voltage inverter - an easy one?

I'm trying to trigger a 555, but only have -V available as trigger. Is there an easy solution to invert my trigger voltage? Existing trigger voltage is 0 to -2V, supply voltage is 12V. Thanks!!!!

dc dc converter

sorry, should have posted as a converter rather than inverter. sorry for lack of any essential info req'd for help. appreciate the help!

See my reply in the Electronic Projects Design/Ideas/Reviews section:

https://www.electro-tech-online.com/threads/garage-door-opener-question.2126/

Ron