CMOS backup? -PSP's strange built-in battery

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konfig
Posts: 68
Joined: Thu Jan 06, 2005 4:01 am

CMOS backup? -PSP's strange built-in battery

Post by konfig »

PSP's circuit board. To the right, I think there is a battery.

Image

What is it for? I ever believed that it was for something like CMOS backup on PC - including time function.

But the fact is, whenever you uninstall the PSP's main battery pack(for power supply), you will get a time setting prompt the next time you start your psp(The PSP official guide book also indicated this).

So, seems this small battery has nothing to do with PSP's timing. What could it be for then?
Last edited by konfig on Fri Mar 04, 2005 2:53 am, edited 1 time in total.
zigzag
Posts: 129
Joined: Wed Jan 26, 2005 2:11 pm

Post by zigzag »

Actually, I read elsewhere that you can swap batteries while the system is asleep in a game and resume playing once you put in a new battery. No?
Pikoro
Posts: 56
Joined: Thu Jan 13, 2005 9:57 am

Post by Pikoro »

Wrong. I just tried it here.

When you remove the battery when it's in sleep mode (the recharagable removeable batter that is), the system does not come out of sleep mode. It is the same as a hard power off. It will not recover back to your game.

Cheers
Pikoro
http://www.psphacks.net
Guest

Post by Guest »

Thank you for testing this. This is indeed interesting. Please keep up the useful work and keep posting that kind of information here :)
konfig
Posts: 68
Joined: Thu Jan 06, 2005 4:01 am

Post by konfig »

:
"whenever you uninstall the PSP's main battery pack(for power supply), you will get a time setting prompt the next time you start your psp(The PSP official guide book also indicated this). "

I did a test yesterday when the battery power ran out and found something different.

This time, PSP's time did not reset when it got power supply(AC adapter, no battery pack) 2 minutes later - alough time did reset the last time when PSP lost power supply temporarily(that's about a day long).

Also what the PSP official guide book says is "when battery pack is gone, PSP's time sometimes resets"(not always, I did not read the book that carefully before. sorry).

Without external power supply, PSP's time still lasted at least 2 miniutes.
So I'd like to believe it is the contribution of this small battery: it is a rechargeable battery to keep some information(including system time, maybe RAM content as well) for a short while to enable battery pack exchange(though it can't last too long). It charges when PSP is connected with a power supply(battery pack, AC adapter etc), regardless of whether PSP is running.

Hope this can be of some use.
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