits in the screen memory on the graphics card or within the computers memory.

 

This process continues until you press a particular key, perhaps the return/enter key, that causes a new response from the computer. Think of it as someone asking you a question. You remember each word until you have a complete sentence that forms a question. A change in pitch of the others persons voice is the key to you knowing when the complete question has been asked. Unlike the computer though you don't repeat each word the other person says to you.

 

Once you press the return/enter key on the keyboard the computer then reads all the characters it has stored from your key presses. At this point it could be some software like an interpreter that is being run to process the key strokes. By reading each key value in turn the software will determine what instruction you have given. If the instruction is valid, of the correct syntax, the computer will then attempt to execute the instruction. It may be that to execute the instruction the computer will adjust the display memory in such a way so that you will see the result of the instruction being executed on your monitor.

[macwoni]

Well does anybody have any good book references as to where I can read up more on the technical specifications? I've been studying the gates and they seem pretty straightforward but I'd like to go a little more in detail about the engineering itself.Any links to some good reads would be much appreciated.

[Genecks]

I suppose learning the etiology would be the most basic. You've got the power. It talks to certain devices. It goes to the CPU, BIOS, video card, and RAM. You just need to learn more about each component. The motherboard and the buses help communicate stuff. If I remember correctly, the BIOS sets the permissions for the various storage devices. After the BIOS is done, the devices are loaded. Afterwards, the devices tend to work on whatever mechanics/physics they have, such as magnets or various optical technologies.

 

Get a general idea of what's inside the computer. Research each part. Now, learn why each part works. Start going downward into a more specified learning path: Why does do that; now why does that of that do that; why does that of that of that do that? It's all about why. It's reductionism.

 

You could read about the ENIAC and go upward: http://en.wikipedia.org/wiki/ENIAC

 

http://en.wikipedia.org/wiki/History_of_computer_science

 

http://en.wikipedia.org/wiki/History_of_computing_hardware_%281960s-present%29'>http://en.wikipedia.org/wiki/History_of_computing_hardware_%281960s-present%29

http://en.wikipedia.org/wiki/History_of_computing_hardware

 

Electric impulses are interpreted by various components of the computer. No pulse is similar to a 0. A pulse is similar to a 1. The pulses travel on the motherboard / intergrated circuitry. These pulses travel to various components which then interpret the pulses and covert them to binary. The binary then is translated/interpreted eventually into commands, which can communicate to other devices.

 

To say the least, it's not only 1s and 0s, but it's also physics, electronics, chemistry, and how electricity works.

Oh, and math and logic.

[foodchain]

Well does anybody have any good book references as to where I can read up more on the technical specifications? I've been studying the gates and they seem pretty straightforward but I'd like to go a little more in detail about the engineering itself.Any links to some good reads would be much appreciated.

 

Eventually you will be facing chemistry and physics if you keep reducing, so there might be a point you can logically gate the question to as to what level you have questions on.

 

A lot with the computer has to do with the discovery and or creation really of the semiconductor.

[insane_alien]

i would suggest that you look at older, simpler computing devices first. they operate on exactly the same principles but just use different switches and storage methods.