EM-X270: Linux: Getting started

Image installation

Installation with LiveDisk

• Extract the contents of LiveDisk.zip from Linux package for EM-X270 onto USB flash drive formatted with FAT filesystem.
• Insert the flash drive into "USB-A to mini-USB" adaptor supplied with EvalKit, and connect the other side of the adaptor to EM-X270.
• Power up the EM-X270 while holding the "suspend/resume" button. You may release the button as soon as you see CompuLab logo on the LCD screen.
• Wait until systems starts. You will be asked to calibrate the touchscreen and create a user to log in to the system
• Click on the Updater icon. EM-X270 updater application will start.

  

• Click Forward to continue, or Cancel if you decided to abandon the installation

  

• By default, updater application will search for /media/usb/em_x270.img image file. Press Open or fill the filename entry to choose another image.
• After you've chosen the image, press Forward.

  

• Press Start! button to update EM-X270.

  

Make sure you do not interrupt the updater application after pressing Start!, keep the USB flash drive inserted and the device powered up during the update process.

Any time you would like to boot clean system from the USB flash drive, you can unpack the original LiveDisk.zip to the USB flash drive and start over.

• Proceed to After installation and restart section.

Installation using NFS

• Follow the steps in Networked Root Filesystem Guide
• Make sure to power off the EM-X270
• Connect EM-X270's ETH0 port to your local Ethernet
• Connect your host PC to the EM-X270 via a null modem cable supplied with the Eval Kit.
• Start terminal emulation software on your PC using the COM port to which the null modem is connected and configure it as described in EM-X270's U-Boot documentation.
• Power up the EM-X270. U-Boot will start and you will get the command prompt in your terminal program.

If the boot settings of your EM-X270 are set to load the operating system, you may need to press and hold ^C while turning the EM-X270 on, in order to get command prompt.

• You can use U-boot dhcp command to obtain IP address or manually set ipaddr and serverip environment variables:

> setenv serverip <host ip address>
> setenv ipaddr <EM-X270 ip address>
> saveenv

• Next environment settings are passed to Linux Kernel and are needed for NFS root:

> setenv bootargs "root=/dev/nfs nfsroot=<your host ip>:/path/to/rootfs console=ttyS0,115200 ip=dhcp"

If boot_mode environment variable is set to linux or wince, then it should be changed to install and bootcmd variable should be unset, so U-Boot will not override the bootargs variable.

• Use the following U-boot command to boot Linux on EM-X270:

> tftp a0100000 uImage && bootm

• After the image is loaded you will get Linux login prompt. Login as root into the system.
• Copy the kernel and Angstrom jffs2 files from em_x270.img (ext2 image inside LiveDisk.zip) to USB stick or NFS share, so you can access them from EM-X270.
• Now you can install kernel and filesystem images to the NAND flash either from USB stick or NFS share using standart Linux MTD utilities (flash_eraseall, nandwrite).
• Proceed to After installation and restart section.

After installation and restart

• After the installation proccess completed successfully, U-Boot on EM-X270 needs the following environment variables set prior to booting from NAND flash:

> setenv boot_angstrom "setenv bootargs root=/dev/mtdblock5 rw rootfstype=jffs2 console=ttyS0,115200; fsload a0100000 uImage && bootm;"
> setenv boot_mode linux
> setenv nand_mode on
> saveenv

• Now you can reset the EM-X270 and it will boot Angstrom Linux from the internal NAND flash. Note, that the first boot takes relatively much time because Angstrom Linux performs a lot of one-time initialization tasks.

See also

• Angstrom Linux for EM-X270
• Linux Development for XScale modules