<ARTICLE> 5
<MULTIPLIER> 1,000
       
                                                  
<PERIOD-TYPE>                   3-MOS                   6-MOS
<FISCAL-YEAR-END>                          SEP-30-1999             SEP-30-1999
<PERIOD-START>                             JAN-01-1999             OCT-01-1998
<PERIOD-END>                               MAR-31-1999             MAR-31-1999
<CASH>                                          97,569                  97,569
<SECURITIES>                                    87,870                  87,870
<RECEIVABLES>                                   49,329                  49,329
<ALLOWANCES>                                     1,205                   1,205
<INVENTORY>                                     20,493                  20,493
<CURRENT-ASSETS>                               286,275                 286,275
<PP&E>                                         104,848                 104,848
<DEPRECIATION>                                  39,199                  39,199
<TOTAL-ASSETS>                                 440,002                 440,002
<CURRENT-LIABILITIES>                           26,542                  26,542
<BONDS>                                              0                       0
<PREFERRED-MANDATORY>                                0                       0
<PREFERRED>                                          0                       0
<COMMON>                                       337,838                 337,838
<OTHER-SE>                                      72,897                  72,897
<TOTAL-LIABILITY-AND-EQUITY>                   440,002                 440,002
<SALES>                                         66,863                 127,042
<TOTAL-REVENUES>                                66,863                 127,042
<CGS>                                           24,907                  47,868
<TOTAL-COSTS>                                   43,264                  82,809
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<LOSS-PROVISION>                                     0                       0
<INTEREST-EXPENSE>                                   0                       0
<INCOME-PRETAX>                                 26,334                  49,377
<INCOME-TAX>                                     8,689                  16,294
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<DISCONTINUED>                                       0                       0
<EXTRAORDINARY>                                      0                       0
<CHANGES>                                            0                       0
<NET-INCOME>                                    17,645                  33,083
<EPS-PRIMARY>                                     0.24                    0.44
<EPS-DILUTED>                                     0.22                    0.41