Decided to try mining grin with Grinmint. I am CPU mining at almost 0.1 GPS. How long will it take to get 1 share at difficulty 1?

EDIT: Took about 15 minutes…

How is the difficulty convert into target in grin? Never understood this really well in bitcoin, even after reading Andreas book on this because difficulty bits in a block is in hexadecimal but when difficulty is given in decimal is confusing to me. I know that target = coefficient * 256**(exponent - 3) , where exponent is the first 2 hexadecimal digits of difficulty bits and the coefficient are the other hexadecimal digits (all this for bitcoin).

Can someone explain what difficulty in decimal means (in grin)?