Choose CONTINUE on the title screen & enter these hiragana letters :
"shi" (6x), "ze" (2x), "nu" (2x), "wa" (16x), "a" (5x).

Incase you don't know Japanese letters : (I assume all the counts start from the upper left as 1st column & 1st row)
shi : column 2, row 3
ze : column 9, row 4
nu : column 3, row 5
wa : column 9, row 1
a : column 1, row 1