[U-Boot] vxWorks and U-boot

Hi.

I'm trying to use an evaluation board with U-boot to load and run a vxworks6.8 image for PPC CPU. I'm using TFTP to download the image to address 0x100000. After that I tried several ways to start running the image, and failed in every way. I tried bootvx, bootelf, and several other ways. In all cases I got a machine exception error, and the board restarted.

What can be the cuases for that? Can it be thatt he image is too big? I have 256MB of RAM on the board, and the image is 23MB.

Or maybe I'm doing something wrong?

Thanks, Ofer