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1

You gave us one analogy now I will give you another one. What if you were greeting people at the door of an establishment and collecting coat and hat from each person who entered to visit. If you knew for sure that the last person to visit would be the first to leave, you could store the hats and coats in a stack like structure. Then as each person left, you ...


7

Short History I'm old enough to have worked on computers that didn't possess hardware stack support. (You can always manufacture your own stacks in software, obviously, if you have the necessary instructions for some kind of indirect memory references, anyway.) The HP 21xx series processor family is a good example. "Back in the day" it was commonly ...


2

why this concept exist at all The stack is a very simple temporary storage mechanism. To extend your analogy, it's the entry table of your room (that you pull out of the wall). It's already there, you know where it is and how to reference it. So you stack your item(s) there. When you are done, you take your stuff and put the table away, giving you your ...


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But if stack pointer puts x on the top y. How will it reach y without removing x then? So to me stack must make things(data access) even harder. It doesn't have to. These variables are temporarily stored on the stack in the exact order (push), then they are retrieved back in the reverse order. At each function call, interrupt,... the processor pushes the ...


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The current place of execution is stored into stack when starting a subroutine, so that when the subroutine ends, it can be popped off the stack. This enables a way to store context what the program was doing before changing context to another subroutine, and even makes it possible for subroutine to call itself recursively, so it goes only one level up on ...


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Very old question, I know, but it seems that none of the answers here mention TOSLINK, a well-established (standardized in 1983, apparently) system for data transmission using visible-light LEDs and photosensors. Its original specification gave it a limit of 3.1 Mbit/s, but modern implementations manage over 100 Mbit/s. It uses a red LED emitter into a ...


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It's only true if your consider OOK modulation. In OOK, a signal emission corresponds to a 1 and no signal to a 0. However it's not widely used because of hardware complications. With BPSK modulation, a 0 is send as a -1. It makes hardware design easier as you always have the same energy level to manage. => For the emission, you can make your amplifier ...


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Other people have pointed out that in most cases the energy used to transmit a zero is the same as the energy used to transmit a one. However, if that is not the case, then you are correct that it is more energy-efficient to transmit more of one or the other. If the probability of a 1 symbol is p and the probability of a 0 symbol is 1 − p, then the average ...


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I only know one case. Here transmitting more ones saves power. GDDR4 and DDR4 memories have a feature called Data Bus Inversion. The data lines are pulled up with resistors (terminated to high) and driven low with MOSFET switches. In this case driving low takes more power. So if the byte to be transmitted has many zeros, the driver will invert all bits in ...


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TL;DR: no, there's no such scheme that we wouldn't already be using. There's reasons, below. Information theory tells us that we have to transmit the least bits (using less energy than transmitting more bits) if we use source coding to compress the input data – making 0 and 1 equally likely. The job of channel coding is to then take these equally likely bits ...


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It depends completely on what interface and encoding is used for data, if there is any difference of transmitting ones or zeroes, so there is no general answer. For your extremely complex case of Ethernet, it depends on which Ethernet you mean. For example, 10Mbps Ethernet uses Manchester encoding, so there is no difference if you send a frame full of ones ...


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could power consumption be lessened by inverting Ethernet frames to optimise for more "ones" or "zeros" Pretty much the majority of long-haul data transmissions are synchronous. These consume the majority of the total power. Synchronous means that clock and data are embedded. In turn, this means that on average, the high bit-count equals ...


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