Trying to setup my keyboard back lighting?

Trying to setup my keyboard back lighting?

So I setup Ubuntu to stop setting my screen brightness to full using this
script and making it a startup program.
*#!/bin/bash
myBrightness=9; currentBrightness=cat
/sys/class/backlight/acpi_video0/brightness; count=$(( $currentBrightness
- $myBrightness )) ; while [ $count -gt 0 ] do xdotool key
XF86MonBrightnessDown let count=$(($count-1)); done*
anyway, I want to do the same for my keyboard back-lighting but I can not
seem to find the files I need to make this work. Where would the files for
the keyboard back light be?