While fighting in a single player battle, press Up(2), Down(2), Left, Right, Left, Right, B, A, A sound will confirm correct code entry. This will allows you to pull off special moves with easy movements. Fir example, as Ryu press Forward + Punch for the Fireball, and the Fireball move now does the Dragon punch. This makes the game much easier to play with the small D-pad. Press Select to toggle "Easy special mode" on or off.
Gouki
Accumulate 5000 points.
In game-reset
Press Select + Start.
Secret modes
Play single player mode to unlock secret modes such as survival and time attack.