Original firmware upgrade after patched firmware?

i have sohw 1693s model dvd writer, i upgraded it with a patched firmware and now i cant use original firmwares, how can i use them again?

get “KS0B - patched - crossflashing” here: http://codeguys.rpc1.org/firmwares.html#SOHW-1693S

thank you

U can use Flashfix