Changes:
Added a transistor at output to efficiently drive the LED.
Corrections suggested by:
+Richard Gray
A lot thanks to him
When number of 1s in the binary data is odd.
It's Odd parity. This is indicated by glowing LED here.
When number of 1s in binary data is even or no 1s (all zeros).
It's Even parity. This is indicated by Off LED here.
Parity indicators are used in communication system.
