Computer Architecture : is 0 really 0 ?
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in computers' circuits is the bit 0 really represented by no currency or it is a small signal that the computer is made to treat as 0 ? thank a lot !
You can check the spec sheets for processors, generally these days they run on less than 5V, more like 3.3V or less. A range 0V through 1.5V will be treated as 0, and 1.5V to 3.3V will be treated as a 1. Docs like this [^] will help (table 3 - min high level, max low level)
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in computers' circuits is the bit 0 really represented by no currency or it is a small signal that the computer is made to treat as 0 ? thank a lot !
Both 0 and 1 in a chip are usually represented by a voltage rather than a current, because they're made out of FETs instead of BJTs. Anyway, a closed transistor doesn't reach infinite resistance, not even the silicon oxide around it has infinite resistance, so you'll always have some non-zero voltage (and current).
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-5v? I can't see how you can have tristate binary. What sort of logic was this?
Regards, Rob Philpott.
Rob Philpott wrote:
-5v? I can't see how you can have tristate binary. What sort of logic was this?
Quantum computers use tri-state binary.
Jeremy Falcon
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Certainly, at a software level. But I've yet to see any sort of bus that uses three logic levels.
Regards, Rob Philpott.
Rob Philpott wrote:
Certainly, at a software level. But I've yet to see any sort of bus that uses three logic levels.
Check out what a qubit is for quantum_computers[^]. It's the future of tech, at a really early stage though.
Jeremy Falcon
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the 205 from Kings Cross to Paddington via the Mall? [edit] to put correct bus number before I was corrected[/edit]
You cant outrun the world, but there is no harm in getting a head start Real stupidity beats artificial intelligence every time.
Bergholt Stuttley Johnson wrote:
[edit] to put correct bus number before I was corrected[/edit]
I try to avoid buses as they're always full of 'them', so have no ideas about numbers. That said, bearing in mind all you have to do is follow the Euston Road to make such a journey it surprises me that you take The Mall in on the way. Either way, I'm reasonably sure that they don't use -5v.
Regards, Rob Philpott.
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Rob Philpott wrote:
-5v? I can't see how you can have tristate binary. What sort of logic was this?
Quantum computers use tri-state binary.
Jeremy Falcon
Yeah, perhaps out of scope of the original question. Quantum computers do my head in. Witchcraft, I tell you!
Regards, Rob Philpott.
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-5v? I can't see how you can have tristate binary. What sort of logic was this?
Regards, Rob Philpott.
Chuck Norris has a three-state one-two punch.
You'll never get very far if all you do is follow instructions.
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-5v? I can't see how you can have tristate binary. What sort of logic was this?
Regards, Rob Philpott.
There is a problem with ternary logic. "Bit" is short for "binary digit". What would you shorten "ternary digit" to? The problem is equally terminological as technical! PS. In the UK, I am aware that a tit is a kind of bird.
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in computers' circuits is the bit 0 really represented by no currency or it is a small signal that the computer is made to treat as 0 ? thank a lot !
Usually the logical levels are represented by voltages, not currents. You may have either active-higth or active-low signals, see Logic Level at Wikipedia[^].
THESE PEOPLE REALLY BOTHER ME!! How can they know what you should do without knowing what you want done?!?! -- C++ FQA Lite
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Depends on the chip. Some read -5V as 0 and +5V as 1. Some are tri-state using -5V, 0, and +5V. It's actually voltage and not current that it is using. At least the chips I worked with years ago were that way. [Edit] And yes, some chips used 0V as 0 and +5 as 1. [/Edit]
There are only 10 types of people in the world, those who understand binary and those who don't.
That was some pretty good info. Thanks :-)
Regards, Nish
Check out 7 reasons C++ devs will love the VS 14 CTP by Nish Sivakumar Blog: voidnish.wordpress.com
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There is a problem with ternary logic. "Bit" is short for "binary digit". What would you shorten "ternary digit" to? The problem is equally terminological as technical! PS. In the UK, I am aware that a tit is a kind of bird.
Quote:
PS. In the UK, I am aware that a tit is a kind of bird.
Amongst other things yes. ;)
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Rob Philpott wrote:
-5v? I can't see how you can have tristate binary. What sort of logic was this?
Quantum computers use tri-state binary.
Jeremy Falcon
I thought it was just a complex superposition of 2 states, which ends up giving you 3 dimensions to work in so you can get things like 30 degrees away from true. :-D
Curvature of the Mind now with 3D
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Bergholt Stuttley Johnson wrote:
[edit] to put correct bus number before I was corrected[/edit]
I try to avoid buses as they're always full of 'them', so have no ideas about numbers. That said, bearing in mind all you have to do is follow the Euston Road to make such a journey it surprises me that you take The Mall in on the way. Either way, I'm reasonably sure that they don't use -5v.
Regards, Rob Philpott.
24v 64hp London Omnibus
You cant outrun the world, but there is no harm in getting a head start Real stupidity beats artificial intelligence every time.
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There is a problem with ternary logic. "Bit" is short for "binary digit". What would you shorten "ternary digit" to? The problem is equally terminological as technical! PS. In the UK, I am aware that a tit is a kind of bird.
Vivic wrote:
tit is a kind of bird
Nah, it's what birds have two of.
You'll never get very far if all you do is follow instructions.
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Usually the logical levels are represented by voltages, not currents. You may have either active-higth or active-low signals, see Logic Level at Wikipedia[^].
THESE PEOPLE REALLY BOTHER ME!! How can they know what you should do without knowing what you want done?!?! -- C++ FQA Lite
CPallini wrote:
voltages, not currents
Yes, but can you have one without the other?
You'll never get very far if all you do is follow instructions.
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CPallini wrote:
voltages, not currents
Yes, but can you have one without the other?
You'll never get very far if all you do is follow instructions.
Current Flows, Voltage is Pressure to use the water metaphor...
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Current Flows, Voltage is Pressure to use the water metaphor...
Yes, I know that, but it doesn't answer the question.
You'll never get very far if all you do is follow instructions.
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CPallini wrote:
voltages, not currents
Yes, but can you have one without the other?
You'll never get very far if all you do is follow instructions.
That is not the point. Logical levels are bound to voltages because electrical potential difference is the measured physical quantity. For instance a car battery providing 8A to the vehicle lamps would have no higher logical level than four CR2032 cells providing 20 mA to a red LED (and its series resistor).
THESE PEOPLE REALLY BOTHER ME!! How can they know what you should do without knowing what you want done?!?! -- C++ FQA Lite
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That is not the point. Logical levels are bound to voltages because electrical potential difference is the measured physical quantity. For instance a car battery providing 8A to the vehicle lamps would have no higher logical level than four CR2032 cells providing 20 mA to a red LED (and its series resistor).
THESE PEOPLE REALLY BOTHER ME!! How can they know what you should do without knowing what you want done?!?! -- C++ FQA Lite
I know that, but it doesn't answer the question.
You'll never get very far if all you do is follow instructions.
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Yes, I know that, but it doesn't answer the question.
You'll never get very far if all you do is follow instructions.
Well Voltage 'dropped' across a component, it appears one side, a different value on the other side giving a difference in voltage that can be read with a meter in parallel. Current is the 'thing' (for want of a better word) moving through the circuit to measure it you have to break the path and insert the meter (there are other methods like coils etc. but...). So you can measure a voltage across something with out the being current flow (such as wires before plugging in). Bad explanation but the best I can manage at this time-O-day have a look at howstuffworks.com I seem to remember they had a very basic explanation. I'm off home! :)