Pragmatic Embedded Linux



This document is a brief guide to creating a Pragmatux Workstation development environment, and a Pragmatux Device filesystem image, for the Beagleboard Revision C (or later) hardware.

Additional Pragmatux documentation is available at the Pragmatux website. Additional Beagleboard documentation is available at the Beagleboard website.

Some terminology

Pragmatux Workstation

The base environment for creating programs, packages, and filesystem images for an embedded system; hosts development tools like cross-compilers, editors, and package creators that are not normally needed by or installed on an embedded system. Often referred to as simply "the workstation".

Pragmatux Device

The embedded system itself; often referred to as "the device", or "the target device". Pragmatux devices typically do not host cross-compilers or other development tools.

Prep a Debian Workstation

Pragmatux uses the Debian Operating System Version 8, a.k.a. "jessie", as its foundation. The amd64 workstation architecture is routinely tested, in both native and chroot environments. Other configurations may also work.

Install Debian as the native OS on an amd64-based PC workstation, inside a virtual machine, or as a chroot under another operating system. (TODO: minor tweak required by guestfish if in schroot.)

Add the Pragmatux Workstation Repository

Pragmatux provides a single package file containing the APT sources required by Pragmatux: apt-sources-ptux-sdk.deb.

Download apt-sources-ptux-sdk.deb, and install it on your Debian workstation.

$ wget
$ sudo dpkg --install apt-sources-ptux-sdk.deb

Add the instruction set architectures for target devices. The package manager requires this to be a manual step:

$ sudo dpkg --add-architecture armel
$ sudo dpkg --add-architecture armhf

Update the workstation’s package repository database:

$ sudo apt-get update

Your workstation is now a generic, "Pragmatux Workstation".

Install the Beagleboard SDK

$ sudo apt-get install --no-install-recommends ptux-sdk-beagleboard

Answer "yes" to the prompts. Your workstation is now ready to create Beagleboard-hosted applications and filesystem images.

Create a Device Filesystem Image

The following command composes a generic Pragmatux Device filesystem. Additional packages can be added later by invoking apt-get at the device command line. The Pragmatux documentation describes how to add packages to the default configuration, and how to create a customized default of your own.

$ fakeroot mkos-beagleboard

The above step should take less than a minute. The target’s filesystem image is the file ptux.img.

Create a Bootable SD Card

Attach an SD card to your workstation. Replace /dev/sdcard with the name of the device node actually assigned by your workstation, i.e. /dev/sdh. Use the dmesg command, if necessary, to verify that you have the correct device node.

The SD card must be 1GB or larger in capacity.

the following command will erase the ENTIRE contents of whatever device you specify. Be absolutely certain you have the right value before proceeding!
$ sudo dd if=ptux.img of=/dev/sdcard bs=1M

Resize the SD Card Filesystem (optional)

If your SD card is larger than 1GB, you can resize the filesystem to take advantage of the additional space. You can perform this step at any time, but large or "slow" SD cards will take a VERY long time to resize.

In the following, replace /dev/sdcard-partition-2 with the actual device node assigned by your workstation for the card’s second primary partition, i.e. /dev/sdh2.

$ sudo fsck -f /dev/sdcard
$ sudo fdisk /dev/sdcard
(TODO: commands to delete the partition)
(TODO: commands to create larger partition starting at the same cylinder)
$ sudo resize2fs /dev/sdcard-partition-2

Attach a Serial Console (optional)

If you have a serial cable for your Beagleboard, attach it now. Pragmatux redirects the kernel console to the Beagleboard’s P9 header, at 115200N81. See the Beagleboard’s reference manual for more information.

Boot to Pragmatux for the First Time

Insert the SD card into the Beagleboard’s connector, and hold down the USER button when powering up the device. Over the next two or three minutes, the final installation steps for Pragmatux will take place automatically on the device itself.

Once the device reboots, it is a complete, fully-operational, Pragmatux Device. Congratulations!

Log into the Device (optional)

The serial console’s default username is root, and the password is password.

If you have attached the Beagleboard to an ethernet adapter, and your network supports DHCP, then you can also use SSH to log into the device.

Pragmatux 3.0 device ttyO2

device login: root
Password: password


Configure IP/ethernet (optional)

Pragmatux devices use the network manager conman for IP address assignment via DHCP. They also provide the ip command for manual network interface configuration and review.

If an ethernet cable is connected at startup, then the device will obtain its own, unique IP address via DHCP. To discover that address from the device’s command line, use the following command:

root@device:~# ip addr show eth0
eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000
    link/ether 00:0c:29:c3:51:05 brd ff:ff:ff:ff:ff:ff
    inet brd scope global eth0
    inet6 fe80::20c:29ff:fec3:5105/64 scope link
    valid_lft forever preferred_lft forever

The line beginning with inet is the device’s IPv4 information.

To manually set the IP address to

root@device:~#  ip addr replace dev eth0

See the ip(8) manpage for more information.

Enjoy your new workstation and device!

The Pragmatux Foundation thanks you for choosing our Debian-based approach to embedded Linux.