If you are weak at programming, you need to get familiar fast. Programming embedded systems is probably an order of magnitude harder than programming PCs. There are NO shortcuts. YOU have to do everything. There is NO operating system to help out.

Use a high level language for everything, unless you run into severe speed problems somewhere. Then optimise the slow bits with assembler. You can (carefully) wangle existing 'C' codes into what you want, though the possibility of using good old Intel 8052 BASIC should not be ignored.

Sorry, there are no easy solutions.

Steve