How to control Devices from user space (command line)

Introduction

This page lists the most important devices and drivers that are specific to this board. And how they can be accessed from user space.

Touch Screen

is mapped to

/dev/input/touchscreen

pen down status can be read through

cat /sys/devices/virtual/gpio/gpio157/value

LCD

can be selected by adding "omapdss.def_disp=lcd" to the boot args. This is done by "setenv defaultdisplay lcd " in our boot.scr.

choose from user space by ???

DVI

can be selected by adding "omapdss.def_disp=dvi" to the boot args

power (state=0: off, state=1: on)

echo $state /sys/devices/virtual/gpio/gpio170/value

S-Video

can be selected by adding "omapdss.def_disp=venc" to the boot args

Backlight

power (state=0: off, state=1: on)

echo $state /sys/devices/virtual/gpio/gpio145/value

GPS

power (state=0: off, state=1: on)

echo $state /sys/devices/virtual/gpio/gpio156/value

device file (use 9600 baud)

cat /dev/ttyS1

AUX and Power button

button status can be read through xxx

LEDs are switched through xxx