How to see where I am picking now

Detach the serial cable from your serial output pin.
Attach an LED to the serial output pin with 220 ohm resistor through PIC.
Notice how the LED blinks when you are sending serial messages.
This can be an excellent way to test to make sure your chip is properly sending serial data out.

'Create frame animation 0-255, and send the data to computer, I can see the frame one by one.