Transfer data on a 3.3V high speed UART (> 20 MBaud) to a PC terminal application?
There are a few ways, first you need to find out the logic levels of the output of the micro controller. Most microcontollers use 3.3V logic levels (TTL or CMOS, and this determines how a 1 or 0 is transmitted)
I think the easiest way to get data out of a microcontroller is to use a USB to UART converter like the FT232RQ (or equivalent), which can be purchased at many hobbyist electronic distributors like adafruit or sparkfun.
These convert logic level serial to USB (it shows up as a serial port, you can then read the data with any program that can talk to serial like realterm, c , python, matlab ect)

Source: http://www.datasheetdir.com/Usb-To-Rs232-Uart-Serial-Converter-Pcb%2BApplication-Notes
You don't need the RTS and CTS lines (but they are better for flow control if you need more accurate data), you'd only need the RX line connected to the tx line on your microprocessor.
Another thing that I've done is a virtual com port with usb to the processor, but most micros only support 'regular' USB speed which is 12Mbps.