sPageDownAdvances the current row of the Control by the small page size. Stops at the last row, if the current row would move past the last row. The small page size is equal to zero and therefore has no effect if there are fewer than 200 rows in the rowset. The small page size is the number of rows divided by 100 and rounded down.
Use getSmPageSize to get the value of the small page size.
sajsset.sPageDown();
sajsset.sPageDown