Questions tagged [microprocessor]

The microprocessor is an integrated circuit that elaborates information in the form of digital signals. Not to be confused with a microcontroller, which embeds many additional devices to control embedded systems.

The microprocessor is an integrated circuit that elaborates information in the form of digital signals.

The discover of transistor made possible to build CPUs as integrated circuits, making possible the diffusion of computers. It allowed also an exponential grow in their computational power, in a fashion that has been described in 1970 by Gordon E. Moore:

The complexity for minimum component costs has increased at a rate of roughly a factor of two per year... Certainly over the short term this rate can be expected to continue, if not to increase. Over the longer term, the rate of increase is a bit more uncertain, although there is no reason to believe it will not remain nearly constant for at least 10 years.

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What's the difference between a microcontroller and a microprocessor?

What's the difference between a microcontroller and a microprocessor?
endolith
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Why are there no 256-bit or 512-bit microprocessors?

In an 8-bit microprocessor its data bus consists of 8 data lines. In a 16-bit microprocessor its data bus consists of 16 data lines and so on. Why is there neither a 256-bit microprocessor nor a 512-bit microprocessor? Why don't they simply increase…
Michael harris
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Can a CPU function with nothing more than a power supply and a ROM, using only the internal cache as RAM?

Can a CPU (such as the Intel i3/i5/i7/Xeon) with on-chip cache RAM use that as its only functional RAM, without any external memory banks attached? Or must there be external RAM, and the cache cannot be accessed or used alone? Modern desktop/server…
Dale Mahalko
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Why does more transistors = more processing power?

According to Wikipedia, processing power is strongly linked with Moore's law: http://en.wikipedia.org/wiki/Moore's_law The number of transistors that can be placed inexpensively on an integrated circuit has doubled approximately every two years. The…
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Why don't we make CPUs with 1000s of layers to make use of space in the third dimension?

I am wondering why don't we make processors such as CPUs with 1000s of stacked layers to make use of space in the third dimension now that we have three-dimensional transistors. To be clear I'm referencing making something of a rectangular-prism…
Ethan
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How can a CPU deliver more than one instruction per cycle?

Wikipedia's Instructions per second page says that an i7 3630QM deliver ~110,000 MIPS at a frequency of 3.2 GHz; it would be (110/3.2 instructions) / 4 core = ~8.6 instructions per cycle per core?! How can a single core deliver more than one…
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How were the first microprocessors programmed?

This has just dawned on me that if you're writing an operating system then what are you writing it on? I ask this as I am reading a microprocessor fundamentals book from 1980 and this question popped in to my head: How was the first microprocessor…
Dean
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Readable and educational implementations of a CPU in a HDL

Can you recommend a readable and educational implementation of a CPU in VHDL or Verilog? Preferably something well documented. P.S. I know I can look at opencores , but I'm specifically interested in stuff people have actually looked at and found…
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Why do Microcontrollers need a Clock

Why do instructions need to be processed at set time intervals (i.e. with the use of a clock)? Can't they be executed sequentially - immediately after the previous instruction has completed? An analogy for the necessity of clocks in microcontrollers…
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What happens when an embedded program finishes?

What happens in an embedded processor when execution reaches that final return statement Does everything just freeze as it is; power consumption etc, with one long eternal NOP in the sky? or are NOPs continuously executed, or will a processor shut…
Toby
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Why are relatively simpler devices such as microcontrollers so much slower than CPUs?

Given the same number of pipeline stages and the same manufacturing node (say, 65 nm) and the same voltage, simple devices should run faster than more complicated ones. Also, merging multiple pipeline stages into one should not slow down by a factor…
Michael
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What actually is a shadow register?

I noticed the term Shadow Register while going through a datasheet of a TMS320F28335 DSP. What does it actually mean? Does it have a physical location in the CPU as the general purpose registers have?
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What could cause a microcontroller to unexpectedly reset?

One particularly irritating variety of bug in a microprocessor-controlled system is for the microprocessor to unexpectedly reset. An important tool for debugging this kind of problem is a list of possible causes. What could cause a microcontroller…
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How do I build a computer with a Z80 microprocessor?

I've got the chip, so how would I add: a clock, RAM, hard drive (maybe EEPROM?), a screen (LCD graphical screen?), input method (keyboard, mouse) ?
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Soft core processors vs hard core processors

I am doing a study on FPGA interfacing with microprocessors such as ARM9. I found the concept of soft core processors and hard core processors in my study. May I know what is the comparison between these two types, the similarities and differences…
How Xing Quan
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