Firmware Question From The Battery Led


Kensupen

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Joined
Jan 19, 2006
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106
Is it possible to change the value for when the battery LED kicks on? I use nimh 2500s and about 1 min after I turn on my GP2X, the low battery LED kicks on, but it'll still work fine for the next 2-3 hours.

The main part of my question is...
Could this be done with a simple hack to update just a part of the firmware, or would I need a whole new firmware to change the value for the LED to turn on?

Another question.
Does that value still get stored in /dev/batt/? I tried running squidge's voltage meter program, but it just locks up.

-Kensupen
 
We don't have the source for the program so it would have to be rewritten.

the value stored in /dev/batt is the adc value the processor is currently reading from the batts.

I've no idea where the "battery limit" value is stored. Knowing GPH, it's hardcoded.
 
On the other hand, it is very easy to control the battery LED, so it shouldn't be too hard to rewrite the program. :)
 
Nope, rechargable batteries run at ~1.4v. When they reach 1.2v, they are flat and need recharging.

(Yes, I'm aware it says 1.2V along the side of the batteries...)

The problem we have is that the period that batteries give up and the gp2x crashes seems to be different on different battery sets (when combined, some batteries may go until 2.2V before giving up, whilst others may give up exactly on 2.4V), so you can't just say "When this battery reaches X volts, put the power light on". It needs to be configurable.
 
Nope, rechargable batteries run at ~1.4v. When they reach 1.2v, they are flat and need recharging.

(Yes, I'm aware it says 1.2V along the side of the batteries...)

The problem we have is that the period that batteries give up and the gp2x crashes seems to be different on different battery sets (when combined, some batteries may go until 2.2V before giving up, whilst others may give up exactly on 2.4V), so you can't just say "When this battery reaches X volts, put the power light on". It needs to be configurable.

There is another option. The light might be hardware controlled. Anyone up for tracing the circuit?
 
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Using 2500mh rechargeables andI have the opposite effect on firmware 2.0

The battery life appears about 30 seconds before giving up the ghost.

So brief I often don't spot it till too late...
 
No, the battery light is definitely not hardware controlled, it didn't come on at all on early firmwares. And I can force it on and off really quite easily in code.
 
And don't even come at all on my '2x. So It'd realy need to be an adjusted value...

paxl13
 
In some early versions of the 2x (not sure about later ones) there was some units which had the led in the wrong place (so you couldn't see it until you opened the case) or the wrong way around (so it never illuminated).
 
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