Hello everybody.
Hаверное, это слегка офтопик, но не могу удержаться :)
Один thread c comp.arch.embedded
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От:Meindert Sprang ( snipped-for-privacy@NOcustomSPAMware.nl) Тема:Bit width?
Reading about buses, processors and memories being n bits wide makes me wonder: how wide is one bit?
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От:Grant Edwards ( snipped-for-privacy@visi.com) Тема:Re: Bit width?
One bit is one bit wide.
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От:Mel Wilson ( snipped-for-privacy@the-wire.com) Тема:Re: Bit width?
That's pretty much it. If you need expansion, you have to rely on the height. You can get some code efficiency with your semaphores if you store the P/V status in the upper half of the bit, and a tasks-waiting flag in the lower half.
Atmel ATmega processors support this really well with the BRHS and BRHC instructions: Branch If Half Carry Flag Set and ..Clear.
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От:Jim Granville ( snipped-for-privacy@designtools.co.nz) Тема:Re: Bit width?
Where have you been ? - have you not seen that newest flash stores FOUR levels per programming FLASH bit ? ((Intel et al )
That means we should start talk > Atmel ATmega processors support this really well with the > BRHS and BRHC instructions: Branch If Half Carry Flag Set > and ..Clear.
But what if you need to test the OTHER half of the carry flag, clearly, they forgot the orthogonal opcodes :
BROHS : Branch If Other-Half Carry Flag Set BROHC : Branch If Other-Half Carry Flag Clear
Longer term research shows it has not stopped here :
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От:Grant Edwards ( snipped-for-privacy@visi.com) Тема:Re: Bit width?
Often shortened to "quits".
The confusing thing is that a monetary bit is a half of a quarter, where a computer bit is four quarters.
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От:Ulf Samuelsson ( snipped-for-privacy@atmel.nospam.com) Тема:Re: Bit width?
Not completely true, with ARM processors having shadow registers for the PSR, you have to wonder about the depth of a bit as well. Pushing/popping PSR registers on the stack, forces you to introduce time, the fourth dimension.
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От:Jim Stewart ( snipped-for-privacy@jkmicro.com) Тема:Re: Bit width?
Troll season doesn't open for another month (:
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От:Casey ( snipped-for-privacy@cox.net) Тема:Re: Bit width?
It's equal to the width of 1,000,000 microbits.
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От:Paul Keinanen ( snipped-for-privacy@sci.fi) Тема:Re: Bit width?
Regarding the troll season, is it 1,000,000 microbits, 1,000,000 microibits,
1000 mbits, 1024 mbits, 1,024,000 microbits or 1,048,576 microbits wide :-).--------------------------------------------------
От:Vadim Borshchev (vadim.borshchev@127.0.0.1) Тема:Re: Bit width?
Imperial or metric ?
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От:Matthias Wei?er ( snipped-for-privacy@matwei.de) Тема:Re: Bit width?
Maybe you are searching for
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От:Greg Neff ( snipped-for-privacy@microsym.com) Тема:Re: Bit width?
Apparently, a 1 bit is 0.2280". I can't seem to find a 0 bit in my table of Numbered, Fractional, and Lettered Twist Drill Bit Sizes...
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От:Rick Merrill ( snipped-for-privacy@comTHROW.net) Тема:Re: Bit width?
A Quantum bit (called a Qbit) has three states, so it is 1.5 bits "wide".
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От:Jim Stewart ( snipped-for-privacy@jkmicro.com) Тема:Re: Bit width?
No one has yet addressed the size of virtual bits, imaginary bits and shadow bits.
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От:Jack Klein ( snipped-for-privacy@spamcop.net) Тема:Re: Bit width?
The width of shadow bits varies with the time of day. At dawn or sunset they are quite wide. Around noon, on the other hand, they are very, very narrow. There is a slight additional variation with latitude and season, but that is usually taken care of by a 1-bit FIR filter.
The formula for the width of imaginary bits is quite simple. It is the width of an ordinary bit multiplied by the square root of -1.
Virtual bits, however, have virtually no width at all.
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От:Ben Bradley (ben_nospam snipped-for-privacy@mindspring.com) Тема:Re: Bit width?
I learned when I was a computer center janitor that a bit is narrower than a bit bucket. We had to recycle bits because the local city would levy huge fines if they found any bits in the sewage.
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Roman