Questions regarding architectures or design of specific parts, not consumer-related questions.

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0
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0answers
7 views

Monitor saying “No video input”, computer turns on however [migrated]

I really need help with this problem. Here's a detailed description of it: When I press the power button, the computer fires up with all the fans spinning and all the lights turning on. It'll ...
-3
votes
0answers
54 views

USB Cable Component [on hold]

I have a RAT 5 mouse which stops working when bending the USB cable and recently it stopped working completely. I decided to try a different USB cable to see if it works. However, I can't find any ...
15
votes
6answers
3k views

Breadboard computer

Is it possible to make a simple computer entirely with breadboards and basic electronic components? Is it feasible to, for example construct a scientific calculator in this way?
2
votes
2answers
322 views

Using PC audio to listen to electrical noise on power line?

I have done a bit of research on digital filtering and I was wondering if it would be possible to use the audio hardware of my computer tu listen to the electrical noise on my powerline ? If it is ...
0
votes
1answer
72 views

How much faster would optical computation be?

If (when) we could figure out a way to do computations with light as opposed to electrons within circuits, how much faster would our computers be?
1
vote
2answers
33 views

Piezo contact mic into iMac - avoid signal spikes

I've wired an external piezo as contact mic to the TRRS 3.5 jack of an iMac and it is working fine - BUT the signal will just randomly stop after hitting the contact mic several times too hard, so I ...
-4
votes
0answers
30 views

Need to know about apc ups AVR [migrated]

Due to high voltage my mac mini broke down. I am looking for cheap option and found this apc ups BX600CI. I read its specification which have AVR. I want to know what doest this mean. Its Input ...
2
votes
3answers
975 views

Is BeagleBone Black a microcontroller or computer?

I started working on BeagleBone Black, and I cannot find out whether BeagleBone is a microcontroller, or some kind of computer? If computer, what makes it a computer? I worked on different Cortex-M ...
1
vote
2answers
68 views

Is it possible to create a computer without sequential circuits?

Do computers (or FSMs) absolutely need sequential logic, or can it be done theoretically without? This seems impossible. Any proof of why it's not the case? (Showing that there can be no memory ...
1
vote
2answers
81 views

Historical electronic components used in computers

Early computers used vacuum tubes and relays as active components to process information. Later on, transistors replaced those as the main components used in computers development (transistorized ...
0
votes
0answers
47 views

Connecting a piezo/contact-mic to an iMac

I want to catch vibrations using a contact-mic made from a piezo element so I can measure vibration as loudness in OSX (Yosemite, iMac 14,2). But when I connect it to the iMac's 3.5 jack it ...
-7
votes
1answer
89 views

Is It Safe To Turn On a Dropped Laptop [closed]

My mother threw my Macbook out the windows and it landed on a flower pot. It has stayed intact however I'm reluctant to turn it on at risk of the hard drive getting damaged. Is it safe to power it ...
0
votes
2answers
70 views

Is it OK to use the USB 5v pin as power source?

I am doing some stuff in my case and I need a power source for one LED from inside my case. I looked up and there are two +5v pins on a USB header inside my case. Is it OK to use them as power ...
1
vote
0answers
25 views

find cache hit rate for direct mapped cache memory

I have this practice exam problem which I am having trouble with. I have gone over many slides but haven't been able to really get it. The question is I currently have an 8 block main memory with ...
1
vote
1answer
81 views

multicycle datapath vs single cycle datapath

I have a fairly simple question but have not been able to find a good answer googling. I understand how pipelining works by having 1 cycle per step, each instruction takes 5 cycles and they start ...
2
votes
1answer
54 views

Buck regulator to match an analog voltage

In desktop computers, it's common to have headers that control fans with a 0-12V analog output, capable of up to 1A. This works fine for one or two fans, but with more than three fans, you can exceed ...
0
votes
1answer
46 views

600 watts regulated DC for 3 seconds [closed]

In my area, due to frequent storms, there are frequently short mains power cuts lasting a second or two at most. While the shorter several-millisecond outages don't usually cause issues, the longer ...
0
votes
1answer
35 views

What are the meanings of the fields of this cache memory?

I have a cache memory simulator with this cache memory shown. The cache size is 64 bytes and the block size is 8 bytes. What is the decomposition into fields? If block size is 8 bytes, then ...
0
votes
2answers
68 views

Why does my mainboard power the cathode to turn the Power-LED off?

Close to all desktop motherboards have a pin header that is supposed to power an LED on the front of an enclosure with to indicate that the computer is on. In the documentation for my board, these ...
-1
votes
1answer
72 views

Why do laptops conduct electricity through the battery when they're plugged in and fully charged?

Electricity from an outlet goes through laptop batteries even when the battery is fully charged (to the best of my knowledge). This degrades the capacity of the battery (or so I've been told). It ...
0
votes
3answers
607 views

USB Flash drives up to 2TB? [closed]

I found USB Flash drives on aliexpress.com up to 2 TB. So much people bought them, and I'm reading feedbacks and 90% says: "It works perfectly, thanks", just a few customers have left a negative ...
1
vote
2answers
326 views

How to control the current output from usb slots of computers?

Is it possible to control output from a computer usb port so, for instance if I have a usb led I can make it blink or do whatever with it. Whenever I send a high signal it would glow and whenever I ...
1
vote
1answer
303 views

Micro and Nano Memory, Calculate Reducing Bits?

I ran into a question: in digital system with micro-programmed control circuit, total of 32 distinct pattern operation signal is ...
0
votes
1answer
28 views

Which are the spec bits in this cache?

I have a direct mapped cache of size S with the line size L. The cache is physically indexed and tagged. The physical address is 50 bits, numbered from 0 to 49 (with 0 being the least significant ...
0
votes
1answer
27 views

What is the difference between a virtually tagged and a physically tagged memory system?

I study computer architecture and this question came. What is the difference between a virtually tagged and a physically tagged memory system?
3
votes
1answer
97 views

adding two 64-bits number with m-bit carry ripple adder and multiplexer, a questions?

I ran into a question from computer architecture class. The professor says that for adding two 64-bit numbers A and B we use m-bit carry ripple adders and multiplexers such as following: and that ...
0
votes
0answers
27 views

Use Mosfet to switch secondary Powersupply on

I'm building a small computer that uses a Thin M-ITX motherboard. But I'm also using an GPU that is being powered by a secondary board. This secondary board has a regular 24-Pin ATX header. I know ...
0
votes
1answer
90 views

RPM v read/write speed

I am a developer using languages like C++ and .NET. I am trying to understand how computers work at a lower level. Say I have a hard disk that is 7400RPM and 150MB read/write speed. My book implies ...
2
votes
2answers
118 views

Using a toggle switch to act as push button

Basically I want to use a toggle switch to turn on my computer. I need some sort of circuit so that the toggle switch will act like a push button. IE, I turn on the toggle switch but it only sends a ...
1
vote
1answer
190 views

Reduce 160 Volts AC to 100 - 110 Volts AC (EL Wire Tape) Help

I am trying to put EL Wire Tape in a project that I am working on. I decided to go and build an inverter for 12VDC to 100VAC and that fell through. I couldn't find any guides that helped on EL Wire ...
-2
votes
2answers
181 views

Where is the best place I can go to learn everything about the electronics-side of computers? [closed]

Throughout my childhood, I grew up learning about electronics and computers. I am starting to get to the point where I want to incorporate my knowledge of both into a single project. I have tried ...
2
votes
2answers
73 views

Detecting TVs with PC's graphics card

I'm interesting of how can graphics cards detecting what type of TV has connected with S-Video? TVs sent some indefiniter signal back to the computer? And how it's working (protocols, signals, freq, ...
2
votes
3answers
162 views

Is hardware flow control necessary?

I want to communicate using a serial cable to a device that uses RTS/CTS flow control and 115200 baud speed. I want to use this Sparkfun TTL to rs232 adapter, but it has no RTS or CTS pins. What can I ...
0
votes
2answers
214 views

Can we observe addresses, data and other signals on the microcomputer buses by an oscilloscope, a LED or even an ordinary DC voltmeter?

Microcomputers are dynamic devices that are synchronized by a clock oscillator. So the signals (E, R/W, CS, A15-A0, D7-D0...) appear on their buses only for parts of a microsecond and, as the buses ...
0
votes
1answer
124 views

What is the purpose of the thick blue line in this schematic?

On this schematic for a Z80 computer, there appears to be a thick blue wire connecting some components together. What is it? Googling yields no results: here is the schematic
0
votes
1answer
439 views

Determining memory address width from memory size

Given a computer A with 1024 x 16 memory and a computer B with 16K x 32 memory, how big are the registers of an Accumulator, program counter, instruction, temporary register, address register, data ...
2
votes
3answers
106 views

Curious how does ALU addressing work like in Assembly code?

When writing assembly code, say R1 = R2 + R3, it is pretty easy to understand the addressing procedure because all registers are close to the ALU. But I find it hard to see how does the ALU go to the ...
1
vote
0answers
55 views

Design considerations for internal PC parts

I'm designing a PWM fan controller. It will be interally mounted inside a PC and will take power from the normal 4 pin Mate-N-Lock ("molex") connector. The on-board MCU and LCD will draw power from ...
0
votes
0answers
148 views

Can a zener diode be used to slow down a fan?

I often use a resistor to slow down a fan in older PC's, because these old computers are too noisy. Can a zener diode be also used to slow down a fan in a PC? As far as I know these small fans are ...
1
vote
1answer
175 views

How much RF-interference does a typical desktop computer produce? How much does a metal case without windows reduce it?

It's fairly common now to see desktop computers in cases with large windows cut in the sides. I've always been under the impression that if unshielded, computer equipment will produce a lot of radio ...
-1
votes
1answer
126 views

Parallel MAC unit based on modified booth algorithm

The below diagram is the parallel MAC structure. In parallel MAC both partial product addition and accumulation take place at same time. The partial product summation + accumulation unit of above ...
2
votes
1answer
291 views

What was the crysistor?

I'm reading through Jim Williams' "Analog Circuit Design: Art, Science and Personalities", and a mysterious component called a crysistor is mentioned. There are a few clues in the text, like the fact ...
1
vote
1answer
62 views

How do you reduce an 8 output ALU to a 4 or 3 output ALU?

I can implement the functions in the picture below, but then if I implement them independently, I would have 8 outputs to the mux. Our professors wants us to reduce the ALU to only 3 or 4 outputs, I ...
2
votes
2answers
1k views

How are microscopic transistors on microchips made?

How is something like a microchip which is already small as it is able to house even smaller transistors in the millions at such a micro-scale? It seems like such a feat for machine to be able to make ...
0
votes
1answer
133 views

What determines the maximum rotational speed of a hard disk drive?

Through my background research I understand that the limit on the rotation of a hdd is largely the product of heat and the specs of the physical disk, but I am puzzled by the round numbers advertised ...
0
votes
2answers
107 views

Average Cycles Per Instruction

We have two different computers with the same instruction set. There are three classes of instructions (A, B, and C) in the instruction set. Computer M1 has a clock rate of 80 MHz and Computer M2 has ...
-2
votes
2answers
142 views

Where does power in my laptop go when I disconnect the battery? [closed]

I have a laptop which, when put to sleep, sometimes enters a state of limbo, from which it can be neither turned off nor on, and the only solution is to disconnect the battery, reattach it, and turn ...
0
votes
1answer
980 views

Design and build a single board computer [closed]

I want to learn how to design and build a single board computer like the Raspberry Pi. I saw a DIY project on Hack-A-Day and design something like the board in the DIY project but a bit more ...
0
votes
1answer
111 views

Safely shutting down 19V mini PC when power fails

I am adding an Intel NUC (4"x4" i5 PC, 12-19V, 10A@19V) to my guitar effect pedalboard for all kinds of fun signal processing with Ableton Live and Max/Msp. I'm building a 12V 20A power supply using ...
0
votes
3answers
184 views

How hot can MOSFETs get before blowing up?

This is different from a lot of other stuff here, but I have a motherboard that has no MOSFET cooling, and when I touch them they burn my hands; they are probably 70-80C. I just want to know how long ...