Hey guys,

More and more I see people with these sidekicks. And I like it. And I had an idea. When my zaurus is playing mp3s (thus the display is off and the hdd accesses once or twice per song), I notice my battery life is HUGE... 10+ hours... Perfectly adequate for having my zaurus on and idling at all times. Then a buddy of mine told me that when you make a GPRS connection via bluetooth it doesn't really prevent the cell phone from working at all, just that the data stream is interrupted during a call. This is huge for me. This means I can carry my cell phone in one pocket and make a GPRS connection. Now I realized that the USB bluetooth dongle I have probably wouldn't work out so I'd have to carry something like the Belkin CF BT adapter which goes for $2.94 on ebay right now. The more and more I think about this, the more I feel it would work as long as the power subsystem is modified a bit. Basically closing the screen would have to instead of turning the unit off, turn the display off and switch to as low of a low power mode as possible. Probably dumb the system MHz as low as possible. The bluetooth draws next to nothing unlike wifi so the power numbers suggest it could work. And if these sidekicks or treos on their limited battery life can do it, chatting with a CELL TOWER versus just bluetooth, why can't a zaurus?

Thus whenever you open your zaurus, gaim is open, messages are waiting, you can sync up email as you walk and your zaurus will scream whenever it gets something. Is anyone working this way? I totally want to do it Always having internet for my zaurus would TOTALLY complete the experience for me, rather than having to constantly fight with wifi access points. Additionally the bluetooth cf adapters are so cheap, I wouldn't feel obligated to carry it separate from teh zaurus to protect it, so it'd be simple

What do people think?

I have a cellphone bluetoothed to my zaurus. When i run gaim, i run it woth the portrait mode to prevent the zaurus from suspending. I also have my emails downloading when i feel like it. I take long drives in my car and my zaurus is open of course it is closed with pdair pda case for the zaurus from brando.

Gaim does recieve messages and opens up pop up windows but it does not warn me at all. I leave both pda and cellphone blugged into my car cig lighter when i am driving around. but i make sure to plug in devices after car is on to prevent power surges causing damage.

yep....pretty much a side kick in this manner. I also have webaccess anywere and do not need wifi. I have unlimited net access for 24 a month in adition to my phone calls. Digital access is free but voice is not between normal operating hours but it is alot of fun.

the bluetooth is made from taiwan..and needs to be

ambicom bt2000-cf bluetooth-made in taiwan

and i use bluez and configured everything with ease by editing some strings with zeditor.

my cellphone is a siemens s56 with the previous owners of at&t which is now cingular...blah!

let me know if need help...i use gaim exclusively but with msn...icq or aim might need to use another software. and there is but havent tried em yet.

I don't think that Belkin card works with the Zaurus though. From what I can tell, it is actually a little tricky to find a card that is compatible.

instead of the belkin I would choose a socket bt cf card, since it fits perfect inside the cf slot. I have it and it looks very nice.

For your idea to work (which I have also thought about it, but I don't have a data unlimited plan, sigh), i would suggest:

do a script to:
start cf card
connect to network & get info
disconnect network
power down cf card
sleep x minutes

on the other hand, you are supposed to have your cell bluetooth open all the time, thus draining more battery from your phone as well as, depending on the phone model and bluetooth capabilities, it could be a data-security risk.

Just some thougths, waiting for you to post your findings !!

Hmm. I should have waited a bit... I have just paid for a Belkin BT card... it should arrive in 1-2 weeks.

So I will try to do a couple of things to try if it can somehow still work.

Would anyone have some advice about websites, or discussions about how to set up BT on linux ( or on the C3100)?

Thanks to all...

Well I'm realizing that Belkin card doesn't work now so I'm hunting for a socket or ambicom. I would have an unlimited data plan. For the system to be effective for me, I'd really need it to be on and idling, always ready to receive data. I don't know how it could be any more of a data security risk than using hte bluetooth anyway. My cell phone is setup to not pair with any devices unless you tell it it can. The cell phone is a Sony Ericcson - whatever their cheapest model that has a camera in it is. I'm getting it explicitly for GPRS so that I don't wear the battery in the zaurus. That and I can get it for $12 versus $180 for CF GPRS.

Thanks,
Mark

What exactly do you mean when you say it fits perfectly in the slot? How much does it stick out?

This sounds like an interesting idea, something I've had in the back of my mind for a long while except that I was thinking of using WiFi as there's a network everywhere here at uni.



Not at all - i.e. it's the same size as a CF storage card.



Really? What will you be doing with it that you require such fast updates? I would be quite happy to carry out messaging more slowly (like sending emails, etc.), though it you're also wanting to utilise some form of location awareness then you're probably going to want to have the Z switch on more often as your location/context is changing more rapidly.

I'm not sure how to balance this need and that of saving the battery, but a challenge is always good

In any case I can't really see why the Z couldn't switch on every 1 or 2 minutes, connect to the phone and check for messages/email/whatever, then go back to sleep. I suppose that if the phone could also ascertain it's current location it could then decide how long to sleep for depending on what it expects it might find, etc.

I'd be interested to know what the battery life expectations are with the screen turned off, as well as how much of a power drain using BT (or WiFi) would be, and also how long it takes to obtain a connection - as you'll want to balance the number of sleep (and subsequent connection) cycles against the time (read power) wasted being switched on with BT powered up, but not doing anything useful, just negotiating with the phone, etc.


Si

Which leads me further into power managment:

http://pads.east.isi.edu/presentations/mis...o-pm-report.pdf

Interesting to see that the frontlight takes the majority of the power (are backlighte better or worse?

More important (as the screen will be off - actually will the screen truely be off, or will it just be the backlight?), is the power taken up by the idling IR & sound & serial hardware, this will make a difference. Anyone know whether this stuff is powered down in current kernels?

Another thing I was just thinking, randomly as ever; I remember that underclocking the SA1110 machines could only go so far as otherwise the screen became corrupted (as the clocks are linked via a multiplier/divider iirc - the same may or may not be true for the PXA machines). Anyway, this wouldn't be an issue as the screen would be off anyway, I wonder how much of a difference extreme underclocking would make, and how low the processor could be made to go and still be able to perform the email checking, etc.


Si

That sounds great. Is there a "lip" or something to help facilitate removal from the device?

Does anyone know of any wi-fi cards that are like this?

Exactly the same as a CF storage card, so yes, it has a lip.

This is the Socket BT range of cards (I've only seen two models, rev B & E iirc, but I'd assume the rest are the same),


Si

It has been demonstrated that a person can hack bluetooth without your knowledge and without your phone prompting for authorization. I may try to look for an article on it later.

I'm sorry,

In my quick search I was unable to find the article I was thinking about. Here's one about hijacking audio input/output, but they use the fact that most devices have weak pass keys (0000)


http://www.theregister.co.uk/2005/08/02/car_whisperer/

I think you're right that it is theoretically possible to hack into a bluetooth device (I've read similar articles). But given the short range of bluetooth and the fact that a potential hacker would have to know that you're using bluetooth and have his equipment all set to do the hacking, I'm not convinced that it's a major problem.

1) the socket bt cf does fit complete inside the cf slot. I have rev.2.5G, and now works out-of-the-box with new roms. I had a Belkin, but after 2 weeks of compiling, logging, couldn't make it work. That was almost 2 years ago, so YMMV

2) I don't know of any cf wifi card that doesn't stick out of the cf slot. I have a socket low power wifi, with just 1.5-2 cm out of the cf slot, but is very convenient

3) last week, with my poor hacking skills and my zaurus I could download the phonebook of a collegue who had a nokiaXXXX (where XXXX is a known bt-hackable model). Not to mention it was a proof-of-concept and I deleted the file as soon as downloaded. No pairing needed. I own a SE and bt seems to be ok, but you know, I don't feel like having it on all the time. There are known published methods for hacking which would work I think with any phone

4) I'm trying to dismantle an old phone and create a serial-attached module, with its own battery. You can call it poor-man-diy

Okay, couple things here. First of all, Wifi draws a significant amount of power compared to bluetooth. I think the low range bluetooth cards draw something like 17ma and many of the wifi cards IDLE at 250ma, and draw a lot more during send/receive. Needless to say, I get around 4 hours of battery life with wifi enabled, not to mention the wifi card and the zaurus gets particularly hot. Not good for my pocket So, IMHO wifi is no good for always on. Another comment was why the need for always on. The answer is because there is no server component to aim. If I could run a server that would queue my aim messages and then relay them to my zaurus whenever the zaurus signed on to check for messages, the system would be perfect. But for aim to work properly the system must always be on and connected. This is an interesting need though, and I wonder if a protocol plugin for gaim could be made that - well... connects to itself (running on your desktop at home). Of course turning on to check your email once every 1-2 minutes would be fine.

My primary gripe honestly, is how simple GPRS is compared to Wifi. You turn it on, and it's ready to go. wifi, you have to futz around with finding an AP, then hoping it connects right. Then choosing the right AP based on distance, etc. Then there's the question of whether or not the moronic owner who left it unencrypted would be likely to be mad about you using their AP, etc. I always thought Wifi would be a decent solution, and it is for rural areas (astoundingly), but not in the city where every single AP is a pay AP (I refuse).

My main interest is in having an always ready internet connection so if for some reason I feel like looking up directions on mapquest or something, it's a hop skip and a jump kind of thing. And having my zaurus randomly yell at me to let me know it has email or something is cool

Yes I agree with this, it's just another method, but as I said I'm interested by the idea of switching on for a short time, looking for messages, etc. and then switching back to low power mode.



Ah, I see now why you'd need this.

But if your Z is in your pocket, do you/whomever you're talking to expect real-time conversation? I'd be willing to wait for a minute for my messages to be delivered (a bit like chatting with SMS or Email), and then using Gaim when I'm sat down and want to chat in real-time.



Yes that sounds like an interesting idea.



For me it's the other way around - I pay for GPRS, but WiFi access is free (at least at uni where I spend most of the day).



yep.


Si

For the guy who was looking for a gaim plugin which would connect to itself. I know this isn't exactly what you were looking for. However, if you use irssi, and bitlbee (an irc - im gateway). Irssi has a proxy mode that enables what you were looking for. I use irssi for all my messaging needs. and it's fantastic. I've yet to play around with it on the zaurus yet!

However, if you care about seeing smileys as images (custom smileys don't work on gaim anyhoo), filetransfers (use ftp or email ) and seeing buddy pics (there's a patch for that which saves them to your harddrive, works well i find). Then it's likely not for you.

Just trying to help mate.


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