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- - [HW-FIX] losing time/date on battery swap? Replace bupbat (https://talk.maemo.org/showthread.php?t=90864)

Re: [HW-FIX] losing time/date on battery swap? Replace bupbat

Hi guys

My N900 dont save the time and date anymore after of remove the battery for few seconds adn suppose i need replace the bupbat capacitor coin.

Do you know any store on internet where i would buy it??

I could not find nothing on stock with the info give by @joerg_rw

Re: [HW-FIX] losing time/date on battery swap? Replace bupbat

Quote:

Originally Posted by joerg_rw (Post 1485684)

Anyway BB_CFG register reset default is 0b00000000, for polyacene cap PAS414 (!!!) I suggest setting it to 0b00011111 as soon as possible during boot

For the record, it's `i2cset -f -y 1 0x4b 0x12 0x1f b`.

Re: [HW-FIX] losing time/date on battery swap? Replace bupbat

Looking for a replacement backup battery available today.

Seems to me that there is enough room around the battery to replace it by something slightly bigger.
Did some/one of you replace it recently?
With what?

Finally, after some years experience, li-ion battery or capacitor?

Re: [HW-FIX] losing time/date on battery swap? Replace bupbat

Hah, is there anothner battery? Loosing time and date while removing battery - I thought it as a device character. Are there some other problems if it's dead?

Re: [HW-FIX] losing time/date on battery swap? Replace bupbat

Yes, another battery. You can see it on the first page of the thread.

There aren't any other problems if it is dead. They all seem to die after one or two years.

Re: [HW-FIX] losing time/date on battery swap? Replace bupbat

I guess no answer means nobody knows but just to be sure, I bump this:

Do someone know with what we could, today, replace the backup battery?
Capacitor, li-ion? Bigger size?
thanks

Re: [HW-FIX] losing time/date on battery swap? Replace bupbat

Any battery that has the same voltage?
If you can fit it in there nicely (no stray contacts to other components), I don't see how this could break your machine.

Re: [HW-FIX] losing time/date on battery swap? Replace bupbat

Quote:

Originally Posted by Maemish (Post 1564467)

Hah, is there anothner battery? Loosing time and date while removing battery - I thought it as a device character. Are there some other problems if it's dead?

Yes, there is a small battery, about 3 mm across and 1 mm high, as a backup for the system timer while you are replacing the main battery (or the main battery is dead). It is supposedly rechargeable but it is never recharged (rumours are that an updated kernel enables the recharging but this did not happen in my experience), so it eventually dies after a few years.

The only negative effect is that, if you let your main battery discharge (or take it out), then the first thing the phone does the next time you switch it on is ask you to enter the current date and time.

Quote:

Originally Posted by ric9K (Post 1564563)

Do someone know with what we could, today, replace the backup battery?
Capacitor, li-ion? Bigger size?

I have been wondering about that too. Particularly the capacitor idea, but the lack of recharging put me off that. Another battery might help, as nonsuch says, but it seemed too much hassle to me to bother.

Re: [HW-FIX] losing time/date on battery swap? Replace bupbat

Quote:

Originally Posted by pichlo (Post 1564581)

Sure, lot for few. Especially if the battery is not recharged. I thought there was a way to enable the charging by sending some bits somewhere (sorry) with I2C-something. Gotta find and try that. (unless you are sure it doesn't work).
EDIT: oops, instruction in post 33, just above.

On the orher hand, I often remove the battery and am a bit bored to

Code:

ntpd -s

each time.