<TABLE> <S> <C>


<ARTICLE> 5
<RESTATED> 
<MULTIPLIER> 1,000
       
<S>                          <C>                 <C>                 <C>                 <C>                 <C>
<PERIOD-TYPE>                12-MOS               3-MOS               6-MOS               9-MOS              12-MOS
<FISCAL-YEAR-END>                  DEC-31-1995         DEC-31-1996         DEC-31-1996         DEC-31-1996         DEC-31-1996
<PERIOD-END>                       DEC-31-1995         MAR-31-1996         JUN-30-1996         SEP-30-1996         DEC-31-1996
<CASH>                                   8,718               6,467               4,148               5,911               8,953
<SECURITIES>                            10,146              13,000              10,000              10,000              15,856
<RECEIVABLES>                            8,614               6,499               6,537               4,407               5,156
<ALLOWANCES>                               100                  92                 100                 100                 125
<INVENTORY>                              3,874               3,655               3,794               4,225               3,768
<CURRENT-ASSETS>                        32,725              31,333              26,306              26,035              35,243
<PP&E>                                   2,435               2,767               4,055               4,598               4,687
<DEPRECIATION>                           1,492               1,624               1,791               1,988               2,192
<TOTAL-ASSETS>                          54,740              54,740              57,169              52,231              50,316
<CURRENT-LIABILITIES>                    4,003               3,678               3,916               3,054               2,848
<BONDS>                                      0                   0                   0                   0                   0
<PREFERRED-MANDATORY>                        0                   0                   0                   0                   0
<PREFERRED>                                  0                   0                   0                   0                   0
<COMMON>                                42,658              42,900              43,053              39,334              37,308
<OTHER-SE>                               8,079               9,500              10,200               9,843              10,160
<TOTAL-LIABILITY-AND-EQUITY>            54,740              54,740              57,169              52,231              50,316
<SALES>                                 30,518               8,513              16,325              21,350              28,062
<TOTAL-REVENUES>                        30,518               8,513              16,325              21,350              28,062
<CGS>                                   14,485               3,909               7,804              10,448              13,739
<TOTAL-COSTS>                           14,485               3,909               7,804              10,448              13,739
<OTHER-EXPENSES>                             0                   0                   0                   0                   0
<LOSS-PROVISION>                            50                   0                   8                   8                   8
<INTEREST-EXPENSE>                           0                   0                   0                   0                   0
<INCOME-PRETAX>                          7,081               2,061               3,074               2,564               3,160
<INCOME-TAX>                             2,250                 640                 953                 800                 980
<INCOME-CONTINUING>                      4,831               1,421               2,121               1,764               2,180
<DISCONTINUED>                               0                   0                   0                   0                   0
<EXTRAORDINARY>                              0                   0                   0                   0                   0
<CHANGES>                                    0                   0                   0                   0                   0
<NET-INCOME>                             4,831               1,421               2,121               1,764               2,180
<EPS-PRIMARY>                             1.04                0.25                0.38                0.31                0.39
<EPS-DILUTED>                             0.95                0.24                0.35                0.30                0.38
        


</TABLE>