S-Video ? C4 angstrom

How do I enable s-video on the beagleboard rev C4?

I've read that you can set it using the boot args "omapdss.def_disp=tv
omapfb.mode=tv:ntsc" but how do I go about doing that? What exactly
would I type in minicom and is there an easier way to do this in
angstrom?

Thank you for your time.

I'd like to amend the above to say I did get it working, with a few
problems:

1) screen was flickering, added "omapdss.tvcable=composite" because
I'm using a s-video to coaxial adapter. fixed the problem.

2) odd fuzziness don't know if this is my fault for missing something

My procedure:
..
mmc init

fatload mmc 0 0x80200000 uImage

setenv bootargs "console=ttyS2,115200n8 root=/dev/mmcblk0p2 rw
rootfstype=ext3 rootwait omapfb.mode=tv:ntsc omapdss.def_disp=tv
omapdss.tvcable=composite"

bootm 0x80200000

Did I do this correctly? .