View source for Premiers pas avec BeagleBone Black



==Démarrage==

Connecter l'USB du [[BeagleBone Black]]. Une fois qu'il est visible (comme un disque : /media/BEAGLEBONE), on peut se connecter dessus : http://192.168.7.2

L'environnent de développement [[Cloud9]] est aussi accessible depuis http://192.168.7.2:3000


Des que cela fonctionne, on peut y aller par ssh (mot de passe vide)
<pre>
ssh root@192.168.7.2
</pre>
Il n'y a pas de mot de passe. Par sécurité, mettre un mot de passe ou déployer une clé publique pour SSH.

==Test des GPIO depuis le shell==



Test des LED USR0123
<pre>
cd /sys/class/leds
ls -F
cd beaglebone\:green\:usr0
ls -F
cat trigger 
echo none > trigger
echo oneshot > trigger
echo heartbeat > trigger
echo 1 > brightness 
echo 0 > brightness 
echo timer > trigger
echo 100 > delay_on
echo 900 > delay_off
</pre>


Test des GPIO (write)
<pre>
# attach a LED at gpio1_28 (1*32+28=60) with a 220 ohms resistor
cd /sys/class/gpio
ls -F
echo 60 > export
cd gpio60
echo out > direction
echo 1 > value
cd ..
echo 60 > unexport
</pre>

Test des GPIO (analog read)
<pre>
TBD
</pre>


Test des GPIO (digital read) : mettre un bouton en pullup sur 60 9_28 ? (=1*32+28)
<pre>
#!/bin/sh
#
# Read a GPIO input 
# Author : http://wh1t3s.com/2009/05/14/reading-beagleboard-gpio/

GPIO=$1

cleanup() { # Release the GPIO port
  echo $GPIO > /sys/class/gpio/unexport
  echo ""
  echo ""
  exit
}

# Open the GPIO port
#
echo "$GPIO" > /sys/class/gpio/export
echo "in" > /sys/class/gpio/gpio${GPIO}/direction

trap cleanup SIGINT # call cleanup on Ctrl-C

THIS_VALUE=`cat /sys/class/gpio/gpio${GPIO}/value`
LAST_VALUE=$THIS_VALUE
NEWLINE=0

# Read forever

while [ "1" = "1" ]; do
  # next three lines detect state transition
  if [ "$THIS_VALUE" != "$LAST_VALUE" ]; then
    EV="|"
  else
    EV=""
  fi

  # "^" for high, '_' for low
  if [ "1" = "$THIS_VALUE" ]; then
    EV="${EV}^"
  else
    EV="${EV}_"
  fi
  echo -n $EV

  # sleep for a while
  sleep 0.05

  # wrap line every 72 samples
  LAST_VALUE=$THIS_VALUE
  THIS_VALUE=`cat /sys/class/gpio/gpio${GPIO}/value`
  NEWLINE=`expr $NEWLINE + 1`
  if [ "$NEWLINE" = "72" ]; then
    echo ""
    NEWLINE=0
  fi

done

cleanup # call the cleanup routine
</pre>

<pre>
chmod 755 ./read_gpio.sh
./read_gpio.sh 60
</pre>

===Ressources===
* http://elinux.org/EBC_Exercise_02_Flashing_an_LED
* http://www.armhf.com/index.php/using-beaglebone-black-gpios/
* http://emmanuel.pouly.free.fr/beagle2.html
* ''TI has more comprehensive information at: http://processors.wiki.ti.com/index.php/GPIO_Driver_Guide  In particular, there's information that describes how to control the pin direction.''

==Test des GPIO en Python==

<pre>
import os
import time
def test(command):
print command
os.popen(command)
test(“echo 60 > /sys/class/gpio/export”)
test(“echo high > /sys/class/gpio/gpio60/direction”)
test(“echo 1 > /sys/class/gpio/gpio60/value”)
value = 1
for i in range(0,10):
if value == 1:
value = 0
else:
value = 1
test(“echo ” + str(value) + ” > /sys/class/gpio/gpio60/value”)
time.sleep(2)
test(“echo 60 > /sys/class/gpio/unexport”)
</pre>

===Ressources===
* http://andrewatthewood.wordpress.com/2013/06/02/beaglebone-black-gpio-c-and-python/

==C++==
===Ressources===
* Bibliothèque C++ pour contrôler divers écrans LCD https://github.com/majestik666/Beagle_GPIO : [http://www.youtube.com/watch?v=0JYtD60L9o4&feature=plcp vidéo de démo]

==Configuration Réseau==

Sur le BeagleBone
<pre>
route add default gw 192.168.7.1
</pre>

Mettre un DNS dans /etc/resolv.conf (par exemple : cat /etc/resolv.conf sur le PC, vous prenez la 1ère ligne "nameserver X.X.X.X" et vous la mettez dans /etc/resolv.conf sur le BeagleBone).
<pre>
nameserver 192.168.7.1
nameserver 8.8.8.8
</pre>


Sur le PC qui sert de passerelle (celui où est connecté l'USB) :
<pre>
sudo iptables --append FORWARD --in-interface eth2 -j ACCEPT
sudo iptables --table nat --append POSTROUTING --out-interface eth1 -j MASQUERADE
</pre>

Note : sur ma machine, eth1 = l'I/F réseau du PC, et eth2 = la connexion filaire via USB (faire "ifconfig -a" pour vérifier, sinon adapter les commandes ci-dessus).

Vérifier que  /proc/sys/net/ipv4/ip_forward contient "1" . Sinon: 
<pre>sudo bash -c "echo 1 > /proc/sys/net/ipv4/ip_forward"</pre>

Et voilà... Depuis le BeagleBone, je peux pinger n'importe quelle adresse
<pre>
ping beaglebone.org
ping 8.8.8.8
nslookup www.google.com
</pre>

==Configuration du temps==
'''Attention : les mises à jour et les installations via [[npm]] requièrent une horloge mise à jour'''

voir http://derekmolloy.ie/automatically-setting-the-beaglebone-black-time-using-ntp/

<pre>
date
ntpdate -b -s -u pool.ntp.org
date
</pre>

==Ajout d'une clé Wifi==
https://learn.adafruit.com/setting-up-wifi-with-beaglebone-black/overview

==Activation des 5 UART supplémentaires==
http://beaglebone.cameon.net/home/serial-ports-uart
* voir aussi [http://hipstercircuits.com/enable-serialuarttty-on-beaglebone-black/ Enable serial/UART/tty on BeagleBone Black]

Ajouter à /boot/uboot/uEnv.txt avec vim/nano
<pre>
##Enable on-board serial ports http://beaglebone.cameon.net/home/serial-ports-uart
optargs=quiet drm.debug=7 capemgr.enable_partno=BB-UART1,BB-UART2,BB-UART4,BB-UART5
</pre>
puis 
<pre>reboot</pre>

<pre>ls -l /dev/ttyO*</pre>

==[[Node.js]]==
'''Attention : les mises à jour et les installations via [[npm]] requièrent une horloge mise à jour'''

[[Node.js]] est installé par défaut. Il sert le serveur web embarqué.
La bibliothèque [https://github.com/jadonk/bonescript bonescript] donne accès aux GPIO de la carte.

===Led toggling===
Copier ce code dans un fichier blinking.js pris dans le livre [http://beagleboard.org/bad-to-the-bone Bad to the Bone: Crafting Electronics Systems with BeagleBone and BeagleBone Black].

<pre>

var b = require('bonescript');

//Old bonescript defines 'bone' globally
var pins = (typeof bone != 'undefined') ? bone : b.bone.pins;

var ledPin = pins.P8_13;
var ledPin2 = pins.USR3;

b.pinMode(ledPin, b.OUTPUT);
b.pinMode(ledPin2, b.OUTPUT);

var state = b.LOW;
b.digitalWrite(ledPin, state);
b.digitalWrite(ledPin2, state);

setInterval(toggle, 1000);

function toggle() {
    if(state == b.LOW) state = b.HIGH;
    else state = b.LOW;
    b.digitalWrite(ledPin, state);
    b.digitalWrite(ledPin2, state);
}
</pre>

<pre>
node blinkled.js
</pre>

===Led on / off===
Un autre exemple
<pre>
var led = process.argv[2];
var mode = process.argv[3];

var b = require('bonescript');

b.pinMode(led, b.OUTPUT);

if(mode == "ON") state = b.HIGH; else state = b.LOW;

b.digitalWrite(led, state);
</pre>

<pre>
node led.js USR0 ON
node led.js USR1 OFF
node led.js USR2 ON
node led.js USR3 OFF
</pre>

===Analog read===
Un autre exemple
<pre>
var b = require('bonescript');
var apin = process.argv[2];
b.analogRead(apin, printStatus);
function printStatus(x) {
    console.log( x.value);
}
</pre>

<pre>
node analogread.js P9_33
node analogread.js P9_35
node analogread.js P9_37
node analogread.js P9_39
node analogread.js P9_36
node analogread.js P9_38
node analogread.js P9_40
</pre>

==JDK==
Télécharger le JDK d'Oracle : JDK 7 version "Linux ARM v6/v7 Soft Float ABI".

Le copier sur le Beagle via scp; exemple :
<pre>
scp jdk-7u45-linux-arm-vfp-sflt.tar.gz root@192.168.7.2:/home/root
</pre>

Décompresser le tar.gz

<pre>
export PATH=$PATH:/home/root/jdk1.7.0_45/bin
export JAVA_HOME=/home/root/jdk1.7.0_45

java -version
</pre>

Ajouter les 2 exports au .bashrc

==[[OpenHAB]]==
Télécharger OpenHAB

Le copier sur le Beagle via scp; exemple :
<pre>
scp openhab.tgz root@192.168.7.2:/home/root
</pre>

Décompresser le tgz

<pre>
cd openhab
bin/start.sh
</pre>

Naviguer sur http://192.168.7.2:8080/openhab.app?sitemap=demo

Il reste plus qu'à ajouter des règles avec le binding exec pour contrôler les GPIO du Beaglebone.




Liens:
* http://tuxtec.blogspot.fr/2013/11/installing-openhab-on-beaglebone-black.html

==[[Node-RED]]==
'''Attention : les mises à jour et les installations via [[npm]] requièrent une horloge mise à jour'''

Voir http://nodered.org/docs/hardware/beagleboneblack.html

Charger et déployer ce flow pour faire clignoter les LED USR2 et USR3 du BBB 
<pre>
[{"id":"b1fce44.9ce3c18","type":"inject","name":"on","topic":"","payload":"1","repeat":"","once":false,"x":127.16666412353516,"y":109.16666412353516,"wires":[["b2a66e5e.6da6f"]]},{"id":"591aef4d.b55f38","type":"inject","name":"off","topic":"","payload":"0","repeat":"","once":false,"x":127.16666412353516,"y":149.16666412353516,"wires":[["b2a66e5e.6da6f"]]},{"id":"36f2a960.164f76","type":"inject","name":"tick","topic":"","payload":"","repeat":"1","once":false,"x":127.16666412353516,"y":49.166664123535156,"wires":[["7ee460bc.df48e"]]},{"id":"55249ec9.21e61","type":"debug","name":"","active":true,"x":567.1666641235352,"y":89.16666412353516,"wires":[]},{"id":"7ee460bc.df48e","type":"function","name":"Toggle USR3 LED on input","func":"\nvar pin = \"USR3\"\nvar b = context.global.bonescript;\ncontext.state = context.state || b.LOW;\n\nb.pinMode(pin, b.OUTPUT);\n\n(context.state == b.LOW) ? context.state = b.HIGH : context.state = b.LOW;\nb.digitalWrite(pin, context.state);\n\nreturn msg;","outputs":1,"x":347.16666412353516,"y":69.16666412353516,"wires":[["55249ec9.21e61"]]},{"id":"b2a66e5e.6da6f","type":"function","name":"Set USR2 LED on input","func":"\nvar pin = \"USR2\";\nvar b = context.global.bonescript;\n\nb.pinMode(pin, b.OUTPUT);\n\nvar level = (msg.payload === \"1\")?1:0;\nb.digitalWrite(pin, level);\n\nreturn msg;","outputs":1,"x":347.16666412353516,"y":129.16666412353516,"wires":[["55249ec9.21e61"]]}]
</pre>


http://nodered.org/docs/hardware/arduino.html
Charger et déployer ce flow pour faire clignoter la LED 13 de l'Arduino branché sur le port USB du BBB 
<pre>
npm install firmata
</pre>

Le port est /dev/ttyACM0
<pre>
[{"id":"d7663aaf.47194","type":"arduino-board","repeat":"25","device":"/dev/ttyACM0"},{"id":"8c09ca6c.a975d","type":"arduino out","name":"","pin":"13","state":"OUTPUT","arduino":"d7663aaf.47194","x":509.16667556762695,"y":162.16666984558105,"wires":[]},{"id":"e37b6a97.610968","type":"inject","name":"tick","topic":"","payload":"","repeat":"0.5","once":false,"x":116.16668319702148,"y":62.16666507720947,"wires":[["60b4aeaa.800d58"]]},{"id":"60b4aeaa.800d58","type":"function","name":"Toggle output on input","func":"\n// initialise level as a context variable if currently undefined \n// (context variables persist between calls to the function)\ncontext.level = context.level || false;\n\n// if it's a 0 make it a 1 else make it a 0...\ncontext.level = !context.level;\n\n// set the payload to the level and return\nmsg.payload = context.level;\nreturn msg;","outputs":1,"x":298.1666793823242,"y":113.16665458679199,"wires":[["8c09ca6c.a975d"]]}]
</pre>

==[[Arduino]]==
'''Attention : les mises à jour et les installations via [[npm]] requièrent une horloge mise à jour'''

avec [[Firmata]] et [[Node.js]] : TBD avec [[Node.js#Arduino_avec_Firmata]]

Le port de l'Arduino est /dev/ttyACM0

http://www.instructables.com/id/How-to-make-a-BeagleBone-and-an-Arduino-communicat/

Future carte Arduino TRE : http://beagleboard.org/blog/2013-10-03-beagleboardorg-collaborates-with-arduino/

==[[XBMC]]==

* http://beagleboard.org/project/xbmc/

==[[OpenCV]]==
* http://emmanuel.pouly.free.fr/beagle5.html
==[[GStreamer]]==
* http://www.oz9aec.net/index.php/beaglebone/476-turning-the-beaglebone-into-a-high-definition-ip-camera

==[[MQTT]]==
* http://www.eclipse.org/paho/TalkingSmall.html

En Python avec Paho Python

Il faut installer le package Adafruit_BBIO ([https://github.com/adafruit/adafruit-beaglebone-io-python lien])

<pre>
import time

import Adafruit_BBIO.ADC as ADC

import paho.mqtt.client as mqtt

sensor_pin = 'P9_40'

ADC.setup()

mqttc = mqtt.Client()

mqttc.connect("m2m.eclipse.org", 1883, 60)

mqttc.loop_start()

while True:

  reading = ADC.read(sensor_pin)

  millivolts = reading * 1800  # 1.8V reference = 1800 mV

  temp_c = (millivolts - 500) / 10

  print('mv=%.2f C=%.2f' % (millivolts, temp_c))

  mqttc.publish("bbbexample/tmp36/mv","%.2f" % millivolts);

  mqttc.publish("bbbexample/tmp36/c","%.2f" % temp_c);

  time.sleep(1)[a]

</pre>

==BBB contrôlant [[Dagu Wild Thumper 6WD Chassis]]==
TBD
* [[Dagu Wild Thumper 6WD Chassis]]
* [[Monster Moto Shield]] (+ peut être [[Arduino]])
* Webcam Logitech C270 
* Clé Wifi
* Mini-USB Hub