Tips, Useful Commands, Programs And Links

TIPS

Read temperature sensor (value/1000 = temperature ºC):

$ cat /sys/class/thermal/thermal_zone0/temp

47078

Disable LAN9512 (this chip consume arounfd 200mA):

$ echo 0x00 > /sys/devices/platform/bcm2708_usb/buspower

Enable LAN9512 (this chip consume arounfd 200mA):

$ echo 0x01 > /sys/devices/platform/bcm2708_usb/buspower

HOW TO CHECK THE WATCHDOG

First of all, you will have to have this script in he /etc/init.d folder:

Quote Edit Delete

He añadido un script en /etc/init.d/S15watchdog para activar y configurar el watchdog:

#!/bin/sh

#

# Start watchdog

#

case "$1" in

start)

        echo "Starting watchdog..." 

        watchdog -t 5 /dev/watchdog

        ;;

stop)

        ;;

restart|reload)

        ;;

*)

        echo $"Usage: $0 {start|stop|restart}" 

        exit 1

esac

exit $?

Para probar que el watchdog funciona correctamente, provoco un kernel panic con la siguiente línea:

And in order to force a block you will have to execute:

# sync; sleep 2; sync; echo c > /proc/sysrq-trigger

USEFUL COMMANDS FOR RASBPIAN OS

rasp-config: is a tool to config the raspberry pi. You can learn more about this command in this link link.

apt-get install name_application: install an application.

apt-get remove name_application: remove an application.

apt-get update: update list of repositories.

apt-get upgrade: update the system.

rpi-update: is a tool to upgrade the firmware. An easier way to update the firmware of your Raspberry Pi.

For read temperature: cat /sys/class/thermal/thermal_zone0/temp

#!/bin/sh

# /**

#  @file read_temperature.sh

#  @author  Oscar Gomez Fuente <oscargomezf@gmail.com>

#  @ingroup iElectronic

#  @date 02/05/2014

#  @version 1.0.0

#  @section DESCRIPTION

#   script to read RPi's temperature

#  */

value=$(echo "scale=2; $(cat /sys/class/thermal/thermal_zone0/temp)/1000" | bc)ºC

echo "RPi temperature: $value" 

USEFUL PROGRAMS

scrot: is a minimalistic command line screen capturing application link.

USING HDMI-LCD 800x480 WITH TOUCH SCREEN

Open /boot/config.txt and add these lines:

Hdmi_force_hotplug = 1

Hdmi_group = 2

Hdmi_mode = 1

Hdmi_mode = 87

Hdmi_cvt 800 480 60 6 0 0 0

Start_file = start_x.elf

Fixup_file = fixup_x.elf

LINKS

Raspberry Pi Cookbook