Bootloader (U-Boot); Boot Loader Toolchain - WAGO 750 Series Manual

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Bootloader (U-Boot)

Boot Loader Toolchain

9 Bootloader (U-Boot)
U-Boot and the Linux kernel boot up process are controlled via environment
variables within the boot loader that are stored in the last sector of the flash
memory. These variables are verified by a CRC32 checksum. The
environment variables can be changed via the boot loader, the web server or
through an example application in Linux. To use the boot loader, you have to
enter a password during start-up of the Linux fieldbus coupler which will then
give access to the configuration interface (see chapter 5.10.2). The
environment variable can now be displayed using
LFBK # printenv
or be changed:
LFBK # setenv <variablenname> <variablenwert>
There is no equal sign between variable name and variable value. All changes
that are made are not permanent and are lost when the Linux fieldbus coupler
is rebooted. Use the
flash memory.
LFBK # saveenv
Saving Environment to Flash...
LFBK #
A list of all possible Shell commands can be viewed using
Help
9.1 Boot Loader Toolchain
The boot loader requires a special toolchain which is called "DENX
Embedded Linux Development Kit" (ELDK). A pre-compiled version for x86
host systems is available under: ftp://ftp.leo.org/pub/eldk/2.1.0/eldk-arm-
linux-x86/ or on the WAGO distribution CD-ROM under
CD:/toolchain/uboot/.
You install the toolchain and the other utility programs in the super user mode
with the following command:
> rpm -i gcc-arm-2.95.4-4j_3.i386.rpm
4j_3.i386.rpm
binutils-doc-2.11.93.0.2-3b_2.i386.rpm
4j_3.i386.rpm
call, in order to get permanent changes in the
saveenv
binutils-arm-2.11.93.0.2-3b_2.i386.rpm
gcc-doc-2.95.4-
cpp-arm-2.95.4-
WAGO-I/O-SYSTEM 750
Linux Fieldbus Coupler