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Step-by-Step Guide to your own Linux Application
File System and Linux Kernel Update
WAGO-I/O-SYSTEM
750
Linux Fieldbus Coupler
5.10.2 TFTP Client Setup
File system changes can also be done directly in Linux, however, it is not
possible to replace the entire file system at the same time. An update
exclusively of the Linux kernel or exclusively of the file system is only
possible via the TFTP client of the boot loader (U-Boot).
To have access to the boot loader configuration interface, turn the selector
switch to the upper position, connect the communication cable to the
configuration interface of the Linux coupler, start the console program, e.g.
minicom, and switch on the voltage of the Linux fieldbus coupler.
When the following is output:
I2C-EEPROM detected.
I2C-RTC detected.
In: serial
Out: serial
Err: serial
Booting in 3 seconds - enter abort password to prevent this
you have to enter the password
geheim
(on the serial console) to abort the
boot loader boot process and to change to the U-Boot environment. The boot
loader switches to its shell environment. If after three seconds the password
has not been entered, the boot loader loads the Linux kernel.
The
printenv
command outputs the environment
variables:
LFBK # printenv
bootargs=root=/dev/mtdblock3 rw mem=16769120
bootdelay=3
baudrate=38400
ipaddr=192.168.1.3
netmask=255.255.255.0
update-rootfs=tf 0x40000 jffs2.img;protect off 01:11-51;era
01:11-51;cp.b 0x40000 0x20040000 $(filesize)
update-kernel=tf 0x40000 linux.flashme;protect off 01:52-69;era
01:52-69;cp.b 0x40000 0x202d0000 $(filesize)
update-ub=tf 0x40000 ub.bin;protect off 01:08-9;era 01:08-
9;cp.b 0x40000 0x20010000 $(filesize)
bootA=setenv bootargs $(bootargs) wago_console=yes ip=$(ipmode)
$(output);bootm
bootB=setenv bootargs $(bootargs) ip=$(ipmode) $(output);bootm