it might be a code for a game like gta san andreas
up up down down left right left right b a SELECT start
Up = Up Down = Down Left = Left Right = Right Z = A X = B A = L S = R Enter = Start Backspace = Select
If it's visual boy, default is as following z=a x=b up=up down=down left=left right=right back=select enter=start
The Contra Code, also known as the Konami Code, is used in most konami games, and is Up,up,down,down,left,right,left,right,B,A, then start or select, depending on what game it is. for Contra, It would be start
Sonic The Hedgehog: After it says Sonic Team Presents, at the start of the game, Press: Up, Down, Left, Right, Y + Start and you can choose any level. Sonic 2:There is none. Sonic The Hedgehog 3:At the drum beat hurry and press up up down down up up up.Go down twice and you will see sound test. Sonic and Knuckles: Start Mushroom Hill Zone as Sonic. Head right until you come to the first Pull-Up machine. Jump and hang on it. Then, Press Left, Left, LEFT RIGHT RIGHT RIGHT UP UP UP then get a game over at where you select sonic or knuckles hold Y+START THEN CHOOSE A LEVEL (THE NUMBERS ARE SONIC TAILS AND KNUCKLES) That's how you go to Level Select in Sonic Classic Collection. (Note: If I got some thing not right improve my answer)
up up down down left right left right a b select start
left, right, left, right, up, down, up, down, a, b, start, select
Left left right right up up down down select start
up up down down left right left right a b select start
up up down down left left right right ab start select
up up down down left right left right b a SELECT start
for stage select up down left right hold the buttons and press start for debug mode press up a down a left a right a
"up up down down left right left right b a select start" have to type everything in quotation marks including spaces
Up down left right select start There you go all characters unlocked
Up = Up Down = Down Left = Left Right = Right Z = A X = B A = L S = R Enter = Start Backspace = Select
press start-select-left-right (L,R) press start-select-left-right (L,R)
The Contra Code, also known as the Konami Code, is used in most konami games, and is Up,up,down,down,left,right,left,right,B,A, then start or select, depending on what game it is. for Contra, It would be start