Too bad it's not for an HCS12 or AVR. I could answer questions on those easier. We cannot bend the rules (ie. do your work for you), but we can answer specific questions you have.
Do you have a textbook? My university's library has a fairly good selection of books, so you might check for a book on the PIC16 microcontrollers. Any microcontroller book that goes over assembly could give you an idea of what to do, but you'd probably run into syntax issues and differences in mnemonics, registers, and so forth. A PIC book would be best, but I think AVR's might be the easiest to compare with. A book similar to this one would probably help:
http://www.amazon.com/Designing-Embe...QYJ6ATJAVJQFHA
I know there are others, but I mainly use the HCS12 and AVR microcontrollers for classes and projects.
Definitely get the datasheet for your specific chip. It will have information on timers, PWM channels, the USART(s) and some information about the instruction set (so you can get the mnemonics right). The datasheet may have enough information for you to at least do the flowchart and an attempt at the code.
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