<TABLE> <S> <C>

<PAGE>
<ARTICLE> 5
<RESTATED>
<MULTIPLIER> 1,000

<S>                             <C>                <C>                <C>                <C>                <C>
<PERIOD-TYPE>                   YEAR               YEAR               3-MOS              6-MOS              9-MOS
<FISCAL-YEAR-END>                     DEC-31-1995         DEC-31-1996        DEC-31-1996        DEC-31-1996        DEC-31-1996
<PERIOD-START>                        JAN-01-1995         JAN-01-1996        JAN-01-1996        JAN-01-1996        JAN-01-1996
<PERIOD-END>                          DEC-31-1995         DEC-31-1996        MAR-31-1996        JUN-30-1996        SEP-30-1996
<CASH>                                      12771                7208               8684               6706               7053
<SECURITIES>                                    0                5931               3936               5918               5993
<RECEIVABLES>                                7510               10261               7727               8735               8882
<ALLOWANCES>                                    0                   0                  0                  0                  0
<INVENTORY>                                  3145                3197               3076               3715               3013
<CURRENT-ASSETS>                            23880               27617              23936              25591              25823
<PP&E>                                       2212                2491               2295               2255               2456
<DEPRECIATION>                                  0                   0                  0                  0                  0
<TOTAL-ASSETS>                              26846               30829              26949              28506              28991
<CURRENT-LIABILITIES>                        8124                8202               7592               8202               7649
<BONDS>                                        68                  15                 55                 38                 29
<PREFERRED-MANDATORY>                           0                   0                  0                  0                  0
<PREFERRED>                                     0                   0                  0                  0                  0
<COMMON>                                    25655               26068              25658              25674              25789
<OTHER-SE>                                 (7001)              (3461)             (6356)             (5408)             (4476)
<TOTAL-LIABILITY-AND-EQUITY>                26846               30824              26949              28506              28991
<SALES>                                     31039               38662               8704               9750               9711
<TOTAL-REVENUES>                            31039               38662               8704               9750               9711
<CGS>                                        9530               10793               2557               2806               2610
<TOTAL-COSTS>                               19596               23130               5254               5716               5850
<OTHER-EXPENSES>                             (76)               (601)              (153)              (139)              (151)
<LOSS-PROVISION>                                0                   0                  0                  0                  0
<INTEREST-EXPENSE>                            230                  42                 14                 12                  9
<INCOME-PRETAX>                              1759                5298               1032               1355               1393
<INCOME-TAX>                                  305                1582                330                359                426
<INCOME-CONTINUING>                          1454                3716                702                996                967
<DISCONTINUED>                                  0                   0                  0                  0                  0
<EXTRAORDINARY>                                 0                   0                  0                  0                  0
<CHANGES>                                       0                   0                  0                  0                  0
<NET-INCOME>                                 1454                3716                702                996                967
<EPS-PRIMARY>                                 .94<F1>             .57<F1>            .11<F1>            .15<F1>            .15<F1>
<EPS-DILUTED>                                 .27<F1>             .52<F1>            .10<F1>            .14<F1>            .14<F1>
<FN>
<F1>The adoption in fourth quarter 1997 of FAS 128, a new standard of computing
and presenting both basic and diluted net income per share.
</FN>


</TABLE>