PIC32mx UART scrambled text
putcUART1(data);            // Transmit 'data' through UART


The "data" will be put out in binary aka "scrambled signs". On the terminal you'll likely want hex or decimal chars: You need to convert the data first.

putcUART1('13');            // Transmit '13' (carriage return)


The code does not match the comment. BTW: This should generate a compiler warning about a multi-character constant. Correct this to:

putcUART1(13);


This will output a CR. 

I recommend reading a book about the C programming language. Then you will understand much better what happened and why.