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4

On the basis you can't link duplication across SE board, I'll duplicate here: https://stackoverflow.com/questions/20298991/does-generally-risc-processors-have-lower-power-consumption-than-cisc-processors No, they don't. It was commonly believed in the past that RISC CPUs were more power friendly, mostly due to the large overhead of maintaining the large ...


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In RISC-V, there is the Machine Implementation ID register (mimpid) that provides a unique encoding of the source and version of the processor implementation. Source: The RISC-V Instruction Set Manual Volume II: Privileged Architecture Version 1.7


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The architecture defines what results software can expect when running on an implementation conforming to the architecture. It is essentially a contract that ensures binary compatibility between different implementations and microarchitectures. In general, the ISA only makes up a (small) portion of the architecture (x86, AMD64, ARM, RV etc). The architecture ...


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For x86, you can use the CPUID instruction. It allows you to query various pieces of information about the CPU. It's built right into the CPU (and is not an operating system service).


0

A wafer passed all 999 steps but failed on the 1000th step -- Ouch. It also take time and many steps to create a layer: photo-resist/developer/scanner/etch/clean/SEM and etc...That's why manufacturers try to increase the density rather than stacking. For example, building a single story house is different than building a 100 story skyscraper. You can't just ...


3

Another good option is to use branch prediction. There are many branch prediction algorithms which you can research. Many modern processors use branch prediction. So if the branch predicted is the right one, you win and save cycles. If the branch predicted is the wrong one, you have to clear the data. Out-of-order execution can be used to keep the CPU busy. ...


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RISC-V is not a CPU, it's an Instruction Set Architecture (ISA). ISA only specifies the instruction set and some registers. ISA does not specify where the Memory should be located, which is a matter of hardware implementation. The goal of ISAs is to enable binary compatibility between 2 processors that implement the same ISA, even if they use different ...


2

You asked for "the lowest level above transistors". And the lowest level you will use either a NAND gate or a NOR gate, depending on how you interpret voltages as truth values, and depending on your exact technology. However, that lowest level is not a "two input, one output NAND gate"; you'd throw away too much if you go straight to this ...


9

"In my CS program, my professor has claimed that NAND gates are the most basic gate to engineer, and so every other gate and higher-level circuits found in CPUs are made from NAND gates" A two input CMOS NAND gate uses four transistors. A CMOS NOT gate uses only two transistors. Therefore a NAND gate is definitely not the smallest CMOS gate in ...


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In my CS program, my professor has claimed that NAND gates are the most basic gate to engineer, and so every other gate and higher-level circuits found in CPUs are made from NAND gates “Yeah? Well, you know, that's just like, uh, your opinion, man.” - The Dude Your professor is … not correct, on several levels. Let's unpack this. NAND gates are the most ...


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On most processors today, the lowest level of programming is machine code. There were some processors in the past which actually ran their own programs which interpreted your programs, but that was rare and the company eventually went out of business. You may have heard of microcode. Some low-end CPUs did run actual interpreters written in microcode. On ...


2

A bit of simpler and more concise answer. 5G and other high frequency devices are implying the analog signal frequency they receive. However the way CPU/MCU communicate with those devices is digital. The data rate (not the wave frequency) carried over 5G is much lower and is something that those CPU and MCU can likely process. Then there is designated ...


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This question is too broad but I'm happy to give a few pointers. In our days, most electronic devices contains some sort of CPU, MCU or FPGA, because the cost have become so low that it doesn't make much sense anymore to implement logic in hardware. In some cases, like remote control, toys, specialized dirt-cheap chips may be used that implements the logic ...


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The comparison is apples-to-oranges since a digital circuit is dissimilar to an analog one as far as its requirements and limiting factors for speed. A limiting factor for digital speed is the propagation delay from storage element to storage element on the critical path - as a conceptual example, the output of a flipflop or similar, through a number of ...


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Let me try to summarize what you propose, because I'm not completely sure I follow your description. You have an ALU (for example) that can perform different computations. Alongside the ALU you have a block of logic that generates a "Done" signal that will go high when the computation is finished. The "Done" logic is designed so that the ...


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So, how do processors deal with the frequencies in the range of 20-100 GHz? They don't. Even if we consider a demodulation of data to lower frequencies from carrier frequencies, there needs to be a computing piece for doing that. No, there doesn't. There needs to be an analog piece for doing that. Note that our goal is to design a circuit which takes the ...


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Certainly current general-purpose processors run in the low GHz clock speeds. However, purpose-designed circuits are capable of running at higher speeds. The parts of the circuit that need to handle the carrier and encode/decode data are quite limited and typically exchange data via buffers, so the CPU itself can handle data at much lower speeds. ...


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