From: Uwe Freese <mail_at_uwe-freese.de>
Date: Tue, 4 Feb 2003 22:48:41 +0100

Hello,

As you all may know, getting the voltage in the FM model is a problem,
in details there are these questions:

- can the voltage measured through AN6 when backlight is on? (see AN6 in
  Debug/IO ports screen, it is 0 V when backlight is off)
- which battery scale factor to use? (is it the same as for the
  Recorder?)
- How does the voltage courve of the LiIon battery look like?

Until someone makes a circuit diagram of the boards (which would be the
better choice), again, I'm asking all you FM users for some voltage
measurements:

Open the battery flap, connect a voltage meter to the battery (read
Freds mail where he described on which pins you can measure the voltage)
and measure pairs

(value of AN6 in Debug/IO ports screen when backlight on) and (voltage of battery)

The charger should be disconnected. The harddisk should be off (turn
playback off). I need let's say five value pairs. Let the battery be
differently full. Run the Archos firmware some time to make your battery
more empty.

As Fred wrote, he made a version that "works" (= Rockbox doesn't shut
down) and can be used to make this measurements:

FSU> I did some patching and compilling on the latest CVS (3/02/2003, 20h)
FSU> Now have fun and get the files here :
FSU> http://www.toutfr.com/files/fred/rockbox/
FSU> http://www.toutfr.com/files/fred/rockbox/rb-fm-patched-03.02.2003.ajz

Bye, Uwe.
Received on 2003-02-04