<PAGE>   1
                                                                     Exhibit 4.1











                            STOCK PURCHASE AGREEMENT

                                      among

                              DIMATECH CORPORATION,

                                HIROYUKI KATAOKA

                                       AND

                                NETSILICON, INC.



                          Dated as of February 16, 2001
<PAGE>   2
                                TABLE OF CONTENTS
                                                                           Page

ARTICLE I....................................................................1

DEFINITIONS..................................................................1
   1.01.  Definitions........................................................1

ARTICLE II...................................................................2

PURCHASE AND SALE............................................................2
   2.01.  Purchase and Sale..................................................2
   2.02.  Closing............................................................3

ARTICLE III..................................................................3

REPRESENTATIONS AND WARRANTIES OF SELLER.....................................3
   3.01.  Corporate Existence and Power......................................3
   3.02.  Corporate Authorization............................................3
   3.03.  Governmental Authorization; Consents...............................3
   3.04.  Non-Contravention..................................................4
   3.05.  Capitalization.....................................................4
   3.06.  Subsidiaries.......................................................4
   3.07.  Financial Statements...............................................4
   3.08.  Absence of Certain Changes.........................................5
   3.09.  Property and Equipment.............................................6
   3.10.  No Undisclosed Material Liabilities................................6
   3.11.  Litigation.........................................................7
   3.12.  Material Contracts.................................................7
   3.13.  Insurance Coverage.................................................8
   3.14.  Compliance with Laws; No Defaults..................................8
   3.15.  Finders, Fees......................................................8
   3.16.  Intellectual Property..............................................8
   3.17.  Inventories........................................................9
   3.18.  Receivables........................................................9
   3.19.  Taxes..............................................................10
   3.20.  Employees..........................................................10
   3.21.  Employee Benefit Plans.............................................11
   3.22.  Customers and Suppliers............................................11
   3.23.  Products...........................................................11
   3.24.   Transactions with Affiliates......................................12
   3.25.  Other Information..................................................12

ARTICLE IV...................................................................12

ADDITIONAL REPRESENTATIONS AND WARRANTIES OF SELLER..........................12
   4.01.  Title to and Validity of Shares....................................12
   4.02.  Authority..........................................................12

ARTICLE V....................................................................12

REPRESENTATIONS AND WARRANTIES OF BUYER......................................12
   5.01.  Organization and Existence.........................................12
   5.02.  Corporate Authorization............................................13
   5.03.  Governmental Authorization.........................................13
   5.04.  Non-Contravention..................................................13
   5.05.  Finders' Fees......................................................13
   5.06.  Litigation.........................................................13
   5.07.  Compliance with Laws; No Defaults..................................13
   5.08.   Transactions with Affiliates......................................14
<PAGE>   3
ARTICLE VI...................................................................14

COVENANTS....................................................................14
   6.01.  Resignations.......................................................14
   6.02.  Further Assurances.................................................14
   6.03.  Public Announcements...............................................14

ARTICLE VII..................................................................14

CONDITIONS TO CLOSING........................................................14
   7.01.  Conditions to the Obligations of Each Party........................14
   7.02.  Conditions to Obligations of NETsilicon............................15
   7.03.  Conditions to Obligation of Seller.................................15

ARTICLE VIII.................................................................16

INDEMNIFICATION..............................................................16
   8.01.   Indemnification Relating to Agreement.............................16
   8.02.   Third Party Claims................................................16
   8.03.   Tax Contests......................................................17
   8.04.   Limitations.......................................................17
   8.05.   Time Limit........................................................17
   8.06.   Post-Closing Dimatech Operations..................................17

ARTICLE IX...................................................................18

MISCELLANEOUS................................................................18
   9.01.  Notices............................................................18
   9.02.  Amendments; No Waivers.............................................18
   9.03.  Expenses...........................................................19
   9.04.  Successors and Assigns.............................................19
   9.05.  Further Assurances.................................................19
   9.06.  Governing Law......................................................19
   9.07.  Counterparts; Effectiveness........................................19
   9.08.  Entire Agreement...................................................19
   9.09.  Knowledge..........................................................19
   9.10.  Captions...........................................................20

Schedules

Schedule 2.01 List of Stockholders
Schedule 3.03 Required Consents
Schedule 3.08 Changes Since Balance Sheet Date
Schedule 3.12 Material Contracts
Schedule 3.14 Permits
Schedule 3.16 Intellectual Property
Schedule 3.19 Taxes
Schedule 3.20 Employees
Schedule 3.21 Employee Benefit Plans
Schedule 3.24 Transactions with Affiliates
<PAGE>   4
                             INDEX OF DEFINED TERMS


<TABLE>
<S>                                                 <C>
Affiliate                                           1

Balance Sheet Date                                  1

Closing                                             3
Closing Date                                        1
Common Stock                                        1

Dimatech                                            1
Dimatech Securities                                 4
Dimatech's Proprietary Rights                       1

Employee                                            1

Financial Statements                                4

Indemnifiable Amounts                              16

knowledge                                          19

Lien                                                1

Material Adverse Change                             1
Material Adverse Effect                             1

NETsilicon                                          1
NETsilicon's Counsel                                2

Permit                                              8
Person                                              2
Plan                                               11
Plans                                              11
Proprietary Rights                                  2

Required Consents                                   4

Sellers                                             1
Seller's Counsel                                    2
Shares                                              1
Subsidiary                                          2

Tax                                                10
Tax Return                                         10
Tax Returns                                        10
Taxes                                              10
Threshold Amount                                   17

Unaudited Balance Sheet                             4
</TABLE>
<PAGE>   5
                            STOCK PURCHASE AGREEMENT

      AGREEMENT dated as of February 16, 2001 among DIMATECH CORPORATION, a
corporation organized under the laws of Japan (KK) ("Dimatech"); HIROYUKI
KATAOKA, the sole stockholder of Dimatech ("Seller"); and NETSILICON, INC., a
Massachusetts corporation ("NETsilicon").

                              W I T N E S S E T H :

      WHEREAS, NETsilicon desires to purchase from Seller all of the outstanding
shares of capital stock of Dimatech (the "Shares"); and

      WHEREAS, Seller desires to sell to NETsilicon all of such Shares;

      NOW, THEREFORE, the parties hereto agree as follows:

                                    ARTICLE I

                                   DEFINITIONS

         1.01. Definitions. The following terms, as used herein, have the
following meanings:

         "Affiliate" means, with respect to any Person, any Person directly or
indirectly controlling, controlled by, or under common control with such Person.

         "Balance Sheet Date" means January 31, 2001.

         "Closing Date" means the date of the Closing.

         "Common Stock" means the common stock or equivalent security of
Dimatech.

         "Dimatech's Proprietary Rights" means all Proprietary Rights which are
owned or licensed by Dimatech or any Affiliate of Dimatech and used or held for
use by Dimatech.

         "Employee" means any employee of Dimatech as of the date hereof.

         "Lien" means, with respect to any asset, any mortgage, lien, pledge,
charge, security interest, restriction or encumbrance of any kind in respect of
such asset.

         "Material Adverse Change" means a material adverse change in the
business, assets, condition (financial or otherwise), results of operations or
prospects (insofar as they relate to events or circumstances known only to
Dimatech and not generally known in the industry as of the Closing Date) of
Dimatech.

         "Material Adverse Effect" means a material adverse effect on the
business, assets, condition (financial or otherwise), results or operations or
prospects (insofar as they relate to
<PAGE>   6
events or circumstances known only to Dimatech and not generally known in the
industry as of the Closing Date) of Dimatech.

         "Person" means an individual, corporation, partnership, limited
liability company, association, trust or other entity or organization, including
a government or political subdivision or an agency or instrumentality thereof.

         "Proprietary Rights" means all (A) patents, patent applications, patent
disclosures and all related continuation, continuation-in-part, divisional,
reissue, re-examination, utility, model, certificate of invention and design
patents, patent applications, registrations and applications for registrations,
(B) trademarks, service marks, trade dress, logos, tradenames, service names and
corporate names and registrations and applications for registration thereof, (C)
copyrights and registrations and applications for registration thereof, (D) mask
works and registrations and applications for registration thereof, (E) trade
secrets and confidential business information, whether patentable or
nonpatentable and whether or not reduced to practice, know-how, manufacturing
and product processes and techniques, research and development information,
copyrightable works, financial, marketing and business data, pricing and cost
information, business and marketing plans and customer and supplier lists and
information, (F) other proprietary rights relating to any of the foregoing
(including without limitation associated goodwill and remedies against
infringements thereof and rights of protection of an interest therein under the
laws of all jurisdictions) and (G) copies and tangible embodiments thereof.

         "NETsilicon's Counsel" means the law firm of Testa, Hurwitz &
Thibeault, LLP, Boston, Massachusetts.

         "Seller's Counsel" means the law firm of Johnston & Associates,
Atlanta, Georgia.

         "Subsidiary" means any entity of which securities or other ownership
interests having ordinary voting power to elect a majority of the board of
directors or other persons performing similar functions are owned directly or
indirectly by Dimatech.

                                   ARTICLE II

                                PURCHASE AND SALE

      2.01. Purchase and Sale. Upon the terms and subject to the conditions of
this Agreement, Seller shall sell to NETsilicon, and NETsilicon shall purchase
from Seller, at the Closing, for the Purchase Price, all shares of Common Stock
or other equity interests in Dimatech, as scheduled in Schedule 2.01. The
aggregate purchase price for all Shares shall be equal to U.S. $250,000 in cash
and two hundred forty-one thousand six hundred and sixty-seven shares of
NETsilicon common stock. The Purchase Price shall be paid as provided in Section
2.02.


                                       2
<PAGE>   7
     2.02.  Closing.

         (a) Unless otherwise agreed in writing by the parties the closing of
the purchase and sale of the Shares hereunder (the "Closing") shall take place
by fax transmission of all necessary documents (with subsequent delivery of
executed original documents) simultaneously with the execution of this
Agreement.

         (b) At the Closing, NETsilicon shall deliver to Seller the Purchase
Price. Cash payable shall be paid by NETsilicon by wire transfer of immediately
available funds in accordance with written instructions to be provided to
NETsilicon by Seller to an account maintained by Seller's Counsel, and by
delivery of share certificates representing the requisite number of shares of
NETsilicon common stock registered in the name of Seller.

         (c) Seller shall deliver to NETsilicon share certificates for the
Shares duly endorsed for transfer to NETsilicon, with any required transfer
stamps affixed thereto.

         (d) The parties shall execute and deliver any other instruments,
documents and certificates that are required to be delivered pursuant to this
Agreement or as may be reasonably requested by any party in order to consummate
the transactions contemplated by this Agreement.

                                   ARTICLE III

                    REPRESENTATIONS AND WARRANTIES OF SELLER

         Seller hereby represents and warrants to NETsilicon as of the date
hereof that:

     3.01. Corporate Existence and Power. Dimatech is a corporation duly
incorporated, validly existing and in good standing under the laws of Japan, and
has all corporate powers and all material governmental licenses, authorizations,
consents and approvals required to carry on its business as now conducted.
Dimatech has heretofore delivered to NETsilicon true and complete copies of the
latest version of the Articles of Association ("Taikan") and any other
Regulations, including the Regulations concerning the Board of Directors of
Dimatech, all as currently in effect.

     3.02. Corporate Authorization. The execution, delivery and performance by
Dimatech of this Agreement and the consummation by Dimatech of the transactions
contemplated hereby are within Dimatech's corporate powers and have been duly
authorized by all necessary corporate action, including the Board approval of
the transfer of the Shares in this Agreement, on the part of Dimatech. This
Agreement constitutes valid and binding agreements of Dimatech and Seller.

     3.03. Governmental Authorization; Consents.

         (a) The execution, delivery and performance by Dimatech and Seller of
this Agreement require no action by or in respect of, or filing with, any
governmental body, agency, official or authority.


                                       3
<PAGE>   8
              (b) Except for any consents, approvals, waivers and other actions
as set forth in Schedule 3.03 ("Required Consents"), all of which have been
obtained, no consent, approval, waiver or other action by any Person under any
contract, agreement, indenture, lease, instrument or other document to which
Dimatech is a party or by which any of them is bound is required or necessary
for the execution, delivery and performance of this Agreement by Dimatech or the
consummation of the transactions contemplated hereby or thereby.

     3.04. Non-Contravention. Except as set forth in Schedule 3.12, the
execution, delivery and performance by Dimatech of this Agreement and the
consummation of the transactions contemplated hereby do not and will not (i)
contravene or conflict with the corporate charter or bylaws of Dimatech, (ii)
contravene or conflict with or constitute a violation of any provision of any
law, regulation, judgment, injunction, order or decree binding upon or
applicable to Dimatech; (iii) constitute a default under or give rise to any
right of termination, cancellation or acceleration of any right or obligation of
Dimatech or to a loss of any benefit to which Dimatech is entitled under any
provision of any agreement, contract or other instrument binding upon Dimatech
or any Permit or (iv) result in the creation or imposition of any Lien on any
asset of Dimatech.

     3.05. Capitalization. The authorized capital stock of Dimatech consists of
400 shares of Common Stock. As of the date hereof, there were outstanding 200
shares of Common Stock owned as set forth in Schedule 2.01. Except as set forth
in this Section, there are no outstanding (i) shares of capital stock, phantom
stock, stock appreciation rights or other securities or equity interests of
Dimatech, (ii) securities of Dimatech convertible into or exchangeable for
shares of capital stock or other securities or phantom or other equity interests
of Dimatech or (iii) options, warrants or other rights to acquire from Dimatech
any capital stock or other securities or phantom or other equity interests of
Dimatech (the items in clauses (i), (ii) and (iii) being referred to
collectively as the "Dimatech Securities"). There are no outstanding obligations
of Dimatech, actual or contingent, to issue or deliver or to repurchase, redeem
or otherwise acquire any Dimatech Securities. Without limiting the foregoing, it
is specifically represented that Dimatech has no liabilities or outstanding
payments or other obligations to Genicom in accordance with the agreement dated
November 21, 1995, or otherwise, and Dimatech has not assumed any liabilities or
obligations from Rastek Japan; and Genicom's option rights under the contract
with Rastek Japan expired on November 21, 2000 and therefore Genicom is not
entitled to exercise any option rights under said agreement.

     3.06. Subsidiaries. Dimatech does not have and never has had any
subsidiaries or any ownership or equity interest in or control of (direct or
indirect) any other person.

     3.07. Financial Statements. Dimatech has previously furnished NETsilicon
with true and complete copies of (i) the unaudited balance sheets of Dimatech as
of December 31, 1998,December 31, 1999 and October 31, 2000 and the unaudited
statements of operations, cash flows and changes in stockholders' equity of
Dimatech for the respective fiscal periods then ended,, and (ii) the unaudited
balance sheet of Dimatech as of January 31, 2001 (the "Unaudited Balance Sheet")
and the unaudited statements of income, cash flows and changes in stockholders'
equity of Dimatech for the three-month period ended January 31, 2001
(collectively, the "Financial Statements"). Each of the balance sheets included
in the Financial


                                       4
<PAGE>   9
Statements fairly presents in all material respects the financial position of
Dimatech as of its date, and the other statements included in the Financial
Statements fairly present in all material respects the results of operations,
cash flows and stockholders' equity, as the case may be, of Dimatech for the
periods therein set forth, in each case in accordance with generally accepted
accounting principles consistently applied during the periods involved except as
otherwise stated therein and, with respect to the unaudited interim financial
statements, for the omission of footnote disclosures and, to the extent
consistent with generally accepted accounting principles, normally recurring
non-material year-end audit adjustments.

         3.08. Absence of Certain Changes. Since the Balance Sheet Date, except
as reflected in the unaudited Financial Statements or in Schedule 3.08, Dimatech
has conducted its business in the ordinary course consistent with past practices
and there has not been:

         (a) any Material Adverse Change or any event, occurrence, development
or state of circumstances or facts which could reasonably be expected to result
in a Material Adverse Change;

         (b) any declaration, setting aside or payment of any dividend or other
distribution with respect to any Dimatech Securities or any repurchase,
redemption or other acquisition by Dimatech of any outstanding shares of capital
stock or other securities of, or other ownership interests in, Dimatech;

         (c) any incurrence, assumption or guarantee by Dimatech of any
indebtedness for borrowed money other than in the ordinary course of Dimatech's
business;

         (d) any creation or assumption by Dimatech of any material Lien on any
asset;

         (e) any making of any loan, advance or capital contributions to or
investment in any Person;

         (f) any damage, destruction or other casualty loss (whether or not
covered by insurance) affecting the business or assets of Dimatech which,
individually or in the aggregate, has had or would reasonably be expected to
have a Material Adverse Effect;

         (g) any transaction or commitment made, or any contract or agreement
entered into, by Dimatech relating to its assets or business (including the
acquisition or disposition of any assets) or any relinquishment by Dimatech of
any contract or other right, in either case, material to Dimatech, other than
transactions and commitments in the ordinary course of business consistent with
past practices and those contemplated by this Agreement;

         (h) any (i) grant of any severance or termination pay to any director,
officer or employee of Dimatech, except as expressly contemplated pursuant to
this Agreement, (ii) entering into of any employment, deferred compensation or
other similar agreement (or any material amendment to any such existing
agreement) with any director, officer or employee of Dimatech, except as
disclosed on Schedule 3.20, (iii) change in benefits payable under existing
severance or termination pay policies or employment agreements, except as
expressly


                                       5
<PAGE>   10
contemplated pursuant to this Agreement or (iv) change in compensation, bonus or
other benefits payable to directors, officers or employees of Dimatech; or

         (i) any labor dispute or any activity or proceeding by a labor union or
representation thereof to organize any employees of Dimatech, which employees
were not subject to a collective bargaining agreement at the Balance Sheet Date,
or any lockouts, strikes, slowdowns, work stoppages or threats thereof by or
with respect to any employees of Dimatech.

         3.09. Property and Equipment. (a) Dimatech has good and marketable
title to, or in the case of leased property has valid leasehold interests in,
all property and assets (whether tangible or intangible) reflected on the
Unaudited Balance Sheet or acquired after the Balance Sheet Date, except for
properties and assets sold since the Balance Sheet Date in the ordinary course
of business consistent with past practices. None of such properties or assets is
subject to any Liens, except:

                  (i) Liens disclosed on the Unaudited Balance Sheet;

                  (ii) Liens for taxes not yet due or being contested in good
         faith (and for which adequate accruals or reserves have been
         established on the Unaudited Balance Sheet); and

                  (iii) Liens which do not materially detract from the value of
         such property or assets as now used, or materially interfere with any
         present or intended use of such property or assets.

         (b) There are no developments affecting any of such properties or
assets pending or, to the knowledge of Dimatech threatened, which might
materially detract from the value of such property or assets, or have a Material
Adverse Effect on the marketability of such property or assets.

         (c) The equipment owned by Dimatech has no known material defects and
is substantially adequate for the uses to which it is being put.

         (d) The assets owned or leased by Dimatech, or which it otherwise has
the right to use, constitute all of the material assets held for use or used in
connection with the business of Dimatech and are generally adequate to conduct
such business as currently conducted.

         3.10. No Undisclosed Material Liabilities. There are no material
liabilities of Dimatech of any kind whatsoever, whether accrued, contingent,
absolute, determined, determinable or otherwise, and there is no existing
condition, situation or set of circumstances which could reasonably be expected
to result in such a liability, other than:

                  (i) liabilities disclosed or provided for in the Unaudited
         Balance Sheet; and


                                       6
<PAGE>   11
                  (ii) liabilities incurred in the ordinary course of business
         consistent with past practice since the Balance Sheet Date (none of
         which are for tort, breach of contract or violation of laws), which in
         the aggregate are not material to Dimatech.

         3.11. Litigation. There is no action, suit, investigation or proceeding
(or to Dimatech's knowledge any basis therefor) pending against, or to the
knowledge of Dimatech threatened against or affecting, Dimatech or any of its
respective properties or the transactions contemplated hereby before any court
or arbitrator or any governmental body, agency, official or authority.

         3.12. Material Contracts. (a) Except for agreements, contracts, plans,
leases, arrangements or commitments disclosed in Schedule 3.12 or any other
schedule to this Agreement, Dimatech is not a party to or subject to:

                  (i) any lease providing for annual rentals of $5,000 or more;

                  (ii) any contract for the purchase of materials, supplies,
         goods, services, equipment or other assets providing for annual
         payments by Dimatech of $5,000 or more;

                  (iii) any sales, distribution or other similar agreement
         providing for the sale by Dimatech of materials, supplies, goods,
         services, equipment or other assets providing for annual payments to
         Dimatech of $25,000 or more;

                  (iv) any partnership, joint venture or other similar contract,
         arrangement or agreement;

                  (v) any contract relating to indebtedness for borrowed money
         or the deferred purchase price of property (whether incurred, assumed,
         guaranteed or secured by any asset), except contracts relating to
         indebtedness incurred in the ordinary course of business in an amount
         not exceeding $25,000;

                  (vi) any license agreement, franchise agreement or agreement
         in respect of similar rights granted to or held by Dimatech;

                  (vii) any agency, dealer, sales representative or other
         similar agreement;

                  (viii) any contract or other document that limits the freedom
         of Dimatech to compete in any line of business or with any Person or in
         any area or which would so limit the freedom of Dimatech to conduct its
         business as presently conducted after the Closing Date; or

                  (ix) any other contract or commitment not made in the ordinary
         course of business that is material to Dimatech taken as a whole.


                                       7
<PAGE>   12
         (b) Each agreement, contract, plan, lease, arrangement and commitment
disclosed in any schedule to this Agreement or required to be disclosed pursuant
to Section 3.12(a) is a valid and binding agreement of Dimatech and is in full
force and effect, and neither Dimatech, nor, to the knowledge of Dimatech, any
other party thereto is in default in any material respect under the terms of any
such agreement, contract, plan, lease, arrangement or commitment.

         3.13. Insurance Coverage. Dimatech has furnished to NETsilicon a list
of, and true and complete copies of, all insurance policies and fidelity bonds
covering the assets, business, equipment, properties, operations, employees,
officers and directors of Dimatech. Dimatech does not know of any threatened
termination of, or premium increase (other than in the ordinary of business)
with respect to, any of such policies or bonds.

         3.14. Compliance with Laws; No Defaults.

         (a) Dimatech is not in violation of, or has not in the last three years
violated, any applicable provision of any laws, statutes, ordinances or
regulations, except for violations that have not had and would not reasonably be
expected to have, individually or in the aggregate, a Material Adverse Effect.

         (b) Schedule 3.14 correctly describes each license and permit material
to the business of Dimatech (a "Permit"), together with the name of the
governmental agency or entity issuing such Permit. Such Permits are valid and in
full force and effect, and none of such Permits will be terminated or impaired
or become terminable as a result of the transactions contemplated hereby.

         (c) Dimatech is not in default under, and no condition exists that with
notice or lapse of time or both would constitute a default under, (i) any
mortgage, loan agreement, indenture or evidence of indebtedness for borrowed
money to which Dimatech is a party or by which Dimatech or any material amount
of its assets is bound or (ii) any judgment, order or injunction of any court,
arbitrator or governmental body, agency, official or authority which defaults or
potential defaults individually or in the aggregate could reasonably be expected
to have a Material Adverse Effect.

         3.15. Finders' Fees. There is no investment banker, broker, finder or
other intermediary which has been retained by or is authorized to act on behalf
of Seller or Dimatech who might be entitled to any fee or commission from
NETsilicon, Dimatech or any of their respective Affiliates upon consummation of
the transactions contemplated by this Agreement.

         3.16. Intellectual Property.

         (a) Schedule 3.16 includes a list of all of Dimatech's Proprietary
Rights specifying as to each, as applicable: (i) the nature of such right; (ii)
the owner of such right; (iii) the jurisdictions, if any, by or in which such
right has been issued or registered or in which an application for such issuance
or registration has been filed, including the respective registration or
application numbers; if any; and (iv) licenses, sublicenses and other agreements
as to which Dimatech or any of its Affiliates is a party and pursuant to which
any Person is authorized to use


                                       8
<PAGE>   13
any such right, including the identity of all parties thereto, a description of
the nature and subject matter thereof, the applicable royalty and the term
thereof.

         (b) Dimatech has not during the three years preceding the date of this
Agreement been sued, charged in writing with or been a defendant in any claim,
suit, action or proceeding relating to its business that has not been finally
terminated prior to the date hereof and that involves a claim of infringement of
any patents, trademarks, service marks or copyrights, and (ii) Dimatech has no
knowledge of any other claim or infringement by Dimatech, and no knowledge of
any continuing infringement by any other Person of any of Dimatech's Proprietary
Rights. No Dimatech Proprietary Right is subject to any outstanding order,
judgment, decree, stipulation or agreement restricting the use thereof by
Dimatech or restricting the licensing thereof by Dimatech to any Person.
Dimatech has not entered into any agreement to indemnify any other Person
against any charge of infringement of any patent, trademark, service mark or
copyright.

         (c) To the best knowledge of Dimatech, all of Dimatech's trade secrets
and confidential information has been protected under all applicable laws.

         (d) To the knowledge of Dimatech, no third party has asserted any
claim, or has any reasonable basis to assert any valid claim, against Dimatech
with respect to (i) the continued employment by, or association with, Dimatech
of any of the present officers, employees of or consultants to Dimatech or (ii)
the use by Dimatech or any of such Persons in connection with their activities
for or on behalf of Dimatech of any information which Dimatech or any of such
Persons would be prohibited from using under any prior agreements or
arrangements or any laws applicable to unfair competition, trade secrets or
proprietary information.

         3.17. Inventories. The inventories set forth in the Unaudited Balance
Sheet were properly stated therein at the lesser of cost or fair market value
determined in accordance with generally accepted accounting principles
consistently applied by Dimatech. Since the Balance Sheet Date, the inventories
of Dimatech have been maintained in the ordinary course of business. All such
inventory is owned free and clear of all material Liens except as disclosed in
the Financial Statements. All of the inventory recorded on the Unaudited Balance
Sheet consists of, and all inventory on the Closing Date will consist of, items
of a quality usable or saleable in the ordinary course of business consistent
with past practices.

         3.18. Receivables. All accounts, notes receivable and other receivables
(other than receivables collected since the Balance Sheet Date) reflected on the
Unaudited Balance Sheet are, and all accounts and notes receivable of Dimatech
at the Closing Date will be, valid, genuine and the results of bona fide
transactions, subject to normal and customary trade discounts, less any reserves
for doubtful accounts recorded on the Unaudited Balance Sheet. All accounts,
notes receivable and other receivables of Dimatech at the Balance Sheet Date
have been included in the Unaudited Balance Sheet and as of the Closing, none of
such receivables shall have been outstanding for a period in excess of 120 days,
other than receivables that are the subject of a dispute (all of which have
previously been disclosed to NETsilicon), for which accruals have been made on
Dimatech's books.


                                       9
<PAGE>   14
         3.19. Taxes.

         (a) The term "Taxes" as used herein means all taxes and governmental
charges of any type, and the term "Tax" means any one of the foregoing Taxes.
The term "Tax Returns" as used herein means all returns, declarations, reports,
claims for refund, information statements and other documents relating to Taxes,
including all schedules and attachments thereto, and including all amendments
thereof, and the term "Tax Return" means any one of the foregoing Tax Returns.

         (b) Each of Dimatech and its subsidiaries has timely filed all Tax
Returns required to be filed and has paid all Taxes owed (whether or not shown
as due on such Tax Returns). All Tax Returns filed by Dimatech and its
subsidiaries were complete and correct in all respects, and such Tax Returns
correctly reflected the facts regarding the income, business, assets,
operations, activities, status and other matters of Dimatech and its
subsidiaries and any other information required to be shown thereon. Except as
set forth on Schedule 3.19, none of the Tax Returns filed by Dimatech and its
subsidiaries or Taxes payable by Dimatech or its subsidiaries have been the
subject of an audit, action, suit, proceeding, claim, examination, deficiency or
assessment by any governmental authority, and no such audit, action, suit,
proceeding, claim, examination, deficiency or assessment is currently pending
or, to the knowledge of Dimatech or any of its subsidiaries, threatened. Neither
Dimatech nor any of its subsidiaries is currently the beneficiary of any
extension of time within which to file any Tax Return, and neither Dimatech nor
any of its subsidiaries has waived any statute of limitation with respect to any
Tax or agreed to any extension of time with respect to a Tax assessment or
deficiency. All material elections with respect to Taxes affecting Dimatech or
any of its subsidiaries, as of the date hereof, are set forth in the Financial
Statements or in Schedule 3.19.

         (c) There are no liens for Taxes upon the assets of Dimatech. The
unpaid Taxes of Dimatech and its subsidiaries did not, as of the Balance Sheet
Date, exceed the reserve for actual Taxes (as opposed to any reserve for
deferred Taxes established to reflect timing differences between book and Tax
income) as shown on the Unaudited Balance Sheet, and will not exceed such
reserve as adjusted for the passage of time through the Closing Date in
accordance with the past custom and practice of Dimatech and its subsidiaries in
filing their Tax Returns (taking into account any Taxes incurred as a result of
the transactions contemplated by this Agreement).

         (d) Schedule 3.19 hereto contains a list of all jurisdictions (whether
foreign or domestic) to which any Tax is properly payable by either Dimatech or
any of its subsidiaries.

         3.20 Employees. Schedule 3.20 sets forth a list of (a) the titles,
salaries and all other compensation of all salaried Dimatech employees (such
term meaning permanent and temporary, full-time and part-time employees) and (b)
the wage rates for non-salaried Dimatech employees (by classification). Except
as expressly contemplated by this Agreement, no senior management or other key
employee has stated to Dimatech that such employee intends to resign or retire
as a result of the transactions contemplated by this Agreement or otherwise
within six months after the Closing Date. Dimatech has not, within the three
years immediately prior to the date of this Agreement been and, to the knowledge
of Dimatech, is not now subject to a union organizing


                                       10
<PAGE>   15
effort. Except as set forth on Schedule 3.20, Dimatech does not have any written
contract of employment or other employment, severance or similar agreement with
any of its employees or any established policy or practice relating thereto, and
all of its employees are employees-at-will. Dimatech is not a party to any
pending, or to Dimatech's knowledge, threatened, material labor dispute.

         3.21 Employee Benefit Plans. Each Plan covering active, former, or
retired employees of Dimatech in connection with their employment by Dimatech is
listed in Schedule 3.21 ("Plans"). "Plan" means any plan for the benefit of
employees, employment, severance or similar contract, arrangement or policy and
each plan or arrangement providing for benefits of any type, insurance coverage
(or for deferred compensation, profit-sharing, bonuses, phantom stock, stock
options, stock appreciation rights or other forms of incentive compensation or
post-retirement insurance, compensation or benefits, as well as any retirement
allowance, severance fees and pension plan or benefits. Dimatech has provided
NETsilicon with a copy of each written Plan, a summary of each oral Plan, and
where applicable, any related trust agreement, annuity, or insurance contract.
Each Plan has been maintained and administered in material compliance with its
terms and with the requirements prescribed by any and all statutes, orders,
rules and regulations which are applicable to such Plans. All contributions,
reserves, or payments to any Plan, which are due on or prior to the date hereof
with respect to any employee who participates therein solely on account of
employment with Dimatech have been made or provided for. There are no
restrictions on the rights of Dimatech to amend or terminate any Plan without
incurring any penalty thereunder. other than health care continuation benefits
required to be provided under applicable law.

         Except as contemplated by this Agreement, neither the execution and
delivery of this Agreement and all other agreements contemplated hereby, nor the
consummation of the transactions contemplated hereby will in the absence of any
other event or circumstance : (i) result in any payment by Dimatech (including,
without limitation, severance, unemployment compensation, parachute payment,
bonus or otherwise) becoming due to any director, employee, or independent
contractor of Dimatech under any Plan, agreement, or otherwise, (ii) increase
any benefits otherwise payable under any Plan or agreement.

         3.22 Customers and Suppliers. Dimatech has not received notice from or
is otherwise aware that any customer, or group of customers that is under common
ownership or control, and that accounted for more than 1% of the aggregate
products and services furnished by Dimatech during the past 12 months has
stopped or intends to stop purchasing Dimatech's products or services, nor has
Dimatech lost any supplier, or group of suppliers that is under common ownership
or control, that accounted for more than 1% of the aggregate supplies purchased
by Dimatech during the past 12 months nor has Dimatech received notice from or
is otherwise aware that any such supplier intends to stop supplying Dimatech.

         3.23 Products. To Dimatech's knowledge, each shipment or other delivery
of any products produced or sold by Dimatech made or to be made by Dimatech on
or prior to the Closing Date was or as of the Closing Date will be in compliance
in all material respects with all requirements of law and regulations
administered by any other governmental authority.


                                       11
<PAGE>   16
         3.24 Transactions with Affiliates. Except as set forth in Schedule
3.24, there are no loans, leases, royalty agreements or other continuing
transactions between Dimatech and Seller, any Affiliate of Seller, or any member
of Seller's family. To the knowledge of Dimatech, except as set forth in
Schedule 3.24, none of the officers or directors of Dimatech or Seller (a) has
any material direct or indirect interest in any entity which does business with
Dimatech; (b) has any direct or indirect interest in any property, asset or
right which is used by Dimatech in the conduct of its business; or (c) has any
contractual relationship with Dimatech other than such relationships which occur
from being an officer, director or stockholder of Dimatech.

         3.25 Other Information. None of this Agreement or any of the Exhibits
or Schedules hereto or thereto contains any untrue statement of a material fact
or omits to state a material fact necessary in order to make the statements
contained therein not misleading.

                                   ARTICLE IV

               ADDITIONAL REPRESENTATIONS AND WARRANTIES OF SELLER

         Seller represents and warrants to, and agrees with, NETsilicon as
follows:

         4.01. Title to and Validity of Shares. Seller now has, and on the
Closing Date will have, good and marketable title to and unrestricted power to
vote and sell the Shares designated as owned by Seller opposite Seller's name on
Schedule 2.01, free and clear of any Lien and, upon purchase and payment
therefor and delivery to NETsilicon thereof in accordance with the terms of this
Agreement, NETsilicon will obtain good and marketable title to such Shares free
and clear of any Lien, other than any Lien resulting from NETsilicon's ownership
of such Shares. All Shares owned by Seller have been duly authorized and validly
issued and are fully paid and non-assessable. All Shares to be sold by Seller
are registered in the name of Seller.

         4.02. Authority. Seller has the legal power, right and authority to
enter into and perform this Agreement, and to perform each of his obligations
hereunder. The execution, delivery and performance of this Agreement by Seller
(a) require no action by or in respect of, or filing with, or consent of, any
governmental body, agency or official or any other Person and (b) do not
contravene, or constitute a default under, any provision of applicable law or
regulation or of any agreement, judgment, injunction, order, decree or any other
instrument binding upon Seller. This Agreement has been duly executed and
delivered by Seller and constitutes a valid and binding obligation of Seller,
enforceable in accordance with its terms.

                                    ARTICLE V

                     REPRESENTATIONS AND WARRANTIES OF BUYER

         NETsilicon hereby represents and warrants to Dimatech and Sellers that:

         5.01. Organization and Existence. NETsilicon is a corporation duly
incorporated, validly existing and in good standing under the laws of
Massachusetts and has all corporate powers and all material governmental
licenses, authorizations, consents and approvals required to carry on its


                                       12
<PAGE>   17
business as now conducted. A true and complete copy of the latest version of
NETsilicon's corporate charter and bylaws is set forth in its filings with the
Securities and Exchange Commission.

         5.02. Corporate Authorization. The execution, delivery and performance
by NETsilicon of this Agreement and the consummation by NETsilicon of the
transactions contemplated hereby are within the corporate powers of NETsilicon
and have been duly authorized by all necessary corporate action on the part of
NETsilicon, including approval of the NETsilicon Board of Directors. This
Agreement constitutes the valid and binding agreement of NETsilicon. No consent,
approval, waiver or other action by any Person under any contract, agreement,
indenture, lease, instrument or other document to which NETsilicon is a party or
by which it is bound is required or necessary for the execution, delivery and
performance of this Agreement by NETsilicon or the consummation of the
transactions contemplated hereby or thereby.

         5.03. Governmental Authorization. The execution, delivery and
performance by NETsilicon of this Agreement require no action by or in respect
of, or filing with, any governmental body, agency, official or authority.

         5.04. Non-Contravention. The execution, delivery and performance by
NETsilicon of this Agreement does not and will not (i) contravene or conflict
with the corporate charter or bylaws of NETsilicon or (ii) contravene or
conflict with or constitute a violation of any provision of any law, regulation,
judgment, injunction, order or decree binding upon or applicable to NETsilicon;
(iii) constitute a default under or give rise to any right of termination,
cancellation or acceleration of any right or obligation of NETsilicon or to a
loss of any benefit to which NETsilicon is entitled under any provision of any
agreement, contract or other instrument binding upon NETsilicon or any Permit or
(iv) result in the creation or imposition of any Lien on any asset of
NETsilicon.

         5.05. Finders' Fees. There is no investment banker, broker, finder or
other intermediary which has been retained by or is authorized to act on behalf
of NETsilicon who might be entitled to any fee or commission from NETsilicon,
Dimatech or any of their respective Affiliates thereof upon consummation of the
transactions contemplated by this Agreement.

         5.06. Litigation. . Except as set forth in NETsilicon's filings with
the Securities and Exchange Commission, there is no action, suit, investigation
or proceeding (or to NETsilicon's knowledge any basis therefor) pending against,
or to the knowledge of NETsilicon threatened against or affecting, NETsilicon or
any of its respective properties or the transactions contemplated hereby before
any court or arbitrator or any governmental body, agency, official or authority.

         5.07. Compliance with Laws. NETsilicon is not in violation of, or has
not in the last three years violated, any applicable provision of any laws,
statutes, ordinances or regulations, except for violations that have not had and
would not reasonably be expected to have, individually or in the aggregate, a
Material Adverse Effect.


                                       13
<PAGE>   18
         5.08. Transactions with Affiliates. Except as set forth in NETsilicon's
filings with the Securities and Exchange Commission, there are no material
loans, leases, royalty agreements or other continuing transactions between
NETsilicon and any Affiliate of NETsilicon, any officer or director of
NETsilicon, or any family member of the officers and directors of NETsilicon. To
the knowledge of NETsilicon, except as set forth in NETsilicon's filings with
the Securities and Exchange Commission, none of the officers or directors of
NETsilicon: (a) has any material direct or indirect interest in any entity which
does business with NETsilicon; (b) has any direct or indirect interest in any
material property, asset or right which is used by NETsilicon in the conduct of
its business; or (c) has any material contractual relationship with NETsilicon
other than such relationships which occur from being an officer, director or
stockholder of NETsilicon.

                                   ARTICLE VI

                                    COVENANTS

         6.01. Resignations. Dimatech will deliver to NETsilicon the
resignations of all officers and directors of Dimatech from their positions with
Dimatech at or prior to the Closing Date, unless otherwise agreed by the
parties. It is contemplated that the representative director of Dimatech shall
remain in office pending his replacement by a nominee of NETsilicon, if
NETsilicon should choose to elect such a nominee.

         6.02. Further Assurances. Seller and NETsilicon each agree and
NETsilicon agrees to cause Dimatech after the Closing, to execute and deliver
such other documents, certificates, agreements and other writings and to take
such other actions as may be necessary or desirable in order to consummate or
implement expeditiously the transactions contemplated by this Agreement.

         6.03. Public Announcements. The parties agree to consult with each
other before issuing any press release or making any public statement or other
announcement with respect to this Agreement or the transactions contemplated
hereby (including with respect to the timing and manner of any such
announcement) and, except as may be required by applicable law or any listing
agreement with any national securities exchange, will not issue any such press
release or make any such public statement prior to such consultation.

                                   ARTICLE VII

                              CONDITIONS TO CLOSING

         7.01. Conditions to the Obligations of Each Party. The obligations of
NETsilicon, Dimatech and Seller to consummate the Closing are subject to the
satisfaction of the following conditions:

         (a) No proceeding challenging this Agreement or the transactions
contemplated hereby or seeking to prohibit, alter, prevent or materially delay
the Closing shall have been instituted by any Person before any court,
arbitrator or governmental body, agency or official and be pending.


                                       14
<PAGE>   19
         (b) Any Required Consents on Schedule 3.03 shall have been obtained,
and all other actions by or in respect of or filings with any governmental body,
agency, official or authority required to permit the consummation of the Closing
shall have been obtained.

         7.02. Conditions to Obligations of NETsilicon. The obligation of
NETsilicon to consummate the Closing is subject to the satisfaction of the
following further conditions:

         (a)(i) Dimatech and Seller shall have performed in all material
respects all of its or his obligations hereunder required to be performed on or
prior to the Closing Date, (ii) the representations and warranties of Dimatech
and Seller contained in this Agreement, disregarding all qualifications and
exceptions contained therein relating to "materiality" or "Material Adverse
Effect", shall be true in all material respects at and as of the Closing Date,
as if made at and as of such date and (iii) NETsilicon shall have received a
certificate signed by Seller (with respect to his obligations and
representations and warranties) to the foregoing effect.

         (b) No court, arbitrator or governmental body, agency or official shall
have issued any order, and there shall not be any statute, rule or regulation,
restraining the effective operation by NETsilicon of the business of Dimatech
after the Closing Date, and no proceeding challenging this Agreement or the
transactions contemplated hereby or seeking to prohibit, alter, prevent or
materially delay the Closing shall have been instituted by any Person before any
court, arbitrator or governmental body, agency or official and be pending.

         (c) Prior to the Closing Date, Seller shall provide NETsilicon with all
tax clearance certificates or similar documents which may be required by any
governmental authority in order to relieve NETsilicon of any obligation to
withhold any portion of the Purchase Price (or determined to be necessary by
NETsilicon in its sole discretion).

         (d) Seller shall deliver to NETsilicon share certificates for the
Shares duly endorsed for transfer to NETsilicon, with any required transfer
stamps affixed thereto.

         (e) Seller shall deliver to NETsilicon a copy of the minutes of the
Board of Directors wherein the transfer of the Shares contemplated hereby has
been approved, certified by the representative Director of Dimatech.

         7.03. Conditions to Obligations of Seller. The obligation of Seller to
consummate the Closing is subject to the satisfaction of the following further
conditions:

         (a)(i) NETsilicon shall have performed in all material respects all of
its obligations hereunder required to be performed by it at or prior to the
Closing Date, (ii) the representations and warranties of NETsilicon contained in
this Agreement, disregarding the qualifications and exceptions contained therein
relating to "materially" or "Material Adverse Effect", shall be true in all
material respects at and as of the Closing Date, as if made at and as of such
date and (iii) Seller shall have received a certificate signed by the President
of NETsilicon to the foregoing effect.


                                       15
<PAGE>   20
         (b) No proceeding challenging this Agreement or the transactions
contemplated hereby or seeking to prohibit, alter, prevent or materially delay
the Closing shall have been instituted by any Person before any court,
arbitrator or governmental body, agency or official and be pending.

         (c) Seller shall have received all items specified in Section 2.02 of
this Agreement and all other closing documents that they may reasonably request,
all in form and substance reasonably satisfactory to them.

         (d) Seller shall have received a registration rights agreement and an
employment agreement executed by NETsilicon in the forms previously furnished to
him.

         (e) NETsilicon shall deliver to Seller a copy of the minutes of the
Board of Directors approving the transactions contemplated by this Agreement.,
certified by the Secretary or Assistant Secretary of NETsilicon.

                                  ARTICLE VIII

                                 INDEMNIFICATION

         8.01. Indemnification Relating to Agreement. Subject to Sections 8.04
and 8.05, Seller hereby agrees to defend, indemnify and hold NETsilicon harmless
from and against, and to reimburse NETsilicon with respect to, any and all
losses, damages, liabilities, claims, judgments, settlements, fines, costs and
expenses (including reasonable attorneys' fees), determined as provided in
Section 8.04 ("Indemnifiable Amounts") of every nature whatsoever incurred by
NETsilicon (which will be deemed to include any of the foregoing incurred by
Dimatech) by reason of or arising out of or in connection with (i) any breach,
or any claim (including claims by parties other than NETsilicon) that
constitutes a breach, by Dimatech or any of Seller of any representation or
warranty of Dimatech or Seller contained in this Agreement or in any certificate
or other document delivered to NETsilicon pursuant to this Agreement, (ii) the
failure, partial or total, of Dimatech or any Seller to perform any agreement or
covenant required by this Agreement to be performed by it or them and (iii) any
Tax liability, or asserted liability, of Dimatech, but only to the extent such
liabilities were not accrued for on, or disclosed in any notes to, the Unaudited
Balance Sheet. The foregoing obligations to indemnify NETsilicon will be
determined without regard to any right to indemnification or reimbursement to
which any Person may have in his or her capacity as an officer, director,
employee, agent or any other capacity of Dimatech, and no Seller will be
entitled to any indemnification or reimbursement from Dimatech or NETsilicon for
amounts paid hereunder. There will be no right of contribution or subrogation
from NETsilicon or Dimatech for indemnification payments made by or for the
account of any Seller.

         8.02. Third Party Claims. With respect to any claims or demands by
third parties as to which NETsilicon may seek indemnification hereunder,
whenever NETsilicon will have received a written notice that such a claim or
demand has been asserted or threatened, NETsilicon will promptly notify the
Seller of such claim or demand and of the facts within NETsilicon's


                                       16
<PAGE>   21
knowledge that relate thereto within a reasonable time after receiving such
written notice. Seller will then have the right to defend, contest, negotiate or
settle any such claim or demand through counsel of their or his own selection,
reasonably satisfactory to NETsilicon, and solely at Seller's own cost and
expense. Notwithstanding the preceding sentence, Seller will not settle,
compromise, or offer to settle or compromise any such claim or demand without
the prior written consent of NETsilicon, which consent will not be unreasonably
withheld. Without limiting NETsilicon's rights to object for other reasons,
NETsilicon may object to a settlement or compromise which includes any provision
which in its reasonable judgment may have an adverse impact on or establish an
adverse precedent for NETsilicon or any of its subsidiaries. If Seller gives
notice to NETsilicon within twenty (20) calendar days after NETsilicon has
notified Seller that any such claim or demand has been made in writing, that the
Seller elect to have NETsilicon defend, contest, negotiate, or settle any such
claim or demand, then NETsilicon will have the right to contest and/or settle
any such claim or demand and seek indemnification pursuant to this Article VIII
as to any Indemnifiable Amounts; provided, however, that NETsilicon will not
settle, compromise, or offer to settle or compromise any such claim or demand
without the prior written consent (which may include a general or limited
consent) of the Seller, which consent will not be unreasonably withheld. If the
Seller fails to give written notice to NETsilicon of Seller's intention to
contest or settle any such claim or demand within twenty (20) calendar days
after NETsilicon has notified Seller that any such claim or demand has been made
in writing, or if any such notice is given but any such claim or demand is not
contested by Seller within a reasonable time thereafter, NETsilicon will have
the right to contest and/or settle any such claim or demand in its sole
discretion and seek indemnification pursuant to this Article XI as to any
Indemnifiable Amounts.

         8.03. Tax Contests. NETsilicon shall have the right to conduct any Tax
audit or other Tax contest relating to Dimatech. NETsilicon will conduct any
such Tax audit or other Tax contest in good faith.

         8.04. Limitations. Notwithstanding any other provision in this Article
VIII, NETsilicon will be entitled to indemnification only to the extent that the
aggregate Indemnifiable Amounts (which shall be determined for all purposes of
this Article VIII disregarding any qualification in any representation or
warranty as to "materially" or "material") exceed $25,000 (the "Threshold
Amount").

         8.05. Time Limit. The representations, warranties, covenants and
agreements of Dimatech and the Seller set forth in this Agreement will survive
the Closing and the consummation of the transactions contemplated by this
Agreement, but any claims with respect thereto may be made only on or before the
twelve (12) month anniversary of the date of this Agreement; provided, however,
that claims relating to Tax matters may be made only on or before the expiration
of the applicable Tax statute of limitations (including extensions thereof).

         8.06. Post-Closing Dimatech Operations. Without limiting the foregoing
provisions of this Article VIII, NetSilicon hereby agrees to defend, indemnify
and hold Seller harmless from and against, to reimburse Seller with respect to,
and to assume the defense of, any and all losses, damages, liabilities, claims,
judgments, settlements, fines, costs and expenses (including reasonable
attorneys' fees) of every nature whatsoever incurred by Seller arising out of
the post-


                                       17
<PAGE>   22
closing operations of Dimatech to the fullest extent permitted by the
Massachusetts Business Corporation Law and the Articles of Organization and
By-laws of NetSilicon.


                                   ARTICLE IX

                                  MISCELLANEOUS

         9.01. Notices. All notices, requests and other communications to either
party hereunder shall be in writing (including fax or similar writing) and shall
be given,

              if to NETsilicon, to:

                     NetSilicon, Inc.
                     411 Waverly Oaks Road
                     Building 227
                     Waltham, MA  02452
                     Attention: Chief Financial Officer
                     Fax: (781) 398-4877

                     with a copy to:

                     Edwin L. Miller, Jr., Esq.
                     Testa, Hurwitz & Thibeault, LLP
                     125 High Street
                     Boston, MA 02110
                     Fax: (617) 248-7100


              if to Dimatech, c/o Netsilicon


              if to Seller:

                          Hiroyuki Kataoka c/o Carl R. Johnston, Esq.
                           Johnston & Associates
                              2900 Chamblee Tucker Road, Bldg. 5
                             Atlanta, GA 30341

         9.02. Amendments; No Waivers. (a) Any provision of this Agreement may
be amended or waived prior to the Closing Date if, and only if, such amendment
or waiver is in writing and signed by NETsilicon, Dimatech and Seller.

         (b) No failure or delay by either party in exercising any right, power
or privilege hereunder shall operate as a waiver thereof nor shall any single or
partial exercise thereof preclude any other or further exercise thereof or the
exercise of any other right, power or


                                       18
<PAGE>   23
privilege. The rights and remedies herein provided shall be cumulative and not
exclusive of any rights or remedies provided by law.

         9.03. Expenses. Except as otherwise set forth in this Agreement, all
costs and expenses incurred in connection with this Agreement shall be paid by
the party incurring such cost or expense, except that all costs and expenses of
Dimatech in connection with this Agreement shall be paid by Seller, other than
payments for legal and accounting expenses made by Dimatech prior to the Closing
Date and which are reflected in or accrued for in the January 31, 2001 balance
sheet of Dimatech. Notwithstanding the foregoing, NETsilicon agrees to bear the
costs of any financial audits requested by it in connection with the
transactions contemplated by this Agreement.

         9.04. Successors and Assigns. The provisions of this Agreement shall be
binding upon and inure to the benefit of the parties hereto and their respective
successors and assigns; provided that no party may assign, delegate or otherwise
transfer any of his or its rights or obligations under this Agreement without
the consent of the other parties hereto, except that NETsilicon may transfer or
assign, in whole or from time to time in part, to one or more of its Affiliates,
the right to purchase all or a portion of the Shares, but no such transfer or
assignment will relieve NETsilicon of its obligations hereunder.

         9.05. Further Assurances. From time to time after the Closing, at the
request of NETsilicon, Dimatech or Seller and without further consideration,
NETsilicon or Dimatech, on the other hand, and Seller, on the other hand, will
execute and deliver to the other such other documents, and take such other
action, as such requesting party may reasonably request in order to consummate
more effectively the transactions contemplated hereby and to vest in NETsilicon
good, valid and marketable title to the Shares.

         9.06. Governing Law. This Agreement shall be construed in accordance
with and governed by the internal laws, and not the conflicts of law principles,
of the Commonwealth of Massachusetts, United States of America.

         9.07. Counterparts; Effectiveness. This Agreement may be signed in any
number of counterparts, each of which shall be an original, with the same effect
as if the signatures thereto and hereto were upon the same instrument. This
Agreement shall become effective when each party hereto shall have executed a
counterpart hereof.

         9.08. Entire Agreement. This Agreement and the documents executed at
the Closing constitute the entire agreement between the parties with respect to
the subject matter hereof and supersede all prior agreements, understandings and
negotiations, both written and oral, between the parties with respect to the
subject matter hereof. No representation, inducement, promise, understanding,
condition or warranty not set forth herein has been made or relied upon by any
party hereto. Neither this Agreement nor any provision hereof or thereof is
intended to confer upon any Person other than the parties hereto any rights or
remedies hereunder.

         9.09 Knowledge. For purposes of this Agreement, the term "knowledge"
(including any derivation thereof such as "know" or "knowing" and regardless of
whether such word starts with


                                       19
<PAGE>   24
an initial capital) in reference to Dimatech will mean the knowledge of the
directors and executive officers of Dimatech and Seller.

         9.10. Captions. The captions herein are included for convenience of
reference only and shall be ignored in the construction or interpretation
hereof.

         9.11 Severability. Any term or provision of this Agreement that is
invalid or unenforceable in any situation in any jurisdiction shall not affect
the validity or enforceability of the remaining terms and provisions hereof or
the validity or enforceability of the offending term or provision in any other
situation or in any other jurisdiction.

                  [REMAINDER OF PAGE INTENTIONALLY LEFT BLANK.]



                                       20
<PAGE>   25
              IN WITNESS WHEREOF, the parties hereto have duly executed this
Agreement as of the day and year first above written.

                                          NETSILICON, INC.


                                          By: /s/ Daniel Sullivan
                                             ------------------------------
                                             Title: CFO


                                          DIMATECH CORPORATION


                                          By: /s/ Takehiko Kataoka
                                             ------------------------------
                                             Takehiko Kataoka
                                              Representative Director


                                          /s/ Hiroyuki Kataoka
                                          ---------------------------------
                                          Hiroyuki Kataoka



                                       21