Questions tagged [computers]
Questions regarding architectures or design of specific parts, not consumer-related questions.
1
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3answers
136 views
Getting CPU clock signal out of computer (as to measure externally) [on hold]
I've been searching on the internet some clock generator module capable of reaching up to 1GHz, when I just realized that the machine I'm using to search has one CPU with its own 2.5-3.0 GHz clock... ...
1
vote
3answers
82 views
How big does ground need to be? Step down from 5v10a to 1.2V 50a, do I need a 50 amp ground?
I'm just a layman. I was just thinking about CPUs in computers. They run at about 1, 1.5 volts or there about, sometimes even lower. Desktop cpus can take 90 watts, some 120 watts. That's close to 100 ...
0
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0answers
31 views
relay causing problem to controller
I have a relay which is electronically controlled by a computer (Odroid) and used as a switch for a high power circuit. The computer and the other circuit are powered with different plugs on the same ...
0
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3answers
150 views
LEDs in computer case are non-polar?
Normally I think of LEDs being polar and having a definite current direction, the "D" in LED standing for "diode".
However, in working with with a computer case recently, the front part of the case ...
-1
votes
3answers
160 views
Why aren't laptops with transparent displays a thing? [closed]
I just realized that the display on my 2012 Macbook Air is transparent. I had the screen brightness of the built in display on the lowest (off) while using an external monitor, and the sun came ...
1
vote
0answers
59 views
Non-Polarized Electrolytic Capacitor Replacement
To the best of my abilities, I'm trying to repair an Atari 800XL which was sold as "non working unit". I found a new graphics chip and it's working ok. I though that, since I had it opened up, it ...
1
vote
1answer
72 views
How does the computer's BIOS change the clock speed?
A computer's BIOS can change either the multiplier value or the (FSB) clock frequency to overclock or underclock a CPU. While overclocking by changing the multiplier value is easier and in more often ...
0
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2answers
66 views
Is it possible to blink an LED with just a USB data cable and a transistor?
Sorry if this is a dumb question, I am new to electronics and was looking at diagrams of USB cables and wondered,
"Could you use the low voltage data wires on a usb and a MOSFET or something to ...
0
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0answers
68 views
Connect wire to earth when PC power led is on
I am trying to make a mod to a computer case. What I want is that every time the computer power led lights, another cable connects to earth. Something like this.
I read the motherboard outputs 5V for ...
1
vote
4answers
145 views
Does computer memory record the zero binary state?
It's been two years since I started reading about electronics and computer circuits. I fell in love with the homemade computers and the possibility of building one by myself.
You will see: When ...
0
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2answers
38 views
AS6C62256A SRAM Usage
I'm in the process of creating a RAM module for a breadboard computer I'm making. The RAM I've decided to use is the AS6C62256A SRAM chip, in 32K x 8. Here's the datasheet: https://www.alliancememory....
6
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5answers
4k views
Why are DIMMs not equipped with a heat sink like a CPU?
I know that a DIMM is composed of a set of chips that contain control logic managing the decode and prefetching memory operations. According to a product specification, I found that newer RAM works at ...
0
votes
1answer
98 views
What is a carriage return? [closed]
I have this question where they ask you:
Find a table of ASCII codes on the internet and give the ASCII code for each of the following in both denary and hexadecimal:
Uppercase R Denary ...
2
votes
2answers
131 views
Can i replace 3 (parallel) capacitors 16v 1800uf with 16v 2200uf?
The motherboard model is G31T-M REV:1.0 .
The circuit is for the 4-pin 12v power rail coming from the power supply.
I'm replacing these because they are very bloated,
It's quite a miracle that the ...
0
votes
2answers
87 views
What is “2DIN” in the context of car radio interfaces? [closed]
I want to install a custom computer in lieu of my radio in my 1996 Volvo 850. I have seen various kits, such as one offering a barebones "2DIN" computer. What does this mean?
(My main concern is ...
1
vote
4answers
166 views
Dim and “unblink” a pc power LED?
I just built an HTPC. It's got a bright white power-on indicator LED that is in fact needlessly bright and, which is worse, blinks when the pc is in suspend mode. I want it to be less eye-catching.
I ...
0
votes
2answers
108 views
What is the voltage that goes through a computers power switch?
I'm hooking up a microcontroller to be able to turn a bunch of computers on/off remotely. This is via the soft switch on the motherboard which doesn't carry any kind of load.
Looking at relays, the ...
-2
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3answers
96 views
Store more than 4 bit data on 8 bit bus
I don't have electrical background, but yesterday after watching some videos on youtube about old 8 bit computer, I have some question about how they work.
8 bit computer has 8 bit bus data which ...
3
votes
2answers
1k views
Wiring Diagram for Split Micro-USB Cable? [closed]
I have a customer who is looking for a split Micro-USB cable, which has one USB-A host connector on one end and two Micro-USB cables on the opposite end (they will be plugging into cameras). Can I ...
1
vote
1answer
225 views
Why does this component on my Arduino UNO heat up?
Every time that I plug my Arduino into the computer, this chip immediately gets burning hot, way too hot to touch, this wasn't something that i noticed happened after a particular event, I just ...
0
votes
2answers
232 views
Z80 computer design peer-review [closed]
this is a re-post as I was unable to get any help on other forums. I have designed and built a simple Z80 computer system with 32K RAM, Z80B at 4mhz, 32K ROM, and a UART. The only problem with it is ...
20
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6answers
9k views
Does water actually damage or only temporarily disable electronics until drying out?
Does water leave any damage after drying out?
If it does, where and how exactly does it? How can it be repaired?
2
votes
1answer
162 views
Computer won't post / Beep unless Unplugged for a few hours [closed]
I'm experiencing this issue for almost a year now. It is slowly getting worse. My motherboard is Gigabyte GA-Z77X-D3H and my PSU is Corsair CX600. The source of the problem most likely has to do with ...
5
votes
2answers
199 views
How do PC sound cards cope with headsets of different impedance?
I recently got a PC motherboard that advertises a "smart" audio amplifier chip to manage headsets with different impedance:
However, I have never had a problem with headphones before.
Will I notice ...
0
votes
1answer
121 views
Ram USB storage device [closed]
I have been searching for a storage solution that can be written to an infinite amount of times, and RAM comes up every time.
So is it possible to connect RAM to a controller and use it like a ...
3
votes
1answer
129 views
Why would ALU Output be Asynchronous with Input Change?
Wikipedia states "An ALU is a combinational logic circuit, meaning that its outputs will change asynchronously in response to input changes."
But, the definition of a combinational logic circuit is: "...
0
votes
1answer
226 views
Object Recognition and tracking [closed]
I've been trying to make a butter passing bot, like the one from rick and morty.
https://www.youtube.com/watch?v=X7HmltUWXgs
I can do pretty much everything on there, but I need someone to help with ...
2
votes
1answer
205 views
What causes failure in longer USB cables?
I wired up some USB-C 2.0 to USB-A 2.0 cables, and tested the maximum length I could get out of them when connecting a PC (host, USB-A) to an external hard drive (device, USB-C). I got stable power ...
0
votes
1answer
265 views
Wiring a USB-C (host) cable question
I have wired some custom USB-C cables from scratch in the past, where the USB-A connector is plugging in to a host PC. If I wired a USB cable where the USB-C connector was plugging into a host ...
0
votes
0answers
170 views
1-bit SRAM circuit issues
I've been doing a lot of research on making a DIY SRAM circuit (1 bit for now). I've been primarily looking at http://codeitdown.com/diy-ram-memory/
and followed this circuit diagram
and I've ...
0
votes
1answer
107 views
custom built computers
When buying an off-the-shelf computer I assume it gets tested to make sure for example that the power supply meets the regulation, the battery and usage does not exceed the limits etc.
How does it ...
1
vote
2answers
235 views
Splitting induvidual WS2812B LEDs
My motherboard has a WS2812B header for use in addressable RGB LED strips. However I am not using them for those strips, as instead I would like to use the signal to separately control several other ...
1
vote
2answers
2k views
Problems trying to wire a USB-C cable
I have been trying to figure out how to custom wire a USB-C to USB-A cable for a while, with no luck.I have tried some different connectors, but wanted to get some outside ideas on what I might be ...
3
votes
2answers
8k views
3 wires on a (bipolar) DC plug - what are they for?
If got this cable as a power plug for my DELL XPS 15. I want to hook it up to a different power source.
But what are the 3! wires for on a bipolar plug?
1
vote
2answers
520 views
Shared support chips and tooling between 16 and 32-bit computers
Can a production line for a 16-bit computer save significantly on unit cost by sharing support chips and tooling with another 16-bit computer, to a greater extent than if it went 32-bit?
To be ...
0
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1answer
2k views
How can I wire a Mini-USB to Micro-USB cable?
I'm trying to figure out how to connect the pins from a Micro-USB connector to a Mini-USB connector. I'm assuming it's more complex than just connecting the +5V to the +5v, GND to GND, D- to D- and D+ ...
0
votes
1answer
575 views
What is the difference between programing with JTAG and USART interfaces?
I understand there are 2 interfaces to programming NanoMind A712 computer: JTAG and USART. But what is the difference in programming the computer in JTAG or USART interfaces?
Datasheet: See page 10: "...
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2answers
1k views
Data transfer from Microcontroller to computer [closed]
I'm looking for a good link to data from Microcontroller to computer.
I do not know what kind of communications is suitable for me.
I need a link which has a bit rate more than 50 Mbit/sec. and also ...
0
votes
5answers
108 views
How can I calculate how much my desktop PC costs to run for an hour?
I was torn on whether to post this to here or Math.SE, so feel free to move it as appropriate.
I recently got hold of a power usage monitor in order to calculate how much my PC costs to run a given ...
-5
votes
1answer
126 views
What does a computer program (for example, Word) do, when the user does not type anything? [closed]
That's the whole question. When I type anything the interrupt comes into play. But what happens when I do not type anything but the program still runs?
0
votes
2answers
258 views
Can I use a tactile switch as computer power switch? [closed]
I was thinking of replacing my broken power button in my CPU with a tactile switch connected to the power cord on the motherboard, but I was wondering if that would work without any harmful ...
0
votes
2answers
369 views
Kill A Watt reports 2.5 amps but with a power factor of 0.4 [closed]
My computer isn't using anywhere near 2.5 amps (It's using less than half that) however my kill a watt reports 2.5 amps with a power factor of 0.4. This computer needs to run on a 2 amp circuit, would ...
0
votes
1answer
217 views
Effect of Voltage sag on IT Equipment [closed]
Let say I have IT equipment that is rated for 100V to 240V. I plug it into a 208V receptacle that it unprotected (no UPS or surge suppression). What would happen if there were a voltage sag on 40%. ...
0
votes
1answer
384 views
Fan speed control - Voltage (0-5V) to PWM (0-100%) with minimum value
I need to control 12V fans (w/ PWM so 4 pin) with a laptop motherboard which originally had 5V fans (3-pin only so voltage-controlled), so I want to:
use external supply of 12V (or internal from ...
0
votes
1answer
60 views
Viability for thermoelectric cooling in a computer setting
I have a very powerful server computer that needs to be running 24/7, and the twin watercooled (with multiple fans) CPU is still overheating largely because the room it's stored in gets quite hot in ...
21
votes
1answer
1k views
What is this transformer-like component, and why is it not really connected?
Recently, a power surge took out a few components in my PC's ATX power supply. While repairing (I hope), one component in the power drew my attention. I'm an electronics engineer, but I'm confused ...
0
votes
1answer
146 views
Wiring for cutom USB cables
I am working on DIY-ing a handful of USB cables (USB-A to mini for PC peripherals and phone charging), and I'd like a professional take on two dilemmas that I have:
1) I have the option of using ...
2
votes
3answers
151 views
Why are computers not cubes? [closed]
If you look at the old NeXT Computer, two things jump out about the form factor: it's a cube, and it looks really cool. Ditto the original Connection Machine.
If you look at, well, absolutely every ...
2
votes
0answers
80 views
Can anyone tell me what other computers used this floating-point format?
I have discovered that the DEC PDP-10 used a floating-point format that differed from IEEE-754 in an interesting way.
IEEE-754 is like sign-magnitude representation. The only difference between a ...
1
vote
2answers
61 views
re-attach battery driven gamepad to PC power supply
There are times at that I get mad about empty AA batteries or accumulators losing their capacity too early. And since the gaming computer is running anyway, I thought about using one of the molex ...
