Author Topic: This Janet Jackson BASSLINE breaks laptops  (Read 4970 times)

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Offline ebastler

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Re: This Janet Jackson BASSLINE breaks laptops
« Reply #25 on: January 08, 2023, 12:54:27 pm »
Going as far back to the source of this story as I can, I find the following on Raymond Chen's blog, https://devblogs.microsoft.com/oldnewthing/20220816-00/?p=106994:

Quote
A colleague of mine shared a story from Windows XP product support. A major computer manufacturer discovered that playing the music video for Janet Jackson’s “Rhythm Nation” would crash certain models of laptops. [...]

"I heard this from a colleague, who had heard it from someone at some major computer manufacturer...". Oh, this is how all urban legend stories start? Oh, right...  ::)
 

Offline Buriedcode

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Re: This Janet Jackson BASSLINE breaks laptops
« Reply #26 on: January 09, 2023, 01:20:21 am »
Note, my HP laptop has an accelerometer feature for the HD protection which can be enabled/disabled in the advanced HP tools.  I wonder if the music is just tripping such a protection feature in these laptops.

I'm pretty sure most 2.5" drives have shock sensors, at least in every one I have seen/repaired. They look like ceramic resonators, a few of them are used to park the heads before impact.
https://www.murata.com/en-global/products/sensor/shock

I suspect you're correct.  It's either mems accelerometers (which are, what 15 years old now?) or the above which have been about since 2.5" drives.  Either way I can't imagine it being particularly damaging, especially as few laptops have any real audio power to their speakers.  Interesting video, but "breaks" is a stretch.
 

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Re: This Janet Jackson BASSLINE breaks laptops
« Reply #27 on: January 09, 2023, 05:14:55 am »
I call bullshit as well.
I read the story elsewhere (can't find it right now, sorry), but the point was that extremely agressive copy protection wreaked havoc on Win machines (as always). It's a Big Music plus Microsoft thing.
The story is not about DRM but about vibration at certain frequency causing HDD malfunction. FWIW HDDs are sensitive to vibration, so the story has some plausibility.

Yep. The less plausible part is that the laptop's speakers would have high enough output for low frequencies to cause any issue.
Those tiny speakers usually have a pretty poor low-freq response. So it sounds pretty unlikely to be able to couple vibration with enough amplitude to cause damage to a hard drive. So yeah, not impossible but rather unlikely.


But it's a funny story nonetheless.

Yep, I'm in that camp as well. Technically possible, but highly unlikely in practice.
The hard drives would have been vibrationaly frequency sweeped during operation to verify this isn't an issue.

 

Offline Ed.Kloonk

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Re: This Janet Jackson BASSLINE breaks laptops
« Reply #28 on: January 09, 2023, 05:43:08 am »
Accelerometers with built in free fall detection is actually a big feature, like this one:

https://www.st.com/resource/en/design_tip/dt0100-setting-up-freefall-recognition-with-sts-mems-accelerometers-stmicroelectronics.pdf

Yes, some of the settings will directly trigger the interrupt output pin within a detected 50-100hz sweep.

(Googled...)


If the sensitivity of the laptop's accelerometer was set too high, yes it will pick up audio just like a microphone as you can see in the .pdf that it is sensitive way into the 400hz region.  Have a laptop where the accelerometer is next to the speaker, yeah, it's gonna trigger when set to it's minimal quickest response sensitivity setting.

At the risk of being pedantic, when they say it "turns off the hard drive", I wonder if they mean park the heads.

One of my computer dealers used to say that the sudden power outage forces a head park, too many of those and it's goodnight drive since it's not good for the heads to do that too often. That's what I was told, don't know if it's bullshit or not. The accelerometer could be performing this task, but it swings the heads pretty hard into park, as I understand.
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Online BrianHGTopic starter

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Re: This Janet Jackson BASSLINE breaks laptops
« Reply #29 on: January 09, 2023, 05:50:34 am »
I'm pretty sure most 2.5" drives have shock sensors, at least in every one I have seen/repaired. They look like ceramic resonators, a few of them are used to park the heads before impact.
https://www.murata.com/en-global/products/sensor/shock

I suspect you're correct.  It's either mems accelerometers (which are, what 15 years old now?) or the above which have been about since 2.5" drives.  Either way I can't imagine it being particularly damaging, especially as few laptops have any real audio power to their speakers.  Interesting video, but "breaks" is a stretch.
These Murata shock sensors mounted on the HDs controller board probably just temporarily park the HD head.  Such an event might even be logged in the Windows Event viewer.

However, the Laptops with the feature of a mems Zero G free-fall and shock detection sensor are placed on the laptop's motherboard.  Some of those probably have a kill the system power function.
« Last Edit: January 09, 2023, 05:52:32 am by BrianHG »
 

Online BrianHGTopic starter

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Re: This Janet Jackson BASSLINE breaks laptops
« Reply #30 on: January 09, 2023, 05:54:33 am »
Accelerometers with built in free fall detection is actually a big feature, like this one:

https://www.st.com/resource/en/design_tip/dt0100-setting-up-freefall-recognition-with-sts-mems-accelerometers-stmicroelectronics.pdf

Yes, some of the settings will directly trigger the interrupt output pin within a detected 50-100hz sweep.

Maybe I should buy one of these sensors, mount it on a small PCB & scope it with different settings playing Janet Jackson's song...
 

Offline AVGresponding

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Re: This Janet Jackson BASSLINE breaks laptops
« Reply #31 on: January 09, 2023, 06:09:20 am »
I call bullshit as well.
I read the story elsewhere (can't find it right now, sorry), but the point was that extremely agressive copy protection wreaked havoc on Win machines (as always). It's a Big Music plus Microsoft thing.
The story is not about DRM but about vibration at certain frequency causing HDD malfunction. FWIW HDDs are sensitive to vibration, so the story has some plausibility.

Yep. The less plausible part is that the laptop's speakers would have high enough output for low frequencies to cause any issue.
Those tiny speakers usually have a pretty poor low-freq response. So it sounds pretty unlikely to be able to couple vibration with enough amplitude to cause damage to a hard drive. So yeah, not impossible but rather unlikely.


But it's a funny story nonetheless.

Yep, I'm in that camp as well. Technically possible, but highly unlikely in practice.
The hard drives would should have been vibrationaly frequency sweeped during operation to verify this isn't an issue.

FTFY...
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Online BrianHGTopic starter

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Re: This Janet Jackson BASSLINE breaks laptops
« Reply #32 on: January 09, 2023, 06:34:20 am »
I call bullshit as well.
I read the story elsewhere (can't find it right now, sorry), but the point was that extremely agressive copy protection wreaked havoc on Win machines (as always). It's a Big Music plus Microsoft thing.
The story is not about DRM but about vibration at certain frequency causing HDD malfunction. FWIW HDDs are sensitive to vibration, so the story has some plausibility.

Yep. The less plausible part is that the laptop's speakers would have high enough output for low frequencies to cause any issue.
Those tiny speakers usually have a pretty poor low-freq response. So it sounds pretty unlikely to be able to couple vibration with enough amplitude to cause damage to a hard drive. So yeah, not impossible but rather unlikely.


But it's a funny story nonetheless.

Yep, I'm in that camp as well. Technically possible, but highly unlikely in practice.
The hard drives would should have been vibrationaly frequency sweeped during operation to verify this isn't an issue.

FTFY...
For a HD, or anything else, sweep alone isn't enough, you need some chaotic white noise in there as well.
 

Online wraper

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Re: This Janet Jackson BASSLINE breaks laptops
« Reply #33 on: January 09, 2023, 07:16:14 am »
At 6:50 Dave was able to sort of reproduce the error with more detailed results with a test tone a bit later.

 

Offline Halcyon

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Re: This Janet Jackson BASSLINE breaks laptops
« Reply #34 on: January 09, 2023, 07:50:04 am »
Note, my HP laptop has an accelerometer feature for the HD protection which can be enabled/disabled in the advanced HP tools.  I wonder if the music is just tripping such a protection feature in these laptops.

I think this is it.  The video in Adam's video @1:33 shows the laptop powering off completely.  If the HDD crashed, you might expect a lock up of the system or a BSOD, not a power down.   I know that the accelerometer protection on my older Lenovo laptop powered the whole system down.  Not sure why - maybe to provide more consistency for the user after a drop (a hung system is worse than a powered-off one?)

I'd suggest this is poor design, or something was wrong. Laptops are designed to be portable, moved, tilted, picked up or otherwise shoved about. I'd be pretty pissed if my laptop powered off every time I moved it. It would be going right back to the shop for a full refund.

Hard disk interfaces (and operating systems) have for decades been designed in such a way that if there is a delay in accessing media, then the system will cope with that and simply wait.
« Last Edit: January 09, 2023, 07:53:57 am by Halcyon »
 

Online BrianHGTopic starter

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Re: This Janet Jackson BASSLINE breaks laptops
« Reply #35 on: January 09, 2023, 08:18:28 am »
Note, my HP laptop has an accelerometer feature for the HD protection which can be enabled/disabled in the advanced HP tools.  I wonder if the music is just tripping such a protection feature in these laptops.

I think this is it.  The video in Adam's video @1:33 shows the laptop powering off completely.  If the HDD crashed, you might expect a lock up of the system or a BSOD, not a power down.   I know that the accelerometer protection on my older Lenovo laptop powered the whole system down.  Not sure why - maybe to provide more consistency for the user after a drop (a hung system is worse than a powered-off one?)

I'd suggest this is poor design, or something was wrong. Laptops are designed to be portable, moved, tilted, picked up or otherwise shoved about. I'd be pretty pissed if my laptop powered off every time I moved it. It would be going right back to the shop for a full refund.

Hard disk interfaces (and operating systems) have for decades been designed in such a way that if there is a delay in accessing media, then the system will cope with that and simply wait.
  I completely agree.  I saw a youtube video illustrating the bug on a Toshiba laptop.  What was illustrated that the windows HD file access was paused a few times while playing the song.  However, this just may have been just a slow laptop, or swap-file access.

  You do know that free-fall mems accelerometers cannot sense gravity.  All they can can do is measure acceleration in 3 axis.  Their measured acceleration needs to go through a complex formula to determine if there is a true drop.  Calculation on the older mems units, like the .pdf I linked to, which has an illustration of the waveform as a free fall begins, continuously performs this calculation built into the mems IC and there are a set of controls to set the filter's 'window' frequency rolloff, response time and threshold sensitivity.  When set high enough, looking at the waveform provided in the .pdf, it is something which can be easily tricked even with a very low volume, but particular sound which mimics that window's opening of an object beginning to accelerate exactly 9.8m/s2.  All other signals are rejected by the 'free-fall' detector's formula.  This means no solid tone.  No impact.  No closing laptop lid.  No lifting up, or lowering down of the laptop.  You need the effect of Earth specific gravity drop.  Note that other mem accelerometers, like those from NXP, had to use a MCU to run the calculation to detect the free-fall pattern and again, there are online papers on how to do this while rejecting all other forms of acceleration.
« Last Edit: January 09, 2023, 08:21:55 am by BrianHG »
 

Offline mushroom

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Re: This Janet Jackson BASSLINE breaks laptops
« Reply #36 on: January 09, 2023, 02:10:59 pm »
Wasn't a laptop, wasn't Janet Jackson.
20 years ago, I repurposed as PC speakers a pair of small shelf speakers I built in the mid '80. Put them on the desktop. Also was sitting on the desktop an external 5.25" backup HDD. As soon as I played some music, the HDD died.
Just desk resonance, and it didn't take long !

Can't remember what I was testing the speaker+amp with. At this time, probably some BNWOHM or hair metal MP3 the mule brought to me...
 

Online SiliconWizard

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Re: This Janet Jackson BASSLINE breaks laptops
« Reply #37 on: January 09, 2023, 07:54:26 pm »
I call bullshit as well.
I read the story elsewhere (can't find it right now, sorry), but the point was that extremely agressive copy protection wreaked havoc on Win machines (as always). It's a Big Music plus Microsoft thing.
The story is not about DRM but about vibration at certain frequency causing HDD malfunction. FWIW HDDs are sensitive to vibration, so the story has some plausibility.

Yep. The less plausible part is that the laptop's speakers would have high enough output for low frequencies to cause any issue.
Those tiny speakers usually have a pretty poor low-freq response. So it sounds pretty unlikely to be able to couple vibration with enough amplitude to cause damage to a hard drive. So yeah, not impossible but rather unlikely.


But it's a funny story nonetheless.

Yep, I'm in that camp as well. Technically possible, but highly unlikely in practice.
The hard drives would have been vibrationaly frequency sweeped during operation to verify this isn't an issue.

If it did happen, then it would essentially be a defect with the HDD design (and testing), and it's very typical, and very "clickbaity", to carefully avoid pointing to the HDD vendor and amuse people with a funny narrative. Yeah, it's just the bassline, dudes. ::) No wonder the topic is being relayed at an amazing speed by a ton of high-viewed Youtubers.


 

Online SiliconWizard

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Re: This Janet Jackson BASSLINE breaks laptops
« Reply #38 on: January 09, 2023, 08:06:37 pm »
  You do know that free-fall mems accelerometers cannot sense gravity.  All they can can do is measure acceleration in 3 axis.

They do not sense gravity, but they can determine it indirectly by sensing the reaction force when the device is stationary. It's actually an annoyance when you want to determine linear acceleration only with those accelerometers. A MEMS accelerometer lying flat (and still) on a table will measure ~1g along the Z axis, and close to 0 along X and Y.

In pure free fall, the measured acceleration on all 3 axis will be close to 0. So you can detect free fall. To some degree.

Now it's not 100% accurate, but merely taking the norm of the measured acceleration vector is usually enough to determine free fall. When the device is standing still on a surface, whatever its orientation, the norm will be close to 1g. When it's in free fall, it will be close to 0g. Of course there can be specific motions that could somewhat make this very simple approach fail, but it's usually good enough.
 

Online wraper

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Re: This Janet Jackson BASSLINE breaks laptops
« Reply #39 on: January 09, 2023, 09:11:23 pm »
If it did happen, then it would essentially be a defect with the HDD design (and testing), and it's very typical, and very "clickbaity", to carefully avoid pointing to the HDD vendor and amuse people with a funny narrative. Yeah, it's just the bassline, dudes. ::) No wonder the topic is being relayed at an amazing speed by a ton of high-viewed Youtubers.
Actually its almost a miracle hard disks can work at all with vibrations present considering track width in nanometers.
 
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Online tom66

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Re: This Janet Jackson BASSLINE breaks laptops
« Reply #40 on: January 10, 2023, 03:31:34 pm »
Actually its almost a miracle hard disks can work at all with vibrations present considering track width in nanometers.

Even more miraculous is devices like the original iPod with 20 ~ 160GB micro hard disks inside them.  These devices can play music while you are cycling and in my limited experience they never dropped out.  It's almost a shame such a device lost out to flash memory, of course flash is technologically better, but it's *boring*.
 
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Online BrianHGTopic starter

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Re: This Janet Jackson BASSLINE breaks laptops
« Reply #41 on: January 11, 2023, 05:18:54 am »
Even more miraculous is devices like the original iPod with 20 ~ 160GB micro hard disks inside them.  These devices can play music while you are cycling and in my limited experience they never dropped out.
No.  Apple's big thing about the IPOD is that their playback cache was stored in ram as .mp3 and that they had an hours worth of it which was loaded in around ~5 seconds.  If you stopped moving for a few seconds, the drive could power up, load the next hour of music, and go back to deep sleep saving the battery life.
 

Online tom66

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Re: This Janet Jackson BASSLINE breaks laptops
« Reply #42 on: January 11, 2023, 09:22:51 am »
No.  Apple's big thing about the IPOD is that their playback cache was stored in ram as .mp3 and that they had an hours worth of it which was loaded in around ~5 seconds.  If you stopped moving for a few seconds, the drive could power up, load the next hour of music, and go back to deep sleep saving the battery life.

Yes, I suppose that would help - but wasn't that more about power saving than anything?  You'd still need to spin the disk up if you like to skip songs a lot, and it didn't seem to have trouble when I did that. 
 

Offline Haenk

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Re: This Janet Jackson BASSLINE breaks laptops
« Reply #43 on: January 11, 2023, 11:00:20 am »
One of my computer dealers used to say that the sudden power outage forces a head park, too many of those and it's goodnight drive since it's not good for the heads to do that too often. That's what I was told, don't know if it's bullshit or not. The accelerometer could be performing this task, but it swings the heads pretty hard into park, as I understand.

I'd say that is nonsense - if powered down, the platters still spin, so the heads are still up in the air (so to speak); the arm itself snaps back into parking position almost immediatly (*way* faster than the spindown duration) and the heads are then stabilzed by some plastic spacers and above a "crash zone" on the platters. So sudden power loss is usually no problem (other than maybe data loss due to unwritten data). The arm mechanics is really extremely solid and AFAIR there were even drives that were powered down permanently for energy savings (early WD Green?), I think those had powerup/down-cycles (which are mechanically equivalent to a power loss, minus the platter motor) in the hundreds of thousands or even millions.
 

Offline MrMobodies

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Re: This Janet Jackson BASSLINE breaks laptops
« Reply #44 on: January 11, 2023, 11:08:06 am »
I remembered seeing a few laptops in the past with a rubber patch under or near the hard disk cover with a label on it hinting to absord shocks.

I wonder if that would help bit with the high pitched noise.
 

Online tom66

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Re: This Janet Jackson BASSLINE breaks laptops
« Reply #45 on: January 11, 2023, 11:09:09 am »
I'd say that is nonsense - if powered down, the platters still spin, so the heads are still up in the air (so to speak); the arm itself snaps back into parking position almost immediatly (*way* faster than the spindown duration) and the heads are then stabilzed by some plastic spacers and above a "crash zone" on the platters. So sudden power loss is usually no problem (other than maybe data loss due to unwritten data). The arm mechanics is really extremely solid and AFAIR there were even drives that were powered down permanently for energy savings (early WD Green?), I think those had powerup/down-cycles (which are mechanically equivalent to a power loss, minus the platter motor) in the hundreds of thousands or even millions.

Not sure how mainstream it is, but some Sandisk drives use the platter as a "capacitor" to generate enough power to run the park head mechanism.  The motor driver 'regens' onto the isolated 12V bus to run some of the electronics on the board, and then once the head is parked the final action is to 'brake' the platter to a stop as quickly as possible.  The data in the 64MB cache (if it's partially a write-delay cache) is presumably lost, as there isn't enough time to write that out.  For SSDs, it's common to see an array of capacitors on the drive which are intended to provide enough worst-case runtime to empty the DRAM caches. e.g. https://images.anandtech.com/doci/9258/IMG_2329.jpg
 

Online wraper

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Re: This Janet Jackson BASSLINE breaks laptops
« Reply #46 on: January 11, 2023, 11:10:14 am »
Even more miraculous is devices like the original iPod with 20 ~ 160GB micro hard disks inside them.  These devices can play music while you are cycling and in my limited experience they never dropped out.
No.  Apple's big thing about the IPOD is that their playback cache was stored in ram as .mp3 and that they had an hours worth of it which was loaded in around ~5 seconds.  If you stopped moving for a few seconds, the drive could power up, load the next hour of music, and go back to deep sleep saving the battery life.
I doubt about hours, classic iPod had 32MB of RAM, later increased to 64MB in 5-6th gen. This is certainly not enough for hours of cache in acceptable quality.
 

Offline ebastler

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Re: This Janet Jackson BASSLINE breaks laptops
« Reply #47 on: January 11, 2023, 01:04:24 pm »
20 minutes of buffering time is what they claimed (and achieved) for the early iPods.
 
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Offline tooki

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Re: This Janet Jackson BASSLINE breaks laptops
« Reply #48 on: January 11, 2023, 06:32:22 pm »
Not sure how mainstream it is, but some Sandisk drives use the platter as a "capacitor" to generate enough power to run the park head mechanism.  The motor driver 'regens' onto the isolated 12V bus to run some of the electronics on the board, and then once the head is parked the final action is to 'brake' the platter to a stop as quickly as possible.  The data in the 64MB cache (if it's partially a write-delay cache) is presumably lost, as there isn't enough time to write that out.  For SSDs, it's common to see an array of capacitors on the drive which are intended to provide enough worst-case runtime to empty the DRAM caches. e.g. https://images.anandtech.com/doci/9258/IMG_2329.jpg
SanDisk doesn’t manufacture hard disks. They may at some point have sold external hard drives (though I couldn’t find any examples), but the actual hard disk drives inside would have been bought from someone else.

Anyhow, it’s my understanding that hard disks do in fact use the motor as a generator to attempt to write our final data from cache when power is lost, but I can’t remember where I read that. I did find a Seagate patent describing using the motor as a generator to then copy the cache to a non-volatile cache (flash?).

They definitely use the energy to park the heads, as you said.
 

Online tom66

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Re: This Janet Jackson BASSLINE breaks laptops
« Reply #49 on: January 11, 2023, 07:02:50 pm »
Not sure how mainstream it is, but some Sandisk drives use the platter as a "capacitor" to generate enough power to run the park head mechanism.  The motor driver 'regens' onto the isolated 12V bus to run some of the electronics on the board, and then once the head is parked the final action is to 'brake' the platter to a stop as quickly as possible.  The data in the 64MB cache (if it's partially a write-delay cache) is presumably lost, as there isn't enough time to write that out.  For SSDs, it's common to see an array of capacitors on the drive which are intended to provide enough worst-case runtime to empty the DRAM caches. e.g. https://images.anandtech.com/doci/9258/IMG_2329.jpg
SanDisk doesn’t manufacture hard disks. They may at some point have sold external hard drives (though I couldn’t find any examples), but the actual hard disk drives inside would have been bought from someone else.

Anyhow, it’s my understanding that hard disks do in fact use the motor as a generator to attempt to write our final data from cache when power is lost, but I can’t remember where I read that. I did find a Seagate patent describing using the motor as a generator to then copy the cache to a non-volatile cache (flash?).

They definitely use the energy to park the heads, as you said.

Sorry, getting my Sandisk and Seagate mixed up - I do mean Seagate. 

I think the problem with flushing the DRAM is that it's likely going to be many sectors across the disk, and if it requires more than a few seeks, you'll deplete the energy in that disk pretty quickly.  Also, now you need the controller itself to be running, which normally operates from a little regulator hanging off the 5V rail, and the controller needs to be able to manage with a varying disk speed rather than a fixed one, which probably creates all sorts of complications for managing the DSP stuff.

Not impossible to imagine they could flush something like a bad sectors table, or flush RAM to flash.  The latter would be an almost entirely deterministic operation.   Maybe they could dump the DRAM linearly to the start of the disk in a reserved sector range? It'd need to recover this sector on the next power on, but might work.
« Last Edit: January 11, 2023, 07:04:40 pm by tom66 »
 


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