How to transmit ASCII over RS-232?
So I dug a little bit for you. Take a look at Freescale's "HCS08 Peripheral Module
Quick Reference"which is linked from the product page. There is a section titled "Using the Serial Communications Interface (SCI) for the HCS08 Family Microcontrollers." And Subsection 2 of that section is titled "Code Example and Explanation." Follow the bouncing ball and that should get you going. The Dev board already has the circuits needed to go from TTL UART to RS232. There's also code examples in there for the ADC. You'll then just need to manage converting your ADC readings into ASCII using "the usual methods" like, for example, sprintf from stdio.h.

Half the battle with acclimating yourself to a new controller/processor is figuring out where the examples and support ecosystem reside. Hope this helps. P.S. The code examples zip file referenced in the Quick Reference is here (not the easiest thing to find).