Gradius (NES)

The NES version of Gradius introduced the famous "Konami Code": Up, Up, Down, Down, Left, Right, Left, Right, B, A. The world would never be the same.

PRG CRC Test
Hold A + B, then power on the game to access this test. "KONAMI ONE" will be displayed if the PRG CRC matches the internal value, otherwise "KONAMI TEN" will be displayed.

The same method is used with the CHR data integrity status to show "GRADIUS ONE" or "GRADIUS TEN".

Build Date
At the beginning of the PRG ROM is the string RC810 1,0 860219 (Version 1.0, compiled February 19, 1986).