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AN4503

Troubleshooting

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Troubleshooting

Below is a list of potential problems and corresponding solutions:

 HW setup of the environment:

– While loading the module with the shell command "insmod

/system/lib/hw/<devicename>.ko”, the "minicom" shell of the Host PC should show

the message that the device is correctly probed.

– All the files under the path /sys/class/input/input[x]/device/<busnum>/<i2c-address>

should then be available (in particular, enable_device).

 Data can be seen through the minicom, but it is not exported to /dev/input/event<X>

– There could be problems in the input_allocate_device; check the complete

environment.

– Also verify the correct permissions of the files. In particular, the files enable_device

and pollrate_ms should be 664 at least.

 Data are exported in /dev/input/event<X>, but not seen through the apk.

– Check for problems in the Linux user space or Android Environment.

– The sample application in Section 3.4.2 can be used to verify if the data arrives in the

Linux user space. If it does, the problem is in the Android specific environment; try the

following commands from RAS on the HOST PC:

[RAS]$ adb logcat

or

[RAS]$ adb logcat | grep sensor

to select the relevant messages on that subject.

– A better alternative might be to add some specific logs in order to address the

location of the problem. This can be done by adding "ALOGI("Type of Message")" to

the original code.

 Java Compilation problem of the Root Android Source.

– In case the compilation fails after few minutes, ensure that the Java PATH and choice

are correctly set: Assuming jdk is in /usr/java, then:

$ PATH=/usr/java/jdk1.6.0_45:$PATH

Note:

In some cases, writing "/" at the end of the PATH (i.e. /usr/java/jdk1.6.0_45/) can create

compile problems.

– $ sudo update-alternatives --install "/usr/bin/java" "java"

"/usr/java/jdk1.6.0_45/bin/java" 1

– $ sudo update-alternatives --install "/usr/bin/javac" "javac"

"/usr/javac/jdk1.6.0_45/bin/javac" 1

– $ sudo update-alternatives --install "/usr/bin/javaws" "javac"

"/usr/javaws/jdk1.6.0_45/bin/javaws" 1

– In the /etc/environment, add: export JAVA_HOME='usr/java/jdk1.6.0_45/bin

 Linux is working but Android fails and cannot be seen on the screen.

– Check for error messages relating to framebuffer failure. If there are, verify that the

downloaded “Imgtec” graphics library perfectly matches the PVR driver in the kernel

(in gpu/pvr/), as per Section 2.3.1