Digi 9P 9360/9750 manual Passing arguments to the kernel, Automating the image download

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L i n u x b o o t p r o c e s s

If a wrong command line parameter for "console=" is used, nothing will be displayed after "done, booting the kernel". The system may continue to boot. You may connect to the target by Telnet after telnetd is configured .

After finishing the initialization, the filesystems are mounted and the process "/sbin/init" is started with process ID 0. Init runs all applications stated in "/etc/inittab", e.g. "/etc/ init.d/rcS", the various daemons like telnetd and shells on the serial consoles.

Passing arguments to the kernel

Depending on the kernel settings, additional command line arguments may be given to the kernel. This can be modified by editing the std_bootarg environment variable. For example, to enable a console on a different serial port than the standard one when Linux boots, add 'console=ttyS1':

#setenv std_bootarg console=ttyS1

#saveenv

Automating the image download

It is also possible to automate the boot process to always boot by network when the target is reset. Adjust the environment variable "bootcmd" to contain the " run boottftp” script seen before:

#setenv bootcmd run boot_net

#saveenv

Don't forget "saveenv" to store your settings.

If you want to store a script with several commands into a variable, separate each command with a semicolon prefixed with a "\" to prevent ending the setenv command itself. (i.e. setenv MyCommand cmd1\;cmd2\;cmd3)

Updating the Flash memory

This chapter describes how you can update the U-Boot boot loader, the Linux kernel, and the root file system in the Flash memory of the module.

It is strongly recommended that you test your images before updating the Flash memory by downloading them over Ethernet using TFTP.

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L x N E T E S U s e r ’ s G u i d e

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Contents LxNETES User’s Guide ConnectCore 9P 9360/9750 Page Page Page Contents Building the First Project Interfaces & Devices Appendix B Cross-development environment IntroductionOverview Example applications Linux kernel sourcesTemplate project What’s new in LxNETES 3.2? FeaturesGeneral features RTC Gpio Conventions used in this manual This is a tip. It contains useful information about a topicAcronyms and abbreviations System requirements RequirementsSystem Requirements/Prerequisites Disk space Optional but recommended componentsApplications & Services Tftp daemonNFS server JTAG-Booster N E T E S U s e r ’ s G u i d e Introduction Connecting host PC with development boardGetting Started Minicom SeyonConnect power Seyon SettingsTest Ethernet configuration Installing LxNETES # ifconfig eth0Guided Installation Manual Installation N u a l Installation Building the First Project Building the Default ProjectRun configure Run make install Run makeAdding your own applications Application DevelopmentWriting applications Display Using C++Included example applications Proc/cpuinfo contents Debugging applications Choose the right architecture for your target Telnet daemon utelnetd Included pre-built applicationsShell applications busybox Web server BoaNano-X/microwindows Embedded QtUseful applications MemWriting kernel modules What is a kernel module?Kernel Development Writing your own kernel modulesIncluded Kernel modules Minimal Add the module to the build environmentBuilding and loading of kernel modules Modifying the default project Advanced TopicsD i f y i n g t h e d e Fault p r o j e c t Building a custom project Introduction Boot processBoot ConnectCore 9P 9360/9750 Bank # 0 00000000 32 MBLinux boot methods NAND-FlashNOR Flash USBLinux boot process MMUV a n c e d T o p i c s Updating the Flash memory Passing arguments to the kernelAutomating the image download Updating a running system the easy way Updating a running system manuallyWrite the image to Flash Download the new image file to RAMErase the Flash partition Root File System BootKernel Updating a corrupted system using a debugger Root File System Types Launch the kernel from RAM Set bootargs to be passed to the kernelDownload the kernel to RAM via Tftp JFFS2 Copy the kernel to RAM O t F i l e S y s t e m T y p e s N E T E S U s e r ’ s G u i d e Interfaces & Devices Serial interfaceSPI interface USB host interfaceI2C interface LCD interfaceSD card interface How to set the initial system date and timeCompact flash interface Real time clock RTCPCI interface Related documentation CD contentsAppendix a RelNotes.txt Install.shReadme.txt Docs ImagesConnectCore 9P 9750 CC9P9750 SetupConnectCore 9P 9360 CC9P9360 HardwareConnectCore 9P 9360 / ConnectCore 9P Memory layoutsFlash memory layout Sdram memory layoutTextbase N E T E S U s e r ’ s G u i d e Boot command reference Appendix BO o t c o m m a n d r e f e r e n c e Skipped CC9C CCXP270 UNC90 User keys Example A9M24x0