gigabeat F battery indicator is inaccurate.

[Soaa-]

I have Rockbox running on my gigabeat F20.  I've been following the development of this port since markun's first post on MyGigabeat.  Truly wonderful how his worked out!

Problem: The battery indicator is off, in a rather dangerous way.  See, it indicates 0 when there's plenty of power left.  I remember it playing for at least an hour after it indicated 0.  Then I turned it off, and tried turning it back on.  The BIOS had no problem booting, it didn't show the usual "RECHARGE BATTERY" screen.  Rockbox refused to continue playing though, it shut down the player.  That's the first problem, it indicates empty too soon.

The second problem is that it doesn't shut down when it indicates empty.  That can be dangerous to the player as it can run totally dry, unless the BIOS kicks in and forces a shutdown.

[Llorean]

The hardware itself will cut off the battery before it reaches deep discharge.

[Soaa-]

I see.  The battery level still needs adjusting then, it refuses to boot even if there's power left.

[Llorean]

Do you get the Toshiba boot screen, and then Rockbox refuses somehow?

[Soaa-]

The standard gigabeat bootsplash shows up, loads halfway and goes into the Rockbox bootloader as usual.  Then it enters Rockbox which panics right away, saying something along the lines of "Low battery!  Shutting down!"  And then it shuts down a few seconds after.

[Llorean]

So, how do you know it has enough power to run Rockbox then?

It's true though that the battery indicator still needs more calibration. I think it stays at 100% for too long as well.

[Soaa-]

A second earlier it was playing music with the battery indicator at 0.  It was running at 0 for at least an hour.

[Llorean]

That's hardly conclusive proof of anything. Rebooting takes power, to spin up the disk and load the firmware images, so your device would've had less power after the reboot than before.

It's possible, though not certain, that your device really did not have enough power to work consistently at that point.

[Soaa-]

I see.  Figuring out exactly what's going on would require more in-depth tests then?

[Llorean]

The battery just needs to be calibrated properly.