A CPU, or Central Processing Unit, is the heart of any digital computer.

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What components or circuitry exist that can provide extremely high speed, accurate clocks?

I've been curious for awhile now about doing some high speed projects, such as measuring time differences of radio wave reception, and was wondering if there exists components that provide clocks much ...
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1answer
64 views

CPU Core frequency [on hold]

I was going through the selection criteria of CPU (MCU/MPU/FPGA) and observed that core frequency is one important parameter while selecting a CPU. But I was unable to get information regarding, how ...
2
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2answers
134 views

How does a signal to the CPU look [closed]

I studied electronics in a far away past and have sadly forgotten quite a lot. I was wondering what a signal to an 8 bit CPU looked like. Suppose I want to send one word to the CPU, do I send 8 ...
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1answer
34 views

Difference between multiple pipelines and superscalar?

I have read some threads and the wiki articles, but still don't seem to understand what exactly the difference is between having multiple parallel pipelines and the superscalar architecture. I know ...
2
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1answer
64 views

How does the CPU handle XCHG internally?

While designing my own 16-bit CPU I wonder how the register-register XCHG instruction is executed internally. From computer science I know the DLX which doesn't provide XCHG and therefore doesn't need ...
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6answers
2k views

How to efficiently design the opcode for a CPU?

I am building a simple 16-bit CPU in Logisim and have the ALU ready and the opcodes that I want to have. Now I find it really hard to find the right coding for the commands so that the different ...
2
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2answers
106 views

How to compute CPU power consumption

I am working on a problem for which I need to know how much power will be consumed on a given CPU as the parameter sizes are increased. The following properties/attributes of the CPU are available: ...
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1answer
122 views

Are there any embedded Intel CPUs that can be soldered?

As known most of modern Intel CPU has contact pads instead of contact legs (pin). This makes it impossible to solder them onto the motherboard. But are there any Intel CPUs which have contact legs ...
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1answer
54 views

Do OSH projects exist for all SoC parts? [closed]

My understanding of the main parts of an SoC are: Microcontroller RAM (volatile memory) Flash/solid state RAM (permanent memory) Clock/Oscillator Ethernet NIC Power Management Bus (to connect ...
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4answers
413 views

What happens when microcontrollers run out of RAM?

It may just be a coincidence but I've noticed the microcontrollers I've used rebooted when they ran out of RAM (Atmega 328 if hardware specific). Is that what microcontrollers do when they run out of ...
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1answer
42 views

how can i using CPU8085 and PIO8155 crate an alarm circuit and program [closed]

example ; we have smoke sensor, speaker and my circuit.When Sensor has been active, speaker to sing it. i'm newbie in this topic. how can i do it like this circuit ?
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2answers
89 views

Why does the CPU consume more battery during computationally expensive operations?

Is it because the CPU increases its hertz as necessary? And when a CPU cycle has to enter a register, does the extra distance in its path measurably affect the speed of that specific cycle? And will ...
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3answers
170 views

What happens to the electricity after it is used in a CPU cycle? [closed]

After the pulse of electricity is used to complete a cycle through the CPU, what happens to it? Is it reused in anyway? Or does it goes straight to the ground wire? If it is not reused, why not?
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3answers
68 views

Finding Instruction Count

Computer A has an overall CPI of 1.3 and can be run at a clock rate of 600MHz. Computer B has a CPI of 2.5 and can be run at a clock rate of 750 Mhz. We have a particular program we wish to run. When ...
0
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1answer
66 views

CPU Execution Time / Performance

I'm trying to solve a question concerning performance. I have the final answer (24 * 10^9)but I can't determine how to get there. I know the formula for performance is Execution time: CPI * I * ...
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3answers
168 views

How to make the hottest CPU temperature?

Besides just running an infinite loop, are there any tricks (like maybe cache misses?) to making a CPU as hot as possible? This could be architecture specific or not.
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0answers
78 views

Why are there so many SMD resistors near CPUs and GPUs? [duplicate]

I'm not really sure if these SMDs are resistors or capacitors, but I've always wondered the purpose of them. Supposing that they are resistors: Do they work as a sort of protection measure? Current ...
0
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1answer
90 views

How to calculate cache size?

A cache with a line size of L 32-bit words, S number of sets, W ways, and addresses are made up of A bits. Assume that the cache is word addressed, i.e., the low two bits of the address are ...
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1answer
117 views

How do you store A or B in a RAM of a CPU datapath?

I have an assignment to make a CPU, but am confused with how f_left and f_right are going to be used. I think they are to store ...
0
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4answers
156 views

How does a CPU choose a path? [closed]

This is the most baffling question of all other concepts. I ask my teacher "How does the computer choose a path?" "They program it" "How do they program it?" "..." I have a basic understanding ...
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0answers
73 views

Pipeline Processor Calculation

My assignment deals with calculations of pipelined CPU and single cycle CPU clock rates. The following data is given, about the time each operation takes to execute: ...
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1answer
64 views

RAM and data copying/moving

I was wondering about the copying/moving of data in RAM and I couldn't help but thing about the possibility of having the RAM process basic memory operations such as copying/moving of memory, if ...
0
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1answer
128 views

How to program pentium CPU [closed]

I have two perfectly good CPUs-one a Pentium m, the other a Pentium III-and they're just sitting in antistatic bags and bubble wrap doing nothing. I want to use them for SOMETHING, I know their ...
0
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1answer
93 views

How to test OpenSPARC CPU?

There are several open-source general-purpose CPUs, and the most advanced of them seems to be OpenSPARC T2 (correct me, if I'm wrong). I want to find out, with what effort I can build a machine, ...
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2answers
67 views

Processor Budgeting

How do I figure out if a microcontroller has enough processing speed to handle particularly "intensive" tasks? Specifically, I am a university student looking to design a robot that uses OpenCV and a ...
2
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1answer
83 views

CPU and clock rate

As I understand it, CPUs generate electrical pulses using a quartz crystal. The rate the pulses are generated (taking into account various multipliers) give the processing speed which all components ...
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4answers
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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 ...
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2answers
90 views

How many people might have been involved in the design of the Macintosh SE? [closed]

It is really difficult for me to know how many people were in charge of the development of this electronic wonder. When I'm struggling to properly comprehend transistors and how they work, these ...
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2answers
160 views

Why long pipelines are preferred over high CPU clock?

Why modern CPU vendors prefers increasing the maximum length of the pipeline over increasing the clock? Accordingly my understanding, increasing either increases the number of gate switches and so ...
60
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7answers
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What limits CPU speed?

I've recently talked with a friend about LaTeX compilation. LaTeX can use only one core to compile. So for the speed of LaTeX compiliation, the clock speed of the CPU is most important (see Tips for ...
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6answers
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How does a non-FPGA (ie a PC with a CPU, RAM, hard drive) mimic logic gates?

I know that an FPGA uses look-up tables (LUTs) to synthesize logic gates. A LUT is a block of RAM that is indexed by a number of inputs. The output is the value stored at that memory address. The ...
3
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2answers
196 views

Why does Intel looks so advanced compared to other foundries, engraving fineness-wise? [closed]

Latest chips from Intel were 22nm, and they are now targeting 14nm (coming in 2014 or 2015 it seems). On the other hand, Global Foundries or TSMC struggle since several years to go beyond the 28nm ...
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1answer
685 views

Were can I find a simple CPU Design tutorial / book? [closed]

I basically want to know how to make(In hardware and in a simulator) a simple CPU. A book that covers low level stuff like, like logic gates, and more high level stuff like a complete CPU. Ive tried ...
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1answer
438 views

What are these hardware components, and how do I control them?

My father received a video card in the mail last week. He gave it to me and I dismantled the card to get to just the video player and other components. The labels here are based on my experience ...
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1answer
73 views

What defines whether a CPU should be in LGA of PGA package?

All modern Intel CPUs I know are in LGA package. At the same time, AMD CPUs mostly are in PGA packages, with only server ones packaged in LGA. What are the reasons for Intel to use and AMD to not use ...
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2answers
483 views

AC/DC 4W vs 2A GSM transmission bursts

I have a big problem with the power supply of a SIM900. I designed my own board with a 220VAC-5VDC tracopower, an ARM9 CPU, and a GSM/GPRS SIM900 module. The output of the tracopower is 5V - 800 mA ...
0
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1answer
315 views

Why a lower voltage is better for modern fast CPU and other similar chips?

I started to use computers in the 1980's. As far as I remember 8bit CPUs of those times like Z80 were often powered by 5 V and used the same voltage for I/O signals. Later CPUs run at higher speeds ...
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3answers
91 views

Is quantum tunneling in transistors patterned?

Quantum tunneling is a problem when engineering a nano scale transistor. Generating random numbers is a common issue in computer science. I'm not an expert in either of these fields, but to someone ...
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2answers
209 views

PCI-Express Processor/Co-processor cards [closed]

I am hoping someone might be able to help: In the days when I started with computing (C64 and later Amigas) expansion slot cards with co-processing ability were relatively common. I am looking for ...
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3answers
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Why is L1 cache faster than L2 cache?

I'm trying to understand why certain CPU cache memories are faster than others. When comparing cache memory to something like main memory, there are differences in memory type (SRAM vs DRAM), and ...
0
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1answer
93 views

Hardware accelleration for Python dict?

I wondered if it were possible to accelerate in hardware the Python dict? Dicts are mappings between a key and value that form a large part of the backbone of how Python works. Everything is an ...
0
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1answer
71 views

how the CPU start by execution stored in motherboards flash memory chip [closed]

I had read that at start, the CPU program counter register is fill with F000. I though that: PC registers contain the next instruction address. This address is send to the address bus and value ...
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2answers
765 views

How does a GPU/CPU communicate with a standard display output? (hdmi/dvi/etc) [closed]

I am interested in how the cpu/gpu presents (to whatever equipment that it does) video data after it has been processed. I have been told that the video is processed by the cpu/gpu and then sent to an ...
2
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1answer
122 views

Dynamic energy and dynamic power in microprocessors

In a class I'm learning about dynamic energy and dynamic power and the notes seem to be incomplete. ...
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2answers
102 views

Programming with ARM without microcontroller context [closed]

I want to make an application that will use ARM CPU. Am I bound to using microcontrollers? The thing is the microcontrollers that have ARM as a base are really big in physical size. Can I create a ...
21
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3answers
4k views

How can an FPGA outperform a CPU

I hear of people using FPGAs to improve performance of systems that do things like bit-coin mining, electronic trading, and protein folding. How can an FPGA compete with a CPU on performance when ...
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1answer
133 views

Combining CPU and RAM on stacked silicon

Xilinx developed a way to combine multiple dies in a single package by using a silicon interposer (I don't know whether they're actually are the first ones to do this). This way, they achieve huge ...
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2answers
108 views

How many electrons does it take to switch on a transistor [closed]

How many electrons does it take to switch on a transistor, I read somewhere that Inel had made some electrical "paths" so small that they can allow only individual electrons to flow at a time, or ...
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1answer
98 views

CISC, microcode execution flow

Say we have 16 bit processor and such CISC instruction: 0001 0010 0100 1000 As far as I understood from the answer on related question In the process of decoding, this CISC instruction will be ...
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1answer
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ARM9 vs ARM11 performance? [closed]

This may be a loaded question, but is there a general understanding of the performance increase per clock between ARM9 and ARM11? Say, for a math-heavy function (FFT)? Thanks!