Circuidipity _ Getting Started With BeagleBone Black

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Howdy! Archives Monday 02 September 2013

Getting Started with BeagleBone Black

Raspberry Pi, Arduino, OpenWRT on routers ... Happy days are here for open source on little

computers! Five years ago BeagleBoard.org released its first hacker-friendly ARM-powered

development board and now I am having fun exploring their brand new BeagleBone Black - a $45

community-supported Linux computer.

Step 0 - Out-of-Box

The original BeagleBone - released near the end of 2011 - started with the idea of making an ARM

board that would fit in a small mint tin and see how much awesomesauce could be packed inside!

BeagleBone Black (BBB) has the same convenient size, rounded corners, and 4 mounting holes for

building projects. Onboard is a 1GHz ARMv7 processor, 512MB RAM, 2GB storage, microSD slot, a

microUSB port for power and connectivity, a USB host port, microHDMI, 5V power connector, and -

as I am having fun exploring - 96 header pins for interfacing BBB with external hardware. A

microUSB-to-USB cable is included for connecting BBB to a host machine.

BeagleBone Black is completely open source ... hardware schematics are provided (build your own!),

no binary blobs, no NDA required to dive into the 4,000+ pages(!) of Texas Instruments' AM335x

processor manual. BBB ships with the Angstrom Linux distribution pre-installed ... but using an

ARMv7 processor is a big plus because alternative ARM ports of the mainstream Linux distros (such

as Debian) are available for the BBB without re-compiling packages. BBB is also one of the first

ARM devices to fully embrace the Linux Device Tree and will benefit from ongoing ARM

improvements in mainstream kernel development and make it easier to create expansion boards

(or capes in BBB lingo) for the device.

Step 1 - Connect to Host

BeagleBone Black is designed to get the Linux user up-and-running quickly. Within a few minutes

of unboxing the device I was using the provided USB cable to connect the device to my host

computer (running Debian sid). BBB mounts as a usb-storage device and provides a usbnet virtual-

ethernet interface running a DHCP server.

Some post-connection HOST output of interest ...

$ cat /var/log/kern.log

http://www.circuidipity.com/

http://www.circuidipity.com/archives.html

http://beagleboard.org/Products/BeagleBone%20Black

http://circuitco.com/support/index.php?title=BeagleBoneBlack#Hardware_Files

http://www.raspberrypi.org/faqs

http://www.ti.com/product/am3359

http://linuxgizmos.com/introducing-the-new-beaglebone-black-kernel



Sep 1 16:58:17 kambei kernel: [455195.036280] usb 1-1.2: new high-speed USB device number 20 using ehci-pci

Sep 1 16:58:18 kambei kernel: [455195.129344] usb 1-1.2: New USB device found, idVendor=1d6b, idProduct=0104

Sep 1 16:58:18 kambei kernel: [455195.129350] usb 1-1.2: New USB device strings: Mfr=2, Product=3, SerialNumber

Sep 1 16:58:18 kambei kernel: [455195.129355] usb 1-1.2: Product: BeagleBoneBlack

Sep 1 16:58:18 kambei kernel: [455195.129358] usb 1-1.2: Manufacturer: Circuitco

Sep 1 16:58:18 kambei kernel: [455195.129361] usb 1-1.2: SerialNumber: 5A-1713BBBK2013

Sep 1 16:58:18 kambei kernel: [455195.133166] rndis_host 1-1.2:1.0 eth1: register 'rndis_host' at usb-0000:00:1a.0-1.2, RNDIS device, c8:a0:30:ac:1d:6f

Sep 1 16:58:18 kambei kernel: [455195.133843] cdc_acm 1-1.2:1.2: This device cannot do calls on its own. It is not a modem.

Sep 1 16:58:18 kambei kernel: [455195.133917] cdc_acm 1-1.2:1.2: ttyACM0: USB ACM device

Sep 1 16:58:18 kambei kernel: [455195.135249] usb-storage 1-1.2:1.4: USB Mass Storage device detected

Sep 1 16:58:18 kambei kernel: [455195.135458] scsi20 : usb-storage 1-1.2:1.4

Sep 1 16:58:19 kambei kernel: [455196.133604] scsi 20:0:0:0: Direct-Access Linux File-CD Gadget 0308 PQ: 0 ANSI: 2

Sep 1 16:58:19 kambei kernel: [455196.134045] sd 20:0:0:0: Attached scsi generic sg1 type 0

Sep 1 16:58:19 kambei kernel: [455196.135313] sd 20:0:0:0: [sdb] 144522 512-byte logical blocks: (73.9 MB/70.5 MiB

Sep 1 16:58:19 kambei kernel: [455196.136080] sd 20:0:0:0: [sdb] Write Protect is off

Sep 1 16:58:19 kambei kernel: [455196.136089] sd 20:0:0:0: [sdb] Mode Sense: 0f 00 00 00

Sep 1 16:58:19 kambei kernel: [455196.136840] sd 20:0:0:0: [sdb] Write cache: enabled, read cache: enabled, doesn

Sep 1 16:58:19 kambei kernel: [455196.147108] sdb:

Sep 1 16:58:19 kambei kernel: [455196.149998] sd 20:0:0:0: [sdb] Attached SCSI removable disk

$ lsusb

Bus 001 Device 020: ID 1d6b:0104 Linux Foundation Multifunction Composite Gadget

$ mount

/dev/sdb on /media/dwa/BEAGLEBONE type vfat (rw,nosuid,nodev,relatime,uid=1000,gid=1000,fmask=0022,dmask=0077,codepage

$ ls /dev/ttyA*

crw-rw---T 1 root dialout 166, 0 Aug 18 13:30 /dev/ttyACM0

$ ifconfig

eth0 Link encap:Ethernet HWaddr f0:de:f1:15:e8:51

inet addr:192.168.1.4 Bcast:192.168.1.255 Mask:255.255.255.0

inet6 addr: fe80::f2de:f1ff:fe15:e851/64 Scope:Link

UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1

RX packets:22559530 errors:0 dropped:0 overruns:0 frame:0

TX packets:21337616 errors:0 dropped:0 overruns:0 carrier:0

collisions:0 txqueuelen:1000

RX bytes:28619436829 (26.6 GiB) TX bytes:3283938274 (3.0 GiB)

Interrupt:20 Memory:f2500000-f2520000

eth1 Link encap:Ethernet HWaddr c8:a0:30:ac:1d:6f


inet6 addr: fe80::caa0:30ff:feac:1d6f/64 Scope:Link





RX bytes:6572 (6.4 KiB) TX bytes:18103 (17.6 KiB)

I use the Thunar file manager to browse the device and click on START.htm to launch BeagleBone's

Getting Started page in a web browser.



Scroll down to Step #3: Browse to your board and clicking on the address of BBB's web server

192.168.7.2 opens the onboard documentation BeagleBone 101.

Also included is a link to a self-hosted instance of the Cloud9 IDE listening at 192.168.7.2:3000 that

provides a JavaScript library called BoneScript for hacking on the BeagleBone's hardware. Some tiny

example scripts are provided to blink LEDs and whatnot ... at first glance they remind me of

Arduino code but I haven't really played with this environment (or Arduino for that matter) much

yet.

Network-Manager auto-creates a second wired interface for the BeagleBone Black on my HOST ...

allowing me to ssh into the device as [email protected] or [email protected] (Angstrom runs Avahi

daemon by default) and no password. Will definitely need to change that ... but not before ...

Step 2 - Flashing updated Angstrom image

Having determined the device is working - and before diving into custom configuration - its a good

idea to flash an updated Angstrom image for the BeagleBone Black to the device's onboard eMMC

storage. This will require a microSD (8GB+) card and a 5V power adapter.

Download and unpack image



Angstrom image files for the BBB are labelled BBB-eMMC-flasher-xxxx.xx.xx.img.xz ... Latest

version as of 2 September is BBB-eMMC-flasher-2013.08.21.img.xz.

Using the above image as an example ... download the xz-utils Debian package and download and

unpack the Angstrom image ...

$ sudo apt-get install xz-utils

$ wget -c http://dominion.thruhere.net/koen/angstrom/beaglebone/BBB-eMMC-flasher-2013.08.21.img.xz

$ xz -d BBB-eMMC-flasher-2013.08.21.img.xz

Copy image to microSD

Warning

Be careful to note the proper DeviceID of your microSD card ... in my example I use sdb but your device

will probably have a different address. Command dd will completely wipe out the contents of the card. Its

not nicknamed disk destroyer for nothing!

Copy image to card using dd ...

$ sudo dd if=BBB-eMMC-flasher-2013.08.21.img of=/dev/sdb bs=1M

Flash the BBB

A USB port does not supply enough power to the BBB when flashing an image to the eMMC ... the

board must be connected to a 5V adapter. Luckily I was able to recycle an old Linksys power adapter

that provided the necessary 5V and 2000mA and fit the power plug on the BBB.

With the BBB disconnected from HOST and powered off ... insert the Angstrom-prepared microSD

card into BBB. Hold down the BOOT button (located above the microSD slot), connect the 5V

adapter, and wait until you see the bank of 4 LEDs on the BBB all light up for a few seconds before

releasing BOOT. A new image is now being flashed from card to BBB storage and will take

approximately 50-60 minutes. Upon completion all 4 LEDs will be lit solid. Disconnect power,

remove the microSD, then restore power and BBB will boot into the updated Angstrom.

Step 3 - Configuration

Root password

Root with no password oh noooooo ... set one now passwd.

You might also want to create an unprivileged user account (I did not).

Configure HOST as router

Tip from http://shallowsky.com/blog/hardware/talking-to-beaglebone.html

When BBB is connected to my HOST via USB ... Network-Manager sets up a second wired interface

eth1 to connect with BBB ... and BBB connects to HOST through usb0 ...

$ ifconfig

...

usb0 Link encap:Ethernet HWaddr BA:E1:A2:37:43:15






RX bytes:888859 (868.0 KiB) TX bytes:13309157 (12.6 MiB)

http://dominion.thruhere.net/koen/angstrom/beaglebone/

http://shallowsky.com/blog/hardware/talking-to-beaglebone.html



This arrangment is OK for getting HOST and BBB talking to each other but BBB - in lieu of an

additional ethernet cable - cannot reach the net. I created a tiny script that can be run as desired to

configure my Linux HOST to route internet traffic for the BBB ...

#!/bin/bash

# bbbIPforward.sh -- Enable internet access for my BeagleBone Black (BBB)

# using my Linux HOST as a router

bbbAddr="192.168.7.2"

hostAddr="192.168.7.1"

# Configure IP forwarding on HOST

sudo iptables -A POSTROUTING -t nat -j MASQUERADE

echo 1 | sudo tee /proc/sys/net/ipv4/ip_forward > /dev/null

# Copy ssh key to BBB for passwordless logins

ssh-copy-id root@$bbbAddr

# Configure BBB to use HOST as gateway

ssh root@$bbbAddr "/sbin/route add default gw $hostAddr"

# Backup and substitute BBB resolv.conf with HOST resolv.conf

ssh root@$bbbAddr "mv -n /etc/resolv.conf /etc/resolv.conf.bak"

scp /etc/resolv.conf root@$bbbAddr:/etc/

Date and Time

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

The BeagleBone Black does not include an onboard Real Time Clock (RTC) and thus loses its time

and date setting after every power off.

Set the time over the internet using an ntp server by first configuring the timezone linking

localtime to your proper location in zoneinfo (in my case Toronto/New York) and then running a quick

one-off command to set the proper date ...

# ln -s /usr/share/zoneinfo/America/New_York /etc/localtime

# ntpdate -u pool.ntp.org

... but the date/time will still be lost after every shutdown.

For a more permanent solution install NTP ...

# opkg update

# opkg install ntp

Find local NTP servers (Canada) and edit /etc/ntp.conf ...

driftfile /etc/ntp.drift

logfile /var/log/ntpd.log

# NTP Servers for Canada from www.pool.ntp.org

server 0.ca.pool.ntp.org




# Using local hardware clock as fallback

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



# Disable this when using ntpd -q -g -x as ntpdate or it will sync to itself

# server 127.127.1.0

# fudge 127.127.1.0 stratum 14

# Defining a default security setting

restrict 192.168.1.0 mask 255.255.255.0 nomodify notrap

Note

Angstrom uses systemd and init.d is replaced by systemctl COMMAND and files are located in

/lib/systemd/system/NAME.service.

Enable NTP services ...

# systemctl enable ntpdate.service

# systemctl enable ntpd.service

# cat /lib/systemd/system/ntpd.service

[Unit]

Description=Network Time Service

After=network.target

[Service]

Type=forking

PIDFile=/run/ntpd.pid

ExecStart=/usr/bin/ntpd -p /run/ntpd.pid

[Install]

WantedBy=multi-user.target

{% endhighlight %}

Modify ExecStart of /lib/systemd/system/ntpdate.service ....

[Unit]

Description=Network Time Service (one-shot ntpdate mode)

Before=ntpd.service

[Service]

Type=oneshot

ExecStart=/usr/bin/ntpd -q -g -x

ExecStart=/sbin/hwclock --systohc

RemainAfterExit=yes

[Install]

WantedBy=multi-user.target

Save all changes, reboot the BBB while connected to the Internet, and verify the proper date and

time are set with timedatectl ...

# timedatectl

Local time: Wed 2013-07-10 23:14:45 EDT

Universal time: Thu 2013-07-11 03:14:45 UTC

RTC time: Wed 2013-07-10 23:14:45

Timezone: America/New_York (EDT, -0400)

NTP enabled: no

NTP synchronized: yes

RTC in local TZ: no

DST active: yes

Last DST change: DST began at

Sun 2013-03-10 01:59:59 EST

Sun 2013-03-10 03:00:00 EDT



Next DST change: DST ends (the clock jumps one hour backwards) at

Sun 2013-11-03 01:59:59 EDT

Sun 2013-11-03 01:00:00 EST

Reference: What is the best way to run ntpdate?

Remote Desktop

Tip from http://digitaldiner.blogspot.ca/2013/05/quick-hint-for-beaglebone-black-user.html

In lieu of a microHDMI cable for connecting an HDMI display to the BBB the device may be

configured to transmit a remote desktop to HOST.

On BBB install the x11vnc package and launch ...

# opkg update

# opkg install x11vnc

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

... which provides a display available for remote viewing at address 192.168.7.2:5900.

On my HOST I install and use the ssvnc viewer sudo apt-get install ssvnc.

It works!

Reference: http://www.karlrunge.com/x11vnc/

Step 4 - Issues and Fixes

BeagleBone Black Rev. A5A running default Angstrom Linux

'opkg upgrade'

http://stackoverflow.com/questions/11219832/what-is-the-best-way-to-run-ntpdate-at-reboot-only-after-network-is-ready

http://digitaldiner.blogspot.ca/2013/05/quick-hint-for-beaglebone-black-user.html

http://www.karlrunge.com/x11vnc/



Fix: Do not run this command or else Bad Things Will Happen.

No login screen over HDMI

Issue: BeagleBone logo appears at boot but no login screen.

Fix: Turns out that my powered USB hub - with keyboard attached - was not being detected by the

BBB during boot. If the device thinks no keyboard or mouse is attached during boot it kills power to

the microHDMI port and hence no display. You can "wake up" the display by ssh'ing into BBB and

sending an echo 0 > /sys/class/graphics/fb0/blank command but it will still fail to detect a hot-plugged

USB keyboard or mouse.

If I connect the keyboard (with built-in trackpoint) directly to the BBB USB port and reboot and hit

SHIFT key the display springs to life and the login window appears.

Issue: BeagleBone logo appears at boot but no login screen (and this time its not the keyboard).

Fix: Creating a password for root causes the autologin task running at login screen to constantly fail

(because it doesn't know the password) and buggers up the display. To disable autologin edit

/etc/gdm/custom.conf and modify the line TimedLoginEnable from true to false ...

[daemon]

TimedLoginEnable=false

... and restart GDM with the command systemctl restart gdm.service.

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

http://bb-lcnc.blogspot.ca/2013/06/force-beaglebone-black-hdmi-resolution.html

HDMI output goes beyond edge of display

Issue: Using a microHDMI-HDMI cable to connect BBB to my 1920x1200 display produces a working

1280x720 resolution working ... but the desktop area is slightly bigger than the margins of the

display.

Fix: Needed to adjust settings on display ... modifying Image Setting->Video Mode->Video Mode to Image

Setting->Video Mode->PC Mode

Reference: http://groups.google.com/forum/#!msg/beagleboard/sxaSIUpiZo8/__TmDqD4aJcJ

drm.debug

Issue: A whole pile of these messages were filling dmesg ...

[Mon Aug 26 03:34:00 2013] [drm:output_poll_execute], [CONNECTOR:5:HDMI-A-1] status updated from 2 to 2

... repeating every few seconds.

Fix: These debugging messages can safely be turned off by editing uEnv.txt located on the mmcblk0p1

partition (not the uEnv.txt found in boot).

If that partition is not auto-mounted (mine was not) then go ahead and mount it now ...

# mount /dev/mmcblk0p1 /media/BEAGLEBONE/

... and edit /media/BEAGLEBONE/uEnv.txt by changing the line optargs=quiet drm.debug=7 to simply

optargs=quiet ... Reboot and issue resolved.

resolv.conf

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

http://bb-lcnc.blogspot.ca/2013/06/force-beaglebone-black-hdmi-resolution.html

http://groups.google.com/forum/#!msg/beagleboard/sxaSIUpiZo8/__TmDqD4aJcJ



Issue: Noticed an instance where after running opkg update internet access was broken and I was

getting a pile of wget: bad address 'feeds.angstrom-distribution.org' errors ... ifconfig showed I still had a

good connection to LAN.

Fix: Discovered that resolv.conf was pointing to 127.0.0.1. Modified file to my router's IP address ...

ran update again and everything OK.

urxvt

Issue: Using urxvt as my terminal and ssh'ing into BBB ... some commands like htop will not run.

Fix: Copy /usr/share/terminfo/r/rxvt-unicode from HOST to the BBB and place in ~/.terminfo/r/rxvt-

unicode. Same for rxvt-unicode-256color.

Reference: https://wiki.archlinux.org/index.php/Urxvt#Remote_Hosts

SSH session hangs

Issue: SSH session sometimes hangs when rebooting the BBB.

Fix: Type ~. and it should kill the SSH session.

Step 5 - Helpful Resources

Purchase a BeagleBone Black: in my hometown (Toronto) from Creatron or online from

Adafruit , Digikey and others

BeagleBone Black wiki and forum and System Reference Manual

BBB on the Embedded Linux Wiki and eewiki

Hardware tutorials on Adafruit

Excellent series of tutorials and videos by Derek Molloy ... his tables for the BBB's P8 and P9

header pins are essential if you play with the hardware

Bonescript scripting tools

Angstrom Linux package browser

BBB and the 3.8 kernel and an introduction from Jason Kridner, co-founder of BeagleBoard.org

More • beaglebone • electronics • angstrom • linux

OlderNecessary Items Acquired and the Journey Begins

Newer BeagleBone Black: 'Say Hello to My Little LEDs'

Copyright © 2014 and CC BY-NC-SA License by Daniel Wayne Armstrong Find me at daniel at circu idipity dot com

Don't miss a thing... updates by RSS and Twitter

https://wiki.archlinux.org/index.php/Urxvt#Remote_Hosts

http://www.creatroninc.com/

https://www.adafruit.com/category/75

http://www.digikey.ca/product-detail/en/BB-BBLK-000/BB-BBLK-000-ND/3884456

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

https://groups.google.com/forum/?fromgroups#!forum/beagleboard

https://github.com/CircuitCo/BeagleBone-Black/blob/master/BBB_SRM.pdf?raw=true

http://elinux.org/BeagleBone

http://eewiki.net/display/linuxonarm/BeagleBone+Black

http://learn.adafruit.com/category/beaglebone/

http://derekmolloy.ie/tag/beaglebone-black/

https://github.com/derekmolloy/boneDeviceTree/blob/master/docs/BeagleboneBlackP8HeaderTable.pdf?raw=true

https://github.com/derekmolloy/boneDeviceTree/blob/master/docs/BeagleboneBlackP8HeaderTable.pdf?raw=true

https://github.com/jadonk/bonescript

http://www.angstrom-distribution.org/repo/

http://elinux.org/BeagleBone_and_the_3.8_Kernel

http://linuxgizmos.com/introducing-the-new-beaglebone-black-kernel/

http://www.circuidipity.com/tag-beaglebone.html

http://www.circuidipity.com/tag-electronics.html

http://www.circuidipity.com/tag-angstrom.html

http://www.circuidipity.com/tag-linux.html

http://www.circuidipity.com/make-electronics-ex00.html

http://www.circuidipity.com/bbb-led.html

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Circuidipity _ Getting Started With BeagleBone Black

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