Hack to boot pandora without battery. Is it possible?


asimov-solensan

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Well now that a successor of the pandora is more than a rumor, and hearing ED's intentions for it I'm sure I'm going to buy it for sure.

But I don't like to store my old devices to gather dust, I love to find a second life for old electronics, and if I can't I prefer to sell them or even gift them if know someone that find it useful.

Certainly the pandora as a full fledged PC can have it's place in my home. My intention is to leave it attached 24/7 to a TV and use it to load fillms and series from my server, also with a hub and a pair of gamepads it will be a superb console. Me and my brother in law only need mame+windjammers to waste an enire day in front of the TV.

Or even use it as my server for samba, sshfs, cups, bittorrent, etc ... Now I use an old VIA epia (from 1999) for this task.

Any of the two cases will mean leave the Padora all day connected and I fear for the battery. I don' want to set my home on fire, and besides, battery is not needed for this matter I can use it as a spare battery for P2.

Therefor I was thinking if any kind of circuit culd made that connected to the battery pads could trick the board to think that there is a battery and boot the system as usally.
 
One potential hack you could do is to use the large - and + pads available on the pandora's mainboard for power supply.

IIRC they were designed to be used for bench test, so don't need any battery plugged.
 
Therefor I was thinking if any kind of circuit culd made that connected to the battery pads could trick the board to think that there is a battery and boot the system as usally.
Afaik some (most?) Pandoras should run without a battery out of the box - have you already tried it with yours ?
 
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Therefor I was thinking if any kind of circuit culd made that connected to the battery pads could trick the board to think that there is a battery and boot the system as usally.
Afaik some (most?) Pandoras should run without a battery out of the box - have you already tried it with yours ?
is thie true?i seem to remember the power is not enough once you go past the boot command line.
 
There is enough of everything, it's just TI declaring it's power chips are not guaranteed to support such mode of operation. All my pandoras can do it at least..
 
My 2 pandas (Rebirth+1ghz) works great even without the battery inserted
 
My Rebirth worked without battery, the new 1 GHz board I upgraded to does not.

Would be nice to have the option ... would it be possible to just short-circuit the contacts in the battery-compartment or something like that? Probably not ...
 
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I know, but I was hoping for a way that allows me to use the connector that's already there. Would be a lot more elegant compared to having an additional connector hanging out of a hole in the Pandora on some wires <_<
 
Just put the connector in the battery compartment, get another battery cover and drill a hole into it ;)

Ingoreis (I hope I didn't spelt his nick wrong) added a Wifi antenna connector on the back of the pandora, maybe something similar could be done to add a small power connector…
 
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I still wouldn't call this an elegant solution, but it's probably what I'm going to do when my battery dies and there are no more replacements because the Pandora 5 finally uses a different battery-design :D
 
I was planning on going fallout-style with car batteries :D
 
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Therefor I was thinking if any kind of circuit culd made that connected to the battery pads could trick the board to think that there is a battery and boot the system as usally.
Afaik some (most?) Pandoras should run without a battery out of the box - have you already tried it with yours ?
is thie true?i seem to remember the power is not enough once you go past the boot command line.
It's true, otherwise charging the battery wouldn't work. From what I understand you might not see any visible sign of it being on if the battery discharges past a certain point, but you certainly can run the Pandy without a battery installed.
 
I should mention this:

Never insert or remove the battery while your pandora is connected to the mains. This can confuse the charge-controller, potentially frying your pandora's guts!

(edit: see technical details below)
 
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It's true, otherwise charging the battery wouldn't work. From what I understand you might not see any visible sign of it being on if the battery discharges past a certain point, but you certainly can run the Pandy without a battery installed
These are actually two different things. When there's a battery in the Pandora and you plug it in, the charge chip feeds power into the battery and the Pandora simultaneously runs off the battery: that's why the battery needs to be pre-charged to a minimum voltage before it turns on.When you remove the battery and plug it in, the TWL goes into a constant voltage mode, where it feeds 4.2v directly to the Pandora. When you insert a battery the TWL detects that and switches to regular charge mode, but for a very brief moment there's the 4.2v from the charger and 4.2(ish) volts from the battery: massive overvoltage and you risk blowing out the Pandora.

The reverse is also true: when you remove the battery the TWL detects that and goes back to constant voltage, but unfortunately for a very brief moment there is no power from either so the OMAP resets.

If the TWL refuses to go into constant voltage mode (ie, powered off the mains without a battery) then applying a constant 5v to the battery contacts is perfectly fine as long as several conditions are followed

1) Never, ever, EVER plug it in through the connector or USB, as this will attempt to charge the constant voltage you're feeding it and that will not end well at all.

1a) I'm pretty sure there's actually a way to disable the TWL charging entirely and if it comes time I would gladly do a hack on the driver for you just so that it never accidentally gets plugged in and turned on. You may want to use that mini-USB connection, after all.

2) It will think it is drawing power from a battery, and that battery will eventually be dead. You need to change the settings so that it doesn't do anything when the percentage drops to 0.

3) Wire a thermistor (or really any suitable resistor) between the power and middle pin of the connection so it doesn't think your battery is overheating. I'm not sure what resistor is required but we could figure it out if you needed to. I'd stick with a thermistor though, just because that's another feature you can abuse, turn your Pandora into a thermostat :p
 
Thanks a lot for the answers. Seems that easier solution will be to just plug the power source to the battery connections and pass a cable through the case.

I never used the mini-usb for charging the Pandora and I don't see how I would connect the power port unintentionally.

Still for security issues it would be interesting to have a script which disables the charging system.
 
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