Beaglebone: Difference between revisions

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=== beaglebone.local ===
=== beaglebone.local ===
Instead of typing an IP address, we can use [email protected] to access BBB. The software used us Avahi Daemon (Bonjour).  
Instead of typing an IP address, we can use [email protected] to access BBB. The software used us Avahi Daemon (Bonjour).
 
We can manually install it by
<pre>
sudo apt-get update
sudo apt-get install avahi-daemon
</pre>
 
The real IP address can be found by '''ping HOSTNAME.local'''.


=== microHDMI to VGA cable ===
=== microHDMI to VGA cable ===

Revision as of 17:31, 27 November 2013

Official website

Basic

Wiki

Ubuntu

  1. wget the image
  2. Use sudo su instead su to have full root permission. Use xz command to write the image to microSD
  3. Insert microSD to BBB and holding the button (closest to microSD) while applying power on BBB
  4. To copy the image to eMMC, use wget again to get the image file. Use sudo su instead su to have full root permission. Then use xz command again to write the image to eMMC.
  5. Remove microSD and reboot BBB. If we keep microSD in BBB, it will boot from microSD. MicroSD has the advantage that we can extend the space while eMMC cannot.
  6. At the beginning, the "/" partition still has 1.4GB space (see table below). If we boot into microSD and follow the instruction to expand the microSD file system, we can make use whole space in uSD.
root@ubuntu-armhf:/home/ubuntu# df -h
Filesystem      Size  Used Avail Use% Mounted on
rootfs          1.8G  295M  1.4G  18% /
/dev/root       1.8G  295M  1.4G  18% /
devtmpfs        248M  4.0K  248M   1% /dev
none            4.0K     0  4.0K   0% /sys/fs/cgroup
none             50M  232K   50M   1% /run
none            5.0M     0  5.0M   0% /run/lock
none            248M     0  248M   0% /run/shm
none            100M     0  100M   0% /run/user
/dev/mmcblk0p1 1004K  466K  538K  47% /boot/uboot
  • Kernel is 3.8.
  • The image contains a miniminal Ubuntu system. It only takes 276 MB when I use df -h command to check. So it does not come with a full desktop.
  • Defautl username=ubuntu, password=ubuntu
  • http://robotic-controls.com/learn/beaglebone/beaglebone-black-ubuntu
  • If I try to install xubuntu-desktop, it requires 421MB data to download and 1.2GB space to install. So it is not feasible since the /dev/mmcblk0p2 partition has only 1.8GB space. Fortunately, the solution in here works well.
  • Unfortunately, I got an error when I issue 'startx'.
Fatal server error:
AddScreen/ScreenInit failed for driver 0

Please check the log file at "/var/log/Xorg.0.log" for additional informaiton.

After I reboot, things looks better. I can get a login GUI. However, the system is very slow and I can not see mouse on the desktop.

Angstrom

# Umount the uSD card 
mount # find /dev/sdc1
sudo diskfutil unmount /dev/sdc1
ls *.xz

# Copy img file to microSD card. Took about 15-30 minutes.
# Method 1.
tar -xJf BBB-eMMC-flasher-2013.06.20.img.xz
sudo dd bx=1m if=~/Downloads/BBB-eMMC-flasher-2013.06.20.img of=/dev/sdc
sudo sync
# Method 2.
xz -cd BBB-eMMC-flasher-2013.06.20.img.xz > /dev/sdc

Remove the microSD card and insert it fully into BBB uSD card slot.

To flash the BBB: Hold down the 'user boot' button (closes to uSD card slot) and power on BBB until the 4 LED's light up for a few seconds. It will take 30-45 minutes to flash the image onto the eMMC. Once it's done, the 4 LED's will all stay lit up at the same time. You can then power down your BBB, remove uSD and power up BBB.

The username is root. There is not password. We can access it by ssh [email protected].

beaglebone.local

Instead of typing an IP address, we can use [email protected] to access BBB. The software used us Avahi Daemon (Bonjour).

We can manually install it by 

sudo apt-get update
sudo apt-get install avahi-daemon

The real IP address can be found by ping HOSTNAME.local.

microHDMI to VGA cable

http://circuitco.com/support/index.php?title=BeagleBone_Black_Accessories

Question: How to create EDIT? My NEC monitor supports only 1024 x 768.

Beagleboneblack HDMI page from circuitco.com.

My Observation about angstrom distribution

When I use the image BBB-eMMC-flasher-2013.06.20.img to put it on the microSD card with win32DiskImager, I see (from plugging SD in Ubuntu) the microSD card has 2 partitions 

eMMC-Flasher  -ext4
BEAGLE_BONE - vfat

where eMMC-Flasher contains an ubuntu data and BEAGLE_BONE contains only 4 files. 

ID.txt - just one line
MLO - 98K binary
u-boot.img - 371K binary
uEnv.txt - just one line

Flashing is done by pressing the 'Boot' button while connecting the power. It took 1 hour in my case when I flashed BBB-eMMC-flasher-2013.06.20.img.

However, once the microSD is flashed to eMMC, the 'eMMC-Flasher' partition will be gone and 'BEAGLE_BONE' partition is changed to include 3 new folders- App, Docs and Drivers AND some new files - START.htm, autorun.inf, README.md.

Android OS

http://icculus.org/~hendersa/android/

Books

BBB vs Raspberry Pi

Beaglebone 101

My created screenshots http://goo.gl/o03iex

Configure Angstrom

http://www.gigamegablog.com/2012/01/29/beaglebone-linux-101-configuring-angstrom-linux/

Package download

opkg update
opkg install XXXX
opkg list | grep "gfortran"

However, at least for BBB case, I cannot find gfortran package so I cannot install R. See discussions below

The angstrom linux package browser is the place we can see if packages for BBB Cortex-A8. According to Wikipedia the Cortex-A8 has armv7a architecture.

On ubuntu, we can use ldconfig -v command to show the installed libraries and their versions. See here. If we like to manually add libraries to ubuntu/debian, we can check the tip here.

Ubuntu

Find out the IP address if we use internet sharing

Download fing deb package from overlooksoft website. Install it by double clicking the file in file manager. Issue the following command to find out the IP of beaglebone black (shared computer). The IP of my 2nd ethernet adapter (eth1) is 10.42.0.1. 

sudo fing -n 10.42.0.1/24

Wifi setup command line

dmesg | grep rtl8192
ifconfig wlan0
sudo apt-get install wireless-tools
iwconfig
sudo nano /etc/network/interface
# Made appropriate change on /etc/network/interface
sudo ifup wlan0 // not needed if we have enable wlan0 at boot. 
                // sudo ifconfig wlan0 up
sudo iwlist wlan0 scanning
ping www.google.com

where the file /etc/network/interface should be like 

auto wlan0
iface wlan0 inet dhcp
    wpa-ssid mynetworkname
    wpa-psk mysecretpassphrase

Fix date/time

See here. Run the following to change the country and time zone. 

sudo dpkg-reconfigure tzdata

VNC

opkg update
opkg install x11vnc

x11vnc -bg -o %HOME/.x11vnc.log.%VNCDISPLAY -auth /var/run/gdm/auth-for-gdm*/database -display :0  -forever

Start VNC server at bootup and shutdown

Use microSD as ext storage

It is possible. See the idea in here.

Build R on BBB

I am using Ubuntu 13.04 image since angstrom linux missing many required packages.

Since the space is limited, instead of using 'sudo apt-get build-dep r-base', I manually install the essential packages: build-essential, gfortran, libreadline6-dev, libx11-dev, libxt-dev and optionally openjrk-7-jre.

I am using R 3.0.1. 

ubuntu@ubuntu-armhf:~$ df -h
Filesystem      Size  Used Avail Use% Mounted on
/dev/mmcblk0p2  1.8G  276M  1.4G  17% /
none            4.0K     0  4.0K   0% /sys/fs/cgroup
devtmpfs        248M  4.0K  248M   1% /dev
none             50M  220K   50M   1% /run
none            5.0M     0  5.0M   0% /run/lock
none            248M     0  248M   0% /run/shm
none            100M     0  100M   0% /run/user
/dev/mmcblk0p1 1004K  472K  532K  48% /boot/uboot

sudo apt-get update
sudo apt-get install build-essential
sudo apt-get install gfortran
sudo apt-get install libreadline6-dev
sudo apt-get install libx11-dev
sudo apt-get install libxt-dev
sudo apt-get install openjdk-7-jre    
// (optional) need it if we don't want to get an error message at the end of running 'make'
// This require 143MB space.

// The whole process (configure + make) takes at least 2 hours on BBB
./configure
make
// make > ~/Rmake.txt 2>&1

There is still warnings with library/datasets
http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=695411
It seems this is false alarm.

ubuntu@ubuntu-armhf:~/R-3.0.1$ df -h
Filesystem      Size  Used Avail Use% Mounted on
/dev/mmcblk0p2  1.8G  1.1G  615M  64% /
none            4.0K     0  4.0K   0% /sys/fs/cgroup
devtmpfs        248M  4.0K  248M   1% /dev
none             50M  224K   50M   1% /run
none            5.0M     0  5.0M   0% /run/lock
none            248M     0  248M   0% /run/shm
none            100M     0  100M   0% /run/user
/dev/mmcblk0p1 1004K  472K  532K  48% /boot/uboot

The complete process of running ./configure and make are recorded in

Performance test

GPIO Projects

Setting up an IO python library (GPIO, PWM, ADC, I2C, SPI, UART)

http://learn.adafruit.com/setting-up-io-python-library-on-beaglebone-black

  • PWM: P8_13, P8_34, P8_36, P8_45, P8_46, P9_14, P9_21, P9_22, P9_29, P9_42. Eg. blink LED, fading LED, servo.
  • ADC: P9_33, P9_35, P9_36, P9_37, P9_38, P9_39, P9_40. Eg. measure light, ultrasonic sensor, accelerometer, joystick, Potentiometer.
  • I2C: P9_19, PI_20. Eg. temperature/pressure sensors.
  • SPI: P9_17, P9_18, P9_21, P9_22, P9_28, P9_29, P9_30, P9_31.
  • UART: 17 pins.

Adding a push button

http://learn.adafruit.com/connecting-a-push-button-to-beaglebone-black

Measure light

http://learn.adafruit.com/measuring-light-with-a-beaglebone-black My example: 

import Adafruit_BBIO.ADC as ADC
import time
from time import localtime, strftime

sensor_pin = 'P9_40'

ADC.setup()

#print('Reading\t\tVolts')
print time.asctime(time.localtime(time.time())), '\tReading\t\tVolts'

while True:
    reading = ADC.read(sensor_pin)
    volts = reading * 1.800
    #print('%f\t%f' % (reading, volts))
    #print(strftime("%Y-%m-%d %H:%M:%S", localtime()))
    print time.asctime(time.localtime(time.time())), '\t%f\t%f' % (reading, volts)
    time.sleep(60)

which can be run (and the output was written to a file for logging) 

sudo python light.py > tmp.txt

If we want, we can follow the tutorial in here to have the light reading logged on the COMS or send to google docs like [1]. Alternatively, we can let BBB to send an email to you like here.

Fading RGB using PWM

http://learn.adafruit.com/fading-a-rgb-led-on-beaglebone-black/overview

Blinking an LED

http://learn.adafruit.com/blinking-an-led-with-beaglebone-black

Controlling a servo

We can actually try the following simpler approach using bonescript without bothering a command line. Just open a browser tab and type the address http://beagleboard.org/Support/BoneScript/ServoMotor/. It just works! The SG90 micro motor operators at 4.0 to 7.2 volts according to here.

BBBservo.jpg

Measuring temperature

http://learn.adafruit.com/measuring-temperature-with-a-beaglebone-black

HC-SR04 (5v) sonar sensor

http://www.youtube.com/watch?v=bssyOCcU_Q4

Connect to 5v device

See 3.2.4 of the book "Bad to the Bone".

Input voltage & voltage divider

http://beagleboard.org/Support/BoneScript/accelerometer/

PIR motion sensor (ADC)

http://beagleboard.org/Support/BoneScript/PIRMotionSensor

Pull-up Resistor

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