In message 001401c31955$37fdf290$904fa93d@john you wrote:
But, I built same codes in rominit.S based on Vxworks, the LED is lighting.(
The rominit.S code of VxWorks is different software, so different rules may apply. I have no idea when and where they set up a stack.
codes is following ) What's problem in u-boot? is it possible to change the IMMR address by me? Next, are there any introduction on the file of u-boot.lds or how
There is no problem in U-Boot. You are just doing things that make no sense.
And no, as long as you don;t understand why IMMR must be mapped at 0xF0000000 or above you are not permitted to change it.
to modify it according to customized board?
Please read the documentation that comes with the GNU Linker.
because it is my personal interest in u-boot, so I have no debuger as BDI on hand and only to debug the U-boot using lighting LEDs on board. Is there lower cost debuger to be ordered ?
For MPC8xx based systems there is the BDM4GDB project at sourceforge; a BDM4GDB parallel port adapter costs just 49.95 Euro.
Next, can anyone help give the used assemble codes to light LED? I'm not familiar with assemble.
Use "gcc -S" to translate your C code and try to nderstand the generated output.
Best regards,
Wolfgang Denk