[ltp] Horizontal interrupt

[linux-thinkpad@linux-thinkpad.org]

Does anyone know of a way to pick up the start of the horizontal sweep.
Another way to say this is to read or generate an interrupt at the start of the speep(how?).
I know that I could pick this off of the vga connector in the back but I would really like to find a cleaner, nicer way.

I regularly program in both assembler and C so even if it meant some kernel hacking this
 would be ok.
Thanks,
  Bert