USB for charging and data connection: a threat?

[debernardis]

Please talk me down on that:
say I get my n900, I'm happily roaming in the wild world, and I get at the office of a coworker or at a friend's home... and I need some charging of my precious...

Well I open my (geek?) bag, take the usb cradle and plug to his/her computer...

and - here starts my nightmare - my flash drives are mounted by his/her machine, and
1) vfat partitions get flooded by virii, files get encrypted by some obscure fellow who wants money by western union to send me a maybe password;
2) a trojan rsyncs everything and my personal documents are sold by mafia to the best bidder;
3) everything is thrashed, erased, and my precious blows away like any trivial iphone...

Now, am I paranoid? Can I avoid automounting? Should I bring the mains charger everywhere and avoid usb ports of computers as hell?

Thanks :eek:

[ossipena]

buy another usb-cable and cut data wires from it?

[linuxeventually]

No. You need the data connections, unfortunately. Nokia has this bad habit of requiring data to be sent while charging (should be an optional feature). Someone might create something similar to the USB OTG applet to manually override automounting. You might also consider something like the Lenmar powerpack mini. Plug the N900 into the tiny lithium battery and then a cable from that to the computer. That or pack a USB=>AC adapter.

I'm sure something will be created to avoid this problem. The reason it doesn't exist for the N8X0 is that one cannot charge via USB (from the mini/micro-usb port; 1mm=>usb cables work) but with the N900 the problem will present itself and someone will provide a fix (assuming Nokia doesn't).

[ysss]

http://qlstore.com/images/Usb.JPG

they're small

[Stskeeps]

I wouldn't worry about this. Released ke-recv sources reveal that there's probably an interactive selection of mode. That means, no mass storage provided unless explictly told to.

[tz1]

On the existing tablets, keeping an open file on a volume prevents it from being exported to be mounted (to my frequent irritation).

Plugging it in causes it to do a umount, which can fail. It would be easy to create an applet to prevent it.

[Lord Raiden]

http://qlstore.com/images/Usb.JPG

they're small
Yeah, I was going to suggest exactly something like that. debernardis, use a usb charging brick like what ysss suggested. If you can't use a brick, then get a portable battery powered battery charger. We talked a lot about them in this thread here (http://talk.maemo.org/showthread.php?t=22610&highlight=battery+powered+charger). I personally have the mp1550 and love it. :)

[zerojay]

Please talk me down on that:
say I get my n900, I'm happily roaming in the wild world, and I get at the office of a coworker or at a friend's home... and I need some charging of my precious...

Well I open my (geek?) bag, take the usb cradle and plug to his/her computer...

and - here starts my nightmare - my flash drives are mounted by his/her machine, and
1) vfat partitions get flooded by virii, files get encrypted by some obscure fellow who wants money by western union to send me a maybe password;
2) a trojan rsyncs everything and my personal documents are sold by mafia to the best bidder;
3) everything is thrashed, erased, and my precious blows away like any trivial iphone...

Now, am I paranoid? Can I avoid automounting? Should I bring the mains charger everywhere and avoid usb ports of computers as hell?

Thanks :eek:

I heard there are special pills that can help.

[debernardis]

Thanks all... I know, I have one of those bricks, and one for my car but... a usb cable is much smaller especially a retractable one.

@Linuxeventually, what happens if you cut the data wires? Does it mean that the mains charger has those data wires connected in order to charge devices like the n900?

[qgil]

no mass storage provided unless explictly told to.

^^^^^^^^^^^^

[ysss]

You can't get any smaller than this... and it's only $5 each. Multi voltage to boot:

http://www.made-in-china.com/image/2f0j00ceAEyIMdrfuDM/USB-Charger-for-iPhone-3G-BL-70707-.jpg

[nilchak]

I just saw in this video that there is an Charging adapter cable (at 1:35 mins) included in the retail box (as shown in this unboxing video (http://www.youtube.com/user/stevechippy#p/u/3/2nzkccfl4Y0) from the Maemo summit).

With this I guess we can reuse the old Nokia wall chargers for the N810 or any N series phones and convert that to a USB charger for the N900. Pretty sweet.

And this means you obviate the issue of connecting to a computer and can use your existing wall chargers.
I do hope this is included in all retail boxes.

[zerojay]

You can't get any smaller than this... and it's only $5 each. Multi voltage to boot:

http://www.made-in-china.com/image/2f0j00ceAEyIMdrfuDM/USB-Charger-for-iPhone-3G-BL-70707-.jpg

They will not work. Nor will any other USB to wall charger. Your N900 must be plugged into something that actually USES USB.

[biggzy]

I just saw in this video that there is an Charging adapter cable (at 1:35 mins) included in the retail box (as shown in this unboxing video (http://www.youtube.com/user/stevechippy#p/u/3/2nzkccfl4Y0) from the Maemo summit).

With this I guess we can reuse the old Nokia wall chargers for the N810 or any N series phones and convert that to a USB charger for the N900. Pretty sweet.

And this means you obviate the issue of connecting to a computer and can use your existing wall chargers.
I do hope this is included in all retail boxes.

yes the n97 also came with the adapter but i would recommend not using it, why you ask? take a look ... http://www.dani2xll.com/my_weblog/2009/08/nokia-n97-adapter-meltdown.html

[biggzy]

They will not work. Nor will any other USB to wall charger. Your N900 must be plugged into something that actually USES USB.

why not? they work with the n97, i cant see the n900 charger port being any dif.

[nilchak]

They will not work. Nor will any other USB to wall charger. Your N900 must be plugged into something that actually USES USB.

Then why is this Charger cable adapter (Wall to USB) included in the retail N900 boxes - see unboxing video at 1:34 mins (http://www.youtube.com/user/stevechippy#p/u/3/2nzkccfl4Y0).

I understand from the brief video that this is so that you can reuse the existing (or any new) wall chargers to charge the N900 thru this USB adapter cable.

[Thesandlord]

They will not work. Nor will any other USB to wall charger. Your N900 must be plugged into something that actually USES USB.

Why? iPods, Cameras, Other devices all charge via wall changers. If I can't charge the N900 with a wall charger, not buying... The whole point is to NOT have to lug around a laptop...

[biggzy]

dont worry guys, it will charge via wall etc just like n85/n86/n97 etc

[NvyUs]

you will get 3 options from the box to use to charge the n900.

1.charger
2.USB lead
3.a USB charger adapter to connect to the end of any old chargers you may have

[zerojay]

Why? iPods, Cameras, Other devices all charge via wall changers. If I can't charge the N900 with a wall charger, not buying... The whole point is to NOT have to lug around a laptop...

All I can tell you is that I have three wall chargers and not a single one of them works with my N900. I didn't get a retail box, so this adapter that others have mentioned... I didn't know about.

[Hogwash]

I don't see any reason why another charger - same voltage, with USB adapter - shouldn't work. The power line is all that is being used, not the data lines.

[shadowjk]

The issue is that from USB you are not allowed to draw more than 100mA without negotiating with the host first, asking permission to draw full 500mA. If the host computer give permission for this, the device can then start consuming more power.
For "dumb" chargers, I believe they added a way to signal to the device, that the other end is a charger, by shorting the data lines together. In that case the device can pull as much power as it can get.

There's probably a million metric tonnes of chargers and devices manufactured before USB Charging was standardized. They are not USB Compliant, and might or might not work, might fry your computer's USB port, etc...

[ossipena]

You can't get any smaller than this... and it's only $5 each. Multi voltage to boot:

http://www.made-in-china.com/image/2f0j00ceAEyIMdrfuDM/USB-Charger-for-iPhone-3G-BL-70707-.jpg

Actually you can. I have couple of smaller ones i think. Shape is exactly same as the smallest nokia wall chargers plug (comes with e71) so it is probably same size but thinner..

e: and price was $2 or $3.

[ysss]

@ossipena: the smallest nokia wall charger is at least about 1.5x larger than that.

[jodyfanning]

@ossipena: the smallest nokia wall charger is at least about 1.5x larger than that.

Are you sure about that...

http://europe.nokia.com/find-products/accessories/all-accessories/power/chargers/nokia-charger-ac-5

[ysss]

I'll take a picture of them side by side later..

[Helmuth]

I've bought this one for my N95 and could also use it with the N900 (i hope):


http://www.powerguy.de/images/products/SPX.1100_ani_s.jpg
(http://www.powerguy.de/index.php?p=products&area=1&action=showproduct&id=12&name=powerguy-spx-1000/)
Power Guy SPX.1100 (http://www.powerguy.de/index.php?p=products&area=1&action=showproduct&id=12&name=powerguy-spx-1000/)

You have your extra Power with you, you can load it over USB and during charging the Powerguy you can Charge also your Mobile. Expensive but great!

[bandora]

Well as far as I know.. this won't happen at all... Since on my N97 when I connect the microUSB onto any computer it will instantly start charging.. and then it will ask you what type of connection do you want it to connect (PC Suite, Data, or media).. But if you leave it on that screen or press cancel it won't do anything except charge the phone.. so I expect the N900 to do the same exact thing..

[pycage]

I don't see any reason why another charger - same voltage, with USB adapter - shouldn't work. The power line is all that is being used, not the data lines.

It seems to be a firmware issue. With OS 37.x I was able to charge from a USB car adaptor, since OS 39.x it doesn't want to charge anymore.

[ysss]

Are you sure about that...

http://europe.nokia.com/find-products/accessories/all-accessories/power/chargers/nokia-charger-ac-5

Check it out..

http://i34.tinypic.com/ibjhva.jpg

[sjgadsby]

All I can tell you is that I have three wall chargers and not a single one of them works with my N900.

For completeness, using a CA-100 charger (http://www.nokiausa.com/find-products/accessories/all-accessories/memory-cards-and-cables/cables/nokia-cable-ca-100) plus the CA-146C charger adapter (http://www.nokia.co.uk/find-products/accessories/all-accessories/power/charger-adapters/nokia-charger-adapter-ca-146c) to convert from simple USB power to Nokia 2mm and back also doesn't work. It, uh, seemed like something to try.

I know one person at the Summit had a homemade, hacked & taped, USB cable that did allow the N900 to charge from simple USB power sources. He said he had cut the data lines. I'll leave it to him to volunteer more information should he be so inclined.

[shadowjk]

aw, I actually expected ca-100 - ca-146 chain would work

[daperl]

The data lines are important. Read section "3.2 Charger Detection Hardware" of the "Battery Charging Specification (http://www.usb.org/developers/devclass_docs/batt_charging_1_1.zip)" [zip file]. This is probably a copyright violation, but here's a pretty picture:

4324

[Texrat]

All I can tell you is that I have three wall chargers and not a single one of them works with my N900. I didn't get a retail box, so this adapter that others have mentioned... I didn't know about.

A straight USB to micro USB cable from laptop to N900 isn't working, either.

EDIT: I take that back-- it works intermittently.

*sigh*

EDIT 2: more detail...

The first 2 times I plugged the straight USB-to-micro-USB cable into both devices, nothing happened. Third time (being the charm) I received a dialog that said "Current state: charging only" with the options to override by selecting "Mass storage mode" or "PC Suite mode". Sweet. That is what I would expect.

[jodyfanning]

Check it out..

http://i34.tinypic.com/ibjhva.jpg

Thats tiny. If you look closely at the picture I think they couldn't even have a European plug version as there isn't enough room to separate the pins!

[zerojay]

So... I leave for a trip in two weeks where I won't have access to a laptop. I never received this USB power adapter... what do I do?

I think it was qole that probably hacked the USB cable. Doubt I'd be able to do it myself.

[twoboxen]

So... I leave for a trip in two weeks where I won't have access to a laptop. I never received this USB power adapter... what do I do?

I think it was qole that probably hacked the USB cable. Doubt I'd be able to do it myself.

easy as pie... there are 4 wires in usb. +5V, Ground, Data+, Data-. You just have to cut at least one of the data wires, but I'd just cut both.

[zerojay]

easy as pie... there are 4 wires in usb. +5V, Ground, Data+, Data-. You just have to cut at least one of the data wires, but I'd just cut both.

Okay, and those are... what color?

[ysss]

Thats tiny. If you look closely at the picture I think they couldn't even have a European plug version as there isn't enough room to separate the pins!

You are right. That's just the US version, Apple makes a bigger but modular USB adapter design for the rest of the world.

[sjgadsby]

All I can tell you is that I have three wall chargers and not a single one of them works with my N900.

USB power adapter that works with the N900, no modifications required: http://www.dealextreme.com/details.dx/sku.25

At least, the one I purchased two years ago does.