User:MartinDengler

About Me

I program for a living and got an XO to support the OLPC project and have a laptop for daily use in one go.

I work with python and Fedora a lot.

Screen battery status hint

The only thing I've ever contributed so far is a tiny developer-only hint:

Date: Sat, 5 Jan 2008 18:09:19 +0000
From: Martin Dengler <martin@martindengler.com>
Subject: Battery capacity in screen hardstatus line hint
To: devel@lists.laptop.org

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Hi,

In case this is of use to anyone, I've put the battery capacity in my
xo screen instance's hardstatus line with this tiny script & screenrc
change:

---------- /home/olpc/bin/olpc_screen_status.sh
#!/bin/bash
# Author: Martin Dengler <martin@martindengler.com>
# idea from http://www.mail-archive.com/screen-users@gnu.org/msg00322.html
# based on battery info from olpc-logbat
#
B_INFO=/sys/class/power_supply/olpc-battery

while true
do
    CAP=`cat $B_INFO/capacity`
    echo b:$CAP%
    sleep 60
done
----------

....screenrc change:

---------- /home/olpc/bin/.screenrc
# run command forever and assign most recent output to string escape %1`  
backtick 1 0 0 /home/olpc/bin/olpc_screen_status.sh

# the ...%1`... part at the end is the important part
hardstatus alwayslastline "%{.bW}%-w%{.rW}%n %t%{-}%+w %=%{..G} %H %{..Y} %m/%d %C%a %1` "
----------

I'd be interested to know how to get at the ambient temperature sensor mentioned in section 2.4.1 of the CL1 hardware design specification PDF. I've had a look around /sys/class but nothing's jumped out at me.

Ambient temperature tracking

I found some trac bugs (#800 and #1285) that gave me a hint as to where the ambient temperature sensor's data are available:

cat /sys/class/power_supply/olpc_battery/temp_ambient

I saw it earlier but was led to believe the ambient temperature sensor was on the motherboard, not the battery. I'm not sure if this is the case; either it is, and the data being available under power_supply/olpc_battery is (at best) just confusing, or this is a temperature sensor on the battery and not the motherboard ambient temperature sensor that I'm looking for.

How to explicitly forget/add a WPA wireless network

If you want to forget/add a WPA wireless network explicitly, edit

/home/olpc/.sugar/default/nm/networks.cfg