Hello,
If you look through the 16-bit board you will see a lot of discussion on the SCI and how to use the Terminal.
You will also be able to find pieces of software you can plug into your EVB.
SCI modules of the S12X are able to work as UART. The only thing is that a computer serial port is about 12V and not 3-5V, so you need to translate the level.
But once again, all this info is available in previous posts.
I can also advise you CodeWarrior boards for the use of the printf in embedded. There is more than one long thread about options and members who posted their worries and solutions.
USB multilink is a single wire debugger but is not a "serial port" as I believe you mean it.
FlexRay protocol is not that easy and you will need to read documentation. You cannot improvise on FlexRay.
Regards,
Alban.