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Raspberry Pi - run program at start-up

There are loads of ways of running a command at start-up in Linux but my favoured approach is to create an initialisation script in /etc/init.d and register it using update-rc.d.  This way the application is started and stopped automatically when the system boots / shutdowns. Create script in /etc/init.d

sudo nano /etc/init.d/NameOfYourScript

The following is an example based on starting up the no-ip service [/usr/local/bin/noip], but change the name of the script and the command to start and stop it and it would work for any command.

#! /bin/sh # /etc/init.d/noip  ### BEGIN INIT INFO # Provides:          noip # Required-Start:    $remote_fs $syslog # Required-Stop:     $remote_fs $syslog # Default-Start:     2 3 4 5 # Default-Stop:      0 1 6 # Short-Description: Simple script to start a program at boot # Description:       A simple script from www.stuffaboutcode.comwhich will start / stop a program a boot / shutdown. ### END INIT INFO # If you want a command to always run, put it here # Carry out specific functions when asked to by the system case "$1" in   start)     echo "Starting noip"     # run application you want to start     /usr/local/bin/noip2     ;;   stop)     echo "Stopping noip"     # kill application you want to stop     killall noip2     ;;   *)     echo "Usage: /etc/init.d/noip {start|stop}"     exit 1     ;; esac exit 0

Warning - its important you test your script first and make sure it doesn't need a user to provide a response, press "y" or similar, because you may find it hangs the raspberry pi on boot waiting for a user (who's not there) to do something!

Make script executable

sudo chmod 755 /etc/init.d/NameOfYourScript

Test starting the program

sudo /etc/init.d/NameOfYourScript start

Test stopping the program

sudo /etc/init.d/NameOfYourScript stop

Register script to be run at start-up To register your script to be run at start-up and shutdown, run the following command:

sudo update-rc.d NameOfYourScript defaults

Note - The header at the start is to make the script LSB compliant and provides details about the start up script and you should only need to change the name.  If you want to know more about creating LSB scripts for managing services, see http://wiki.debian.org/LSBInitScripts If you ever want to remove the script from start-up, run the following command:

sudo update-rc.d -f  NameOfYourScript remove

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Wiring thermometer

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VNC Server

Install tight VNC: “sudo apt-get install tightvncserver"

Run the program: “tightvncserver"

Start a VNC session: “vncserver :1 -geometry 1024x728 -depth 24"

You must use Chicken of the VNC

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Redirect Output to a File

If you want to do the redirection within the Python script, set sys.stdout to an file object does the trick:

import sys sys.stdout = open('file', 'w') print 'test'

A far more common method is to use shell redirection when executing (same on Windows and Linux):

$ python foo.py > file

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Reset Raspberry Pi Serial Port

It seems that this is a known issue with the Raspberry Pi. The GitHub geniePi.c has the following workaround:

Code:

// Try to overcome a bug with the Raspberry Pi (or indeed, any other serial

// port that sends a garbage character when you first open it),

// by sending out dummy characters until we get a NAK back, hopefully

// then the display sequencer will be in a stable state.

    for (i = 0 ; i < 10 ; ++i)

  {

    geniePutchar ('X') ;

    if (genieGetchar () == GENIE_NAK)

      break ;

  }

    return pthread_create (&myThread, NULL, genieReplyListener, NULL) ;

}

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Enabling the serial port

UART

  In order to use the dedicated UART pins on the raspberry pi, first they have to be removed from their default application which is debugging.

To do this edit "/boot/cmdline.txt" and "/etc/inittab".

You can backup this files if you want to return to the default configuration:

cp /boot/cmdline.txt /boot/cmdline.bak

cp /etc/inittab /etc/inittab.bak

Remove "console=ttyAMA0,115200" and "kgdboc=ttyAMA0,115200" configuration parameters from the "/boot/cmdline.txt" configuration file using nano editor.

nano /boot/cmdline.txt

Comment the last line on the "/etc/inittab" file. Put a '#' before "T0:23:respawn:/sbin/getty -L ttyAMA0 115200 vt100.

nano /etc/inittab

Now the RXD (GPIO15) and TXD (GPIO14) pins are available for general UART use.

This is an example application to use the UART pins using Python and the pyserial library:

To install Pyserial download the latest version from http://sourceforge.net/projects/pyserial/files/pyserial/

Install by running the setup.py

python setup.py install

Open a Python terminal (remember to always be running under SuperUser by using sudo or su):

python

To test it without the need of another device simply connect raspberry's TXD and RXD pins to each other:

Run the following commands on the python terminal:

import serial

ser = serial.Serial("/dev/ttyAMA0")

ser.write("UART the Font")

read = ser.read()

print read

ser.close()

The print command should have printed the string sent using the write command. To confugre the UART port, read the following introduction: http://pyserial.sourceforge.net/shortintro.html

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Install "minicom"

Install "minicom" for terminal emulation:

apt-get install minicom

You can use minicom using the next line command

minicom -b 9600 -o -D /dev/ttyAMA0

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Install Serial Driver for Mac

You must install this driver for the Mac to recognize the 4D display and the RFX...

http://www.ftdichip.com/Drivers/VCP.htm

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Get a list of Mac USB ports

ls /dev/tty.usb*

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Open SSL

sudo aptitude install python-openssl

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Profiling

python -m cProfile -s time mine.py

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More profiling

$ sudo apt-get install graphviz $ git clone https://code.google.com/p/jrfonseca.gprof2dot/ gprof2dot $ ln -s "$PWD"/gprof2dot/gprof2dot.py ~/bin $ cd $PROJECT_DIR $ gprof2dot.py -f pstats profile.pstats | dot -Tsvg -o callgraph.svg

http://stackoverflow.com/questions/582336/how-can-you-profile-a-python-script

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Profiling using pycallgraph

Extract pycallgraph-0.5.1.zip and then hop into the directory and run:

python setup.py install

Just before your first line of code you want to graph, put in the following code:

import pycallgraph

pycallgraph.start_trace()

To stop the trace and generate the graph, put in the following code (usually at the end of your program):

pycallgraph.make_dot_graph('test.png')

http://pycallgraph.slowchop.com/pycallgraph/wiki/documentation/0.5.1

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Send notification through to iPhone

http://push.since2006.com/api-push?uid=1033%m&secret=F68XJP&title=new%20alarm&content=hello

App: Push Messenger

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Auto running Python program on startup

cd /home/pi/.config

mkdir autostart

Create a file called mypythonprogram.desktop

[Desktop Entry] Encoding=UTF-8 Type=Application Name=mystartup Comment= Exec=sudo python /home/pi/mystartup.py StartupNotify=false Terminal=false Hidden=false

Store this file in /home/pi/.config/autostart

Restart the Pi

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Setting Up Netifaces on Raspberry Pi

sudo apt-get install python-netifaces