St. Benedict Medallion

This is the back of a St. Benedict Medallion - the same medallion appears in the proper crucifix used when performing the Roman Rite of Exorcism (rarely done in modern times but still occur!).
What do the jumble of letters mean, you may ask? Here it is, taken from my Catholic Edition Douay-Rheims Bible from St. Benedict Press.

At the top...
PAX = Peace.

In the circles around the cross...
CSPB: Latin: Crux Sancti Patris Benedicti.
English: The Cross of our Holy Father Benedict.


On the cross itself...
CSSMI-NDSMD: Latin: Crux sacra sit mihi lux! Ne draco sit mihi dux!
English: May the holy cross be my light! May the dragon never be my guide!


Surrounding the cross...
VRSNSMV-SMQLIVB: Latin: Vade retro Satana! Numquam suade mihi vana! Sunt mala quae libas. Ipse venenum bibas! 
English: Begone Satan! Never tempt me with your vanities! What you offer me is evil. Drink the poison yourself!