You can approximate a square wave using sine waves and a bit of math. Just research fourier transformation.
Morning has broken like the first morning
Blackbird has spoken like the first bird
Praise for the singing
Praise for the morning
Praise for them springing fresh from the world
Sweet the rain's new fall, sunlit from heaven
Like the first dew fall on the first grass
Praise for the sweetness of the wet garden
Sprung in completeness where his feet pass
Mine is the sunlight
Mine is the morning
Born of the one light Eden saw play
Praise with elation, praise every morning
God's recreation of the new day
Morning has broken like the first morning
Blackbird has spoken like the first bird
Praise for the singing
Praise for the morning
Praise for them springing fresh from the world
