Don't Use Lacie 2.5" Usb Hard Disk Drives With A Pandora

[MWeston]

Plugging a LaCie Rikiki 2.5" USB 2.0 HDD into my Pandora not only did not work, but it resulted in a frightening display of the screen pulsating wildly - it looks like these drives try to draw way too much power. It looked almost the same as what happens when you place a speaker (or a magnet) too close to an old CRT monitor.

Was your battery fairly low at the time? It's one of those things that should go on the Wiki although it has been mentioned many times that 2.5" drives and larger won't work anyway (for the most part since most if not all vendors ignore the USB spec). If you really want to jam as much power as possible (up to the 750mA peaks) out of the host port, it's something that should be done with a battery that has most of its charge. It's best to have a cell voltage of at least 3.8V (50%-ish?) to pull that much current. Of course that is based on the datasheet and actual results may vary. Since the USB protection circuit disconnects the load and then auto-retries to reconnect, this could result is some higher spikes above 750mA which is likely the pretty effect you saw on the LCD. There is a signal connected to a GPIO on the OMAP chip that reports an over current condition but as far as I know, it is unmonitored. Ideally, this could be used to put a better delay in before attempting to re-power the USB port which would diminish the transients.

 

[Prometheus]

Was your battery fairly low at the time?

Nope - it was either 96% or 98% when I tried this, if memory serves.

It's one of those things that should go on the Wiki although it has been mentioned many times that 2.5" drives and larger won't work anyway (for the most part since most if not all vendors ignore the USB spec).

True. I was just trying it as a "Because I can" sort of thing, really (and to add stuff to the USB Compatibility List). :lol:

That said, Western Digital's 2.5" 160GB "Elements" HDD does work, incidentally (and with my battery at around 54%, at that) - I tried that one earlier. I guess WD don't ignore the specifications. (For what it's worth, I have three USB HDDs, the third being a Toshiba one. I don't know where it's wandered off to, but when it turns up I'll give that one a try, too)

Since the USB protection circuit disconnects the load and then auto-retries to reconnect, this could result is some higher spikes above 750mA which is likely the pretty effect you saw on the LCD.

I'm not the most technical of people, but that's what I thought it was, to be honest. It seemed like a common-sense answer. I'm not too sure that I'd describe it as pretty, though - pretty terrifying, maybe! :lol:

 

[wejp]

Plugging a LaCie Rikiki 2.5" USB 2.0 HDD into my Pandora not only did not work, but it resulted in a frightening display of the screen pulsating wildly - it looks like these drives try to draw way too much power. It looked almost the same as what happens when you place a speaker (or a magnet) too close to an old CRT monitor.

Was your battery fairly low at the time? It's one of those things that should go on the Wiki although it has been mentioned many times that 2.5" drives and larger won't work anyway (for the most part since most if not all vendors ignore the USB spec). If you really want to jam as much power as possible (up to the 750mA peaks) out of the host port, it's something that should be done with a battery that has most of its charge. It's best to have a cell voltage of at least 3.8V (50%-ish?) to pull that much current. Of course that is based on the datasheet and actual results may vary. Since the USB protection circuit disconnects the load and then auto-retries to reconnect, this could result is some higher spikes above 750mA which is likely the pretty effect you saw on the LCD. There is a signal connected to a GPIO on the OMAP chip that reports an over current condition but as far as I know, it is unmonitored. Ideally, this could be used to put a better delay in before attempting to re-power the USB port which would diminish the transients.

I am experiencing the same pulsating screen phenomenon when connecting USB devices, but I am sure that this can't be caused by a too high current being drawn from the USB port in my case. The device I was using was s simple USB mouse connected through a USB 2.0 hub. The mouse is rated with 20 mA which is way below the maximum 500 mA a USB port should be able to handle. I also tried with another mouse and other USB devices with the same result. Also, it does not matter if the battery is fully charged.
The pulsating screen looks like it could be caused a wrong grounding (e.g. no proper no star grounding) inside the device or something like that.

 

[TitanUranus]

I am experiencing the same pulsating screen phenomenon when connecting USB devices, but I am sure that this can't be caused by a too high current being drawn from the USB port in my case. The device I was using was s simple USB mouse connected through a USB 2.0 hub. The mouse is rated with 20 mA which is way below the maximum 500 mA a USB port should be able to handle. I also tried with another mouse and other USB devices with the same result. Also, it does not matter if the battery is fully charged.
The pulsating screen looks like it could be caused a wrong grounding (e.g. no proper no star grounding) inside the device or something like that.

It's possible your USB device is acting like a bit of an aerial and getting some unwanted interference. I suppose you could try the same idea I used when I suffered a similar problem - wrap the device and cable in aluminium foil. I was going to use the word "tinfoil" but you don't see tinfoil anywhere these days. When I was a kid you really did get tinfoil, and I remember it used to go rusty as well.

EDIT: I messed up that quote - what a fiddley pain in the anus it was to put it right.

 

[paddy]

Sounds like cheap chinese hardware to me,ill need to plug in all my usb crap now as i want to see the light.

Only kidding btw but thinking about things,how safe is the pandora ? the battery is totaly custom made and doesn't have any protection so what is the worst that could happen when charging or even just using the unit not plugged into mains.


i have tin foil in my house,just buy it every other week in supermarkets like asda,tesco and everywhere,i like to make hats.

 

[Prometheus]

Sounds like cheap chinese hardware to me,ill need to plug in all my usb crap now as i want to see the light.

Only kidding btw

And here was me ready with a jokey comeback about how the thing's not made in China. :lol: (Seriously, though, apparently the LaCie one is made in Taiwan, and the Western Digital is manufactured and assembled in Thailand, if anyone's curious. I have no idea about the Toshiba, as I haven't looked for it yet. )

Speaking of light, I must try out that USB lamp of mine. Thanks for the reminder. :lol:

but thinking about things,how safe is the pandora ? the battery is totaly custom made and doesn't have any protection so what is the worst that could happen when charging or even just using the unit not plugged into mains.

I'm pretty sure that the battery does have protection - I've yet to come across a lithium-based rechargeable that doesn't. That said, I'm also mildly curious as to what the worst case scenario would be for a Pandora that's faced with problematic USB hardware like the LaCie drive.

 

[TitanUranus]

i have tin foil in my house,just buy it every other week in supermarkets like asda,tesco and everywhere,i like to make hats.

And how much ham is in a hamburger? Just 'cause it's labeled tinfoil doesn't mean it's tin - it's aluminium. If it's real tinfoil (like the kind in the olden days...) you can cut tiny pieces off and move them with a magnet under the table.

 

[hedwards]

it says its for windows but it still works on pandora which is linux?

You have to be mindful of that. I've got a passport external drive, the 160gb, I think, and it works well until it goes into it's proprietary powersave mode. At which point, nothing but the claimed compatible OSes is going to wake it up without disconnecting it or rebooting it.

 

[grahamr]

And here was me ready with a jokey comeback about how the thing's not made in China. :lol: (Seriously, though, apparently the LaCie one is made in Taiwan, ...

In the spirit of splitting inconsequential hairs unrelated to the actual discussion (the lifeblood of this forum). I'd just like to point out that Taiwan *is* china. Just, umm, a different china kinda like how north and south korea are both still korea.

 

[second exodous]

Pre-assembled 2.5 external drives are pretty annoying in my opinion because exact same model numbers they have different SATA to USB bridge boards inside even tough the drive itself stays the same. I have gotten the exact same drive twice and noticed one was slower than the other, popped them open and it had the exact same drive but had different boards in them.

LaCie might be more reliable than WD. The WD drives themselves are great, all my notebook drives are WD, but their external cases don't always use the same board inside. I've stopped buying pre-assembled external 2.5 drives and just but a OEM drive and an external enclosure that I can switch drives out. I also like to have eSATA because it faster and the best way to get that on a external drive is to but an empty case that has one.

Anyway, making a list of compatible external drives might not be 100% reliable since the bridge boards on the inside might differ.

 

[fanoush]

It is rated at 2W active and 0.5W stand by. So, in theory the Pandora would be able to supply stand by power to it - but that isn't going to get it far.

well, 500mA at 5V is 5*0.5=2.5W so 2W should be fine

 

[paddy]

i have tin foil in my house,just buy it every other week in supermarkets like asda,tesco and everywhere,i like to make hats.

And how much ham is in a hamburger? Just 'cause it's labeled tinfoil doesn't mean it's tin - it's aluminium. If it's real tinfoil (like the kind in the olden days...) you can cut tiny pieces off and move them with a magnet under the table.

i read that with an old wild west accent in mind

I see what you are saying tho ,and that is true my friend.

 

[hedwards]

And here was me ready with a jokey comeback about how the thing's not made in China. :lol: (Seriously, though, apparently the LaCie one is made in Taiwan, ...

In the spirit of splitting inconsequential hairs unrelated to the actual discussion (the lifeblood of this forum). I'd just like to point out that Taiwan *is* china. Just, umm, a different china kinda like how north and south korea are both still korea.

Umm, no Taiwan isn't China, and North and South Korea aren't both Korea in any meaningful way. The Chinese government doesn't recognized Taiwanese sovereignty, but they have their own independent government, military, tax system etc., and do get their own weapons from the US, that's hardly indicative of being a part of China. North and South Korea are still technically at war as they've never signed anything to formally end the Korean war that's been technically ongoing since the 50s. Like Taiwan, both have their own independent systems of governance, weapons, taxes etc.

I'm not sure on what basis you'd suggest that they're one in both cases.[/end threadjack]

 

[God Ginrai]

LaCie might be more reliable than WD.

Wait wait wait... You're saying that something that caused flickery death on the OP's screen is more reliable than something that worked without a hitch?

I'm not sure on what basis you'd suggest that they're one in both cases.[/end threadjack]

I'm pretty sure he is referring to the fact that China is called "People's Republic of China" and Taiwan is called "Republic of China". http://en.wikipedia.org/wiki/Republic_of_China

-God Ginrai

 

[second exodous]

LaCie might be more reliable than WD.

Wait wait wait... You're saying that something that caused flickery death on the OP's screen is more reliable than something that worked without a hitch?

Did you not READ my post? I meant LaCie might be more reliable for like models having the same bridge boards. WD is not, if you read my post you would know that when I opened two of the same WD models that they had different bridge boards and there for had different speeds when plugged into the computer. READ THE ENTIRE POST!

I'm just saying that a list of comparable external drives might not be 100% accurate since in my experience, at least with WD, they use different bridge boards in the same model number. LaCie might use the same bridge board in like models making it more reliable. Nothing to do with compatibility with the Pandora!

The hard drive in the casing doesn't not determine the compatibility, nor does the casing itself, but the bridge board that hooks into the SATA connectors of the hard drive and allows the computer to plug into it through USB. Do you understand what a bridge board is and what I'm trying to say?

 

[kloplop321]

I would love to see a video of this
Though I take no responsibility if something BAD happens

 

[God Ginrai]

LaCie might be more reliable than WD.

Wait wait wait... You're saying that something that caused flickery death on the OP's screen is more reliable than something that worked without a hitch?

Did you not READ my post? I meant LaCie might be more reliable for like models having the same bridge boards. WD is not, if you read my post you would know that when I opened two of the same WD models that they had different bridge boards and there for had different speeds when plugged into the computer. READ THE ENTIRE POST!

I'm just saying that a list of comparable external drives might not be 100% accurate since in my experience, at least with WD, they use different bridge boards in the same model number. LaCie might use the same bridge board in like models making it more reliable. Nothing to do with compatibility with the Pandora!

The hard drive in the casing doesn't not determine the compatibility, nor does the casing itself, but the bridge board that hooks into the SATA connectors of the hard drive and allows the computer to plug into it through USB. Do you understand what a bridge board is and what I'm trying to say?

I did read your post. And I assumed that you were saying that because the WD used different bridge boards for the same models that they were less reliable for use with the Pandora.

I don't understand why you would compare two models of hard drives for reliability when you aren't even comparing them for reliability for use with the system being discussed.

-God Ginrai

 

[second exodous]

^ Yes, but what I am saying is one of my WD drives might work and one might now because even though they are the same model number they use different hardware. So if one works and one doesn't what do I put on the list? I have two of the same model number and only one works? How does this help anyone? That is all I'm trying to say.

So I have two WD3200MLBP-00 drives that have different hardware inside so they have different speeds on my PC so they might act differently on the Pandora. When I get mine I'll try them both out to see what happens. Actually the slow one I took apart to use the drive in my computer but I have the bridge board and see what happens. They both might work, I don't know, but I only have two, maybe there is a third or even a fourth bridge board WD uses in the same model, highly unreliable to put on a list as working or not even if both of mine work.

I don't have my Pandora yet but do you see why I would be hesitant to trust a list of external hard drives when I know this? I say get what is cheap or the size you want, try it, if it doesn't work try again. I'd just get a bare enclosure and get the drive you want, if it doesn't work you're only out $20 or $30 but you still have the drive to try in another enclosure.

 

[hobbyman II]

that's a good point, is there any variation in the serial numbers that would tell you what version bridge board is inside?, otherwise, like you say, it is going to hard to recommend a drive as working if only SOME versions of the same drive do work correctly, this may also be the case with other makers drives, it could be that other people have no problems getting the 2.5" Lacie to work with Pandora for example, maybe the drive that started this thread was an early model, and they revised it later to use less power, needs looking into more imo.

 

[second exodous]

^ My two have the exact same part number but are different inside. The have the exact same drive and the exact same plastic case the bridge board is just different. The bridge board is the only important part as far as compatibility goes, drives will work no matter what.

WD drives them selves are great, noting against the drive itself, it is just the bridge board that worries me.