making boot.scr

How much trouble can I get myself into by trying to teach myself how
to write a boot.scr file through trial and error?

I have done some Google-ing, so I have some guidance, but I am not
100% sure as to what everything in the file means or where certain
binary addresses and args come from.

Could I end up doing major damage to my board or SD card if my
boot.scr file is written wrong?

Thank you!

This is what I have come up with:

if fatload mmc 0 0x80200000 uImage
then
setenv bootargs ' console= ttyS2,115200n8 ${optargs} mpurate=720
buddy=zippy2 vram=12M omapfb.mode=dvi:1024x768MR-16@60
omapdss.def_disp=dvi root=/dev/mmcblk0p2 rw rootfstype=ext3 rootwait'
echo ***** stand-alone demo *****
fi
bootm 0x80200000

I got 0x80200000 from "loadaddr=0x80200000" of my printenv
I made my bootargs by following the output format I received from
printenv

The worst thing that could happen is that you erase the NAND, but you're loading things from SD card anyway.

Have a look at http://gitorious.org/angstrom/openembedded/trees/org.openembedded.dev/recipes/angstrom/angstrom-uboot-scripts to see some examples of bootscripts.

regards,

Koen

That can be much shorter:

setenv dvimode ''1024x768MR-16@60"
run loaduimage
run mmcboot

See [1] for a 720p example that also sets up ram for the overlays.

regards,

Koen

http://gitorious.org/angstrom/openembedded/blobs/org.openembedded.dev/recipes/angstrom/angstrom-uboot-scripts/720p.cmd

Perfect! I got it. Thank you for your help!

I used the format:

setenv dvimode 1024x768MR-16@60
run loaduimage
run mmcboot

And followed the instructions from http://beagleintern.blogspot.com/