Electrical Engineering Stack Exchange
Electrical Engineering Stack Exchange

Questions tagged [hard-drive]

Anything related to hard disk drives (HDDs), a.k.a. hard-disks or hard-drives (HDs), i.e. electromechanical devices often found inside computers used as secondary storage (mass-storage). They can store information in digital form by magnetizing tiny areas of magnetic material with which the their internal disk-shaped rotating platters are coated.

Anything related to hard disk drives (HDDs), a.k.a. hard-disks or hard-drives (HDs), i.e. electromechanical devices often found inside computers used as secondary storage (mass-storage). They can store information in digital form by magnetizing tiny areas of magnetic material with which the their internal disk-shaped rotating platters are coated.

See also Wikipedia on hard disk drives.

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How do hotswapping computer parts work?

Computers support hotswapping so that a user can replace a harddrive while the system is running. Is that mostly software just powering off the harddrive or is it some special hardware involved? If there were not special hardware then I suppose that…
Niklas Rosencrantz
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How can I spin an old HDD motor?

I've stripped out an old IDE (40 Pin) HDD from 1998 for use in a POV display project (Gr. 12 Computer Engineering), and I've been trying to spin it up. The problem is that the HDD motor is brushless DC, so it requires more than just a ground and…
Alex
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How is the state of a bit position on a hard drive measured?

Firstly, I am not the EE type, but I do have a petty good foundation on physics work on a pretty low level. I was wondering what mechanism it is that measures the magnetic indentation on hard drive platter (if that's even the case), and/or the…
Chad Harrison
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Is it correct that in a hard disk both surfaces of each disk are capable of storing data?

I have read that in a hard disk both surfaces of each disk are capable of storing data except the top and bottom disk where only the inner surface is used. Is it correct if yes then why is are there read/write heads on top and bottom? From CBSE…
Anshul Gupta
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How big a magnet do I need to wipe my portable HDD?

According to this article, I need a really big magnet to wipe the data off my HDD. Thing is, I don't know how strong a "laboratory degausser" is, so I'll ask it in my own terms: I have a pair of magnets that would crush my fingers if I let them…
anonreview
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Where can I find XT-IDE (8bit IDE, XTA) specifications?

I have an old hard drive and would like to try to read the data from it. The hard drive is IDE, but it is the old version of IDE, called XTA and it is only 8 bits wide (compared to "normal", 16bit IDE). It is also incompatible with the modern…
Pentium100
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What exactly are 'pins'?

I actually ran into this question just a few moments ago: https://serverfault.com/questions/12025/intro-to-laptop-hard-drives The first answer is the one that caught my attention. Apparently, there are pins created for data flow (information) and…
Dark Templar
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Is it possible to read erased flash memory?

In hard disks, a "quick format" does nothing to the actual data on the disk - just clears the FAT (file allocation table), which then appears as a "blank disk" to the user. Therefore, it is fairly easy to ignore the FAT and read that data. Although…
rdtsc
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hard drive head/seek motor with Arduino?

I can see there are many writings on line for using an Arduino to control a 4 or 6 wire stepper motor, that spins the platter in side an IDE hard drive. I want to control the seek read/write head motor instead, can this be done? I'm struggling to…
jwbensley
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Reliable secondary storage for Raspberry Pi (or other such single-board computers (SBCs))?

Most SD cards have a fairly limited life (as in maximum number of read-write cycles), and in spite of wear-levelling, for relatively frequent disk update applications, would probably fail in a year or so, with reducing effective disk space, due to…
bdutta74
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Hard drive that has the ability to "read" old data while it performs a write?

Is there a hard drive (protocol command, specific model, etc.) that, while writing new data over old data, it "read"/return the old data back to the controller/OS? (Analogous to a simultaneous read-write). I've been looking up SATA/hard drisk…
eitan27
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Can I safely use a HDD in a car?

A few months ago I bought some new speakers and an amp for my Jeep. I made a little face plate with an ALPS potentiometer to control the volume and it has an iPod dock (no head unit, just the pot). A couple days ago I finally was able to order a…
Sponge Bob
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What is the maximum magnetic flux density a HDD can tolerate before data is corrupted?

Does anyone have hard numbers explaining the maximum number of Teslas a hard disk drive can tolerate before data will be corrupted. This forum says "a lot", which isn't super helpful. This one claims you need magnets that only governments have…
Zach Rattner
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Why do SSDs have a limited lifespan?

Why do solid-state drives even have a limited number of read/write cycles, usually 100,000-300,000 cycles? For hard-disk drives, it is understandable why they wear out. That is because they have moving parts that are in contact with each other. That…
CoastCity Lapse 00crashtest
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Why does reading 1 byte from hard disk has the same speed as operation reading 1000 bytes?

Two operations: read 1 byte from disk read 1000 bytes from disk Why exactly will they have approximately the same speed?
syntagma
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