Fit piecrust into a 9-inch pieplate according to package directions; fold edges under, and crimp.
Combine sugar and cornmeal in a large bowl. Stir in eggs and buttermilk until combined. Stir in pineapple and next 5 ingredients. Pour filling into piecrust.
Bake at 350° for 45 minutes or until pie is set and top is lightly brown. Serve warm, at room temperature, or cover and chill until ready to serve.