good Embedded C resources plz...


This is christina.Just graduated out of the school.I wanna learn C
programming language to the level that I can do good embedded

Can anybody plz give me some resources/books/pointers?

In my course I have learnt basics like arrays,pointers,data
structures.But in embedded field I see,more usage of macros,data type
casts,volatile variables etc.
I am having tough time to overcome these embedded C hurdles.If someone
give some direction,I will be very thankful.

I wanna be strong at embedded C programming.

Thank you for your kind support.