content: <PAGE>   1
  
  
       As filed with the Securities and Exchange Commission on August 30, 2000
  
                                                      Registration No. 333-_______
  
  ================================================================================
  
                         SECURITIES AND EXCHANGE COMMISSION
                               WASHINGTON, D.C. 20549
  
                                  -----------------
  
                                      FORM S-8
  
                            REGISTRATION STATEMENT UNDER
                             THE SECURITIES ACT OF 1933
  
                                  NETsilicon, Inc.
               (Exact Name of Registrant as specified in its charter)
  
            Massachusetts                                          04-2826579
  (State or other jurisdiction of                               (I.R.S. Employer
   incorporation or organization)                              Identification No.)
  
                                  -----------------
  
                          411 WAVERLEY OAKS ROAD, BLDG. 227
                                  WALTHAM, MA 02452
                                   (781) 647-1234
                 (Address of Principal Executive Offices) (Zip Code)
  
                                  -----------------
  
                                  NETSILICON, INC.
                          2000 EMPLOYEE STOCK PURCHASE PLAN
                              (Full title of the plan)
  
                                  -----------------
  
                               CORNELIUS PETERSON VIII
                        PRESIDENT AND CHIEF EXECUTIVE OFFICER
                                  NETSILICON, INC.
                          411 WAVERLEY OAKS ROAD, BLDG. 227
                                  WALTHAM, MA 02452
                 (Name and Address of Agent for Service of Process)
  
                                   (781) 647-1234
            (Telephone Number, Including Area Code, of Agent For Service)
  
  
                                  -----------------
  
                                      Copy to:
  
                             EDWIN L. MILLER, JR., ESQ.
                           TESTA, HURWITZ & THIBEAULT, LLP
                                   125 HIGH STREET
                             BOSTON, MASSACHUSETTS 02110
                                   (617) 248-7000
  
  ================================================================================
  
  
  <PAGE>   2
  
  
                           CALCULATION OF REGISTRATION FEE
  
  <TABLE>
  <CAPTION>
  
  ===================================================================================================================
                                                                    Proposed
                                                                    Maximum        Proposed
                                                                    Offering       Maximum
  Title of Securities                            Amount to be      Price Per       Aggregate        Amount of
  to be Registered                                Registered         Share      Offering Price    Registration Fee(2)
  
  <C>                                              <C>              <C>          <C>              <C>
  2000 Employee Stock Purchase Plan
  Common Stock (par value $.01 per share)           500,000          $25.38(1)     $12,690,000        $3,350.16
  
  ===================================================================================================================
  </TABLE>
  
  (1) These shares are not subject to outstanding options. The price of $25.38 per
      share, which is the average of the high and low prices reported on the
      Nasdaq National Market on August 29, 2000, is set forth solely for purposes
      of calculating the filing fee pursuant to Rule 457(c) and (h) and has been
      used for shares without a fixed exercise or purchase price.
  
  (2) Calculated pursuant to Section 6(b) of the Securities Act of 1933, as
      amended.
  
  
  
                                         2
  
  <PAGE>   3
  
                                       PART I
  
                INFORMATION REQUIRED IN THE SECTION 10(a) PROSPECTUS
  
  Item 1.  PLAN INFORMATION.
           -----------------
  
           The documents containing the information specified in this Item 1 will
  be sent or given to employees as specified by Rule 428(b)(1). In accordance with
  the rules and regulations of the Securities and Exchange Commission (the
  "Commission") and the instructions to Form S-8, such documents are not being
  filed with the Commission either as part of this Registration Statement or as
  prospectuses or prospectus supplements pursuant to Rule 424.
  
  Item 2.  REGISTRANT INFORMATION AND EMPLOYEE PLAN ANNUAL INFORMATION.
           ------------------------------------------------------------
  
           The documents containing the information specified in this Item 2 will
  be sent or given to employees as specified by Rule 428(b). In accordance with
  the rules and regulations of the Commission and the instructions to Form S-8,
  such documents are not being filed with the Commission either as part of this
  Registration Statement or as prospectuses or prospectus supplements pursuant to
  Rule 424.
  
  
  
                                       PART II
  
                 INFORMATION REQUIRED IN THE REGISTRATION STATEMENT
  
  
  Item 3.  INCORPORATION OF DOCUMENTS BY REFERENCE.
           ----------------------------------------
  
           The following documents filed with the Commission are incorporated by
  reference in this Registration Statement:
  
  (a)      Registrant's Annual Report on Form 10-K for the year ended January 31,
           2000, as filed with the Commission pursuant to Section 13(a) or 15(d)
           of the Securities Exchange Act of 1934, as amended (the "Exchange
           Act");
  
  (b)      All other reports filed pursuant to Section 13(a) or 15(d) of the
           Exchange Act since the end of the fiscal year covered by the
           Registrant's document referred to in (a) above.
  
  (c)      The section entitled "Description of Registrant's Securities to be
           Registered" contained in the Registrant's Registration Statement on
           Form 8-A (File No. 000-26761) filed on July 20, 1999 pursuant to
           Section 12(g) of the Exchange Act.
  
           All documents subsequently filed with the Commission by the Registrant
  pursuant to Sections 13(a), 13(c), 14 and 15(d) of the Exchange Act, prior to
  the filing of a post-effective amendment which indicates that all securities
  offered herein have been sold or which deregisters all securities then remaining
  unsold, shall be deemed to be incorporated by reference in this Registration
  Statement and to be a part thereof from the date of filing of such documents.
  
  
                                         3
  
  <PAGE>   4
  
  Item 4.  DESCRIPTION OF SECURITIES.
           --------------------------
  
           Not applicable.
  
  Item 5.  INTERESTS OF NAMED EXPERTS AND COUNSEL.
           ---------------------------------------
  
           Not applicable.
  
  Item 6.  INDEMNIFICATION OF DIRECTORS AND OFFICERS.
           ------------------------------------------
  
           The Restated Articles of Organization and the Amended and Restated
  By-Laws of the Company provide for indemnification of the Company's directors
  and officers unless such indemnification is prohibited by the Massachusetts
  Business Corporation Law. The Massachusetts Business Corporation Law generally
  permits indemnification of the Company's directors and officers for liabilities
  and expenses that they may incur in such capacities, except with respect to any
  matter that the indemnified person shall have been adjudicated in any proceeding
  not to have acted in good faith in the reasonable belief that his or her action
  was in the best interest of the Company. Reference is made to the Registrant's
  Restated Articles of Organization filed as Exhibit 3.1 to the Registrant's
  Registration Statement on Form S-1 (File No. 333-62231) and the Registrant's
  Amended and Restated By-Laws filed as Exhibit 3.3 to the Registrant's
  Registration Statement on Form S-1 (File No. 333-62231).
  
           The underwriting agreement, dated September 15, 1999, by and between
  the Registrant and the underwriters listed therein provides that the
  underwriters are obligated, under certain circumstances, to indemnify directors,
  officers and controlling persons of the Registrant against certain liabilities,
  including liabilities under the Securities Act. Reference is made to the Form of
  Underwriting Agreement filed as Exhibit 1.1 to the Registrant's Registration
  Statement on Form S-1 (File No. 333-62231).
  
           The Registrant has in effect a directors' and officers' insurance
  policy.
  
  Item 7.  EXEMPTION FROM REGISTRATION CLAIMED.
           ------------------------------------
  
           Not applicable.
  
  Item 8.  EXHIBITS.
           ---------
  
  
  EXHIBIT NO.                       DESCRIPTION OF EXHIBIT
  -----------                       ----------------------
  
    4.1       Specimen Certificate for shares of the Registrant's Common Stock
              (filed as Exhibit 4 to the Registrant's Registration Statement on
              Form S-1 (File No. 333-62231) and incorporated herein by reference)
  
    4.2       Restated Articles of Organization (filed as Exhibit 3.1 to the
              Registrant's Registration Statement on Form S-1 (File No. 333-62231)
              and incorporated herein by reference)
  
    4.3       Amended and Restated By-Laws of the Registrant (filed as Exhibit 3.3
              to the Registration Statement on Form S-1 (File No. 333-62231) and
              incorporated herein by reference)
  
                                         4
  <PAGE>   5
  
  
    4.4       NETsilicon, Inc. 2000 Employee Stock Purchase Plan
  
    5.1       Opinion of Testa, Hurwitz & Thibeault, LLP
  
   23.1       Consent of Testa, Hurwitz & Thibeault, LLP (included in Exhibit 5.1)
  
   23.2       Consent of BDO Seidman, LLP
  
   24.1       Power of Attorney (included as part of the signature page of this
              Registration Statement)
  
  Item 9.  UNDERTAKINGS.
           -------------
  
           (a)   The undersigned Registrant hereby undertakes:
  
                 (1)  To file, during any period in which offers or sales are
                 being made, a post-effective amendment to this registration
                 statement:
  
                      (i) To include any prospectus required by Section 10(a)(3)
                      of the Securities Act of 1933;
  
                      (ii) To reflect in the prospectus any facts or events
                      arising after the effective date of the registration
                      statement (or the most recent post-effective amendment
                      thereof) which, individually or in the aggregate, represent
                      a fundamental change in the information set forth in the
                      registration statement. Notwithstanding the foregoing, any
                      increase or decrease in volume of securities offered (if the
                      total dollar value of securities offered would not exceed
                      that which was registered) and any deviation from the low or
                      high end of the estimated maximum offering range may be
                      reflected in the form of prospectus filed with the
                      Commission pursuant to Rule 424(b) if, in the aggregate, the
                      changes in volume and price represent no more than a 20
                      percent change in the maximum aggregate offering price set
                      forth in the "Calculation of Registration Fee" table in the
                      effective registration statement;
  
                      (iii) To include any material information with respect to
                      the plan of distribution not previously disclosed in the
                      registration statement or any material change to such
                      information in the registration statement;
  
                      PROVIDED, HOWEVER, that paragraphs (a)(1)(i) and (a)(1)(ii)
                      do not apply if the registration statement is on Form S-3,
                      Form S-8 or Form F-3, and the information required to be
                      included in a post-effective amendment by those paragraphs
                      is contained in periodic reports filed with or furnished to
                      the Commission by the Registrant pursuant to Section 13 or
                      Section 15(d) of the Securities Exchange Act of 1934 that
                      are incorporated by reference in the Registration Statement.
  
                                         5
  
  <PAGE>   6
  
                 (2) That, for the purpose of determining any liability under the
                 Securities Act of 1933, each such post-effective amendment shall
                 be deemed to be a new registration statement relating to the
                 securities offered therein, and the offering of such securities
                 at that time shall be deemed to be the initial bona fide offering
                 thereof;
  
                 (3) To remove from registration by means of a post-effective
                 amendment any of the securities being registered which remain
                 unsold at the termination of the offering.
  
           (b)  The undersigned Registrant hereby undertakes that, for purposes of
           determining any liability under the Securities Act of 1933, each filing
           of the Registrant's annual report pursuant to Section 13(a) or Section
           15(d) of the Securities Exchange Act of 1934 (and, where applicable,
           each filing of an employee benefit plan's annual report pursuant to
           Section 15(d) of the Securities Exchange Act of 1934) that is
           incorporated by reference in the registration statement shall be deemed
           to be a new registration statement relating to the securities offered
           therein, and the offering of such securities at that time shall be
           deemed to be the initial bona fide offering thereof.
  
           (c)  Insofar as indemnification for liabilities arising under the
           Securities Act of 1933 may be permitted to directors, officers and
           controlling persons of the Registrant pursuant to the foregoing
           provisions, or otherwise, the Registrant has been advised that in the
           opinion of the Securities and Exchange Commission such indemnification
           is against public policy as expressed in the Act and is, therefore,
           unenforceable. In the event that a claim for indemnification against
           such liabilities (other than the payment by the Registrant of expenses
           incurred or paid by a director, officer or controlling person of the
           Registrant in the successful defense of any action, suit or proceeding)
           is asserted by such director, officer or controlling person in
           connection with the securities being registered, the Registrant will,
           unless in the opinion of its counsel the matter has been settled by
           controlling precedent, submit to a court of appropriate jurisdiction
           the question whether such indemnification by it is against public
           policy as expressed in the Act and will be governed by the final
           adjudication of such issue.
  
                                         6
  
  <PAGE>   7
  
                                     SIGNATURES
  
           Pursuant to the requirements of the Securities Act of 1933, the
  Registrant certifies that it has reasonable grounds to believe that it meets all
  of the requirements for filing on Form S-8 and has duly caused this Registration
  Statement to be signed on its behalf by the undersigned, thereunto duly
  authorized, in the City of Waltham in the State of Massachusetts, on this 30th
  day of August, 2000.
  
                                         NETsilicon, Inc.
  
  
                                         By: /s/ Cornelius Peterson, VIII
                                            --------------------------------
                                            Cornelius Peterson, VIII
                                            President and Chief Executive Officer
  
                          POWER OF ATTORNEY AND SIGNATURES
  
           We, the undersigned officers and directors of NETsilicon, Inc., hereby
  severally constitute and appoint Cornelius Peterson VIII and Daniel J. Sullivan,
  and each of them singly, our true and lawful attorneys, with full power to them
  and each of them singly, to sign for us in our names in the capacities indicated
  below, any amendments to this Registration Statement on Form S-8 (including
  post-effective amendments), and to file the same, with all exhibits thereto and
  other documents in connection therewith, with the Securities and Exchange
  Commission, and generally to do all things in our names and on our behalf in our
  capacities as officers and directors to enable NETsilicon, Inc., to comply with
  the provisions of the Securities Act of 1933, as amended, hereby ratifying and
  confirming our signatures as they may be signed by our said attorneys, or any of
  them, to said Registration Statement and all amendments thereto.
  
           Pursuant to the requirements of the Securities Act of 1933, this
  Registration Statement has been signed by the following persons in the
  capacities and on the date indicated.
  
  <TABLE>
  <CAPTION>
  
               SIGNATURE                               TITLE                                     DATE
  
  <S>                                     <C>                                               <C>
  /s/ Cornelius Peterson, VIII            President, Chief Executive Officer and            August 30, 2000
  -------------------------------------   Director (Principal Executive Officer)
  Cornelius Peterson, VIII
  
  /s/ Daniel J. Sullivan                  Chief Financial Officer                           August 30, 2000
  -------------------------------------   (Principal Financial and Accounting Officer)
  Daniel J. Sullivan
  
  /s/ Michael K. Ballard                  Director                                          August 30, 2000
  -------------------------------------
  Michael K. Ballard
  
  /s/ Francis E. Girard                   Director                                          August 30, 2000
  -------------------------------------
  Francis E. Girard
  
  /s/ William Johnson                     Director                                          August 30, 2000
  -------------------------------------
  William Johnson
  
  /s/ Edward B. Roberts                   Director                                          August 30, 2000
  -------------------------------------
  Edward B. Roberts
  
  /s/ F. Grant Saviers                    Director                                          August 30, 2000
  -------------------------------------
  F. Grant Saviers
  </TABLE>
  
                                         7
  
  <PAGE>   8
  
                                  INDEX TO EXHIBITS
  
  EXHIBIT NO.    DESCRIPTION OF EXHIBIT
  -----------    ----------------------
  
    4.1          Specimen Certificate for shares of the Registrant's Common Stock
                 (filed as Exhibit 4 to the Registrant's Registration Statement on
                 Form S-1 (File No. 333-62231) and incorporated herein by
                 reference)
  
    4.2          Restated Articles of Organization (filed as Exhibit 3.1 to the
                 Registrant's Registration Statement on Form S-1 (File No.
                 333-62231) and incorporated herein by reference)
  
    4.3          Amended and Restated By-Laws of the Registrant (filed as Exhibit
                 3.3 to the Registration Statement on Form S-1 (File No.
                 333-62231) and incorporated herein by reference)
  
    4.4          NETsilicon, Inc. 2000 Employee Stock Purchase Plan
  
    5.1          Opinion of Testa, Hurwitz & Thibeault, LLP
  
   23.1          Consent of Testa, Hurwitz & Thibeault, LLP (included in
                 Exhibit 5.1)
  
   23.2          Consent of BDO Seidman, LLP
  
   24.1          Power of Attorney (included as part of the signature page of
                 this Registration Statement)
  
                                         8
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metadata_filer: {"company-data": {"conformed-name": "NETSILICON INC", "cik": "0001068885", "assigned-sic": "3577", "irs-number": "042826579", "state-of-incorporation": "MA", "fiscal-year-end": "0131"}, "filing-values": {"form-type": "S-8", "act": "33", "file-number": "333-44818", "film-number": "713822"}, "business-address": {"street1": "411 WAVERLY OAKS ROAD, SUITE 227", "city": "WALTHAM", "state": "MA", "zip": "02154", "phone": "7816471234"}, "mail-address": {"street1": "411WAVERLY OAKS ROAD", "street2": "SUITE 227", "city": "WALTHAM", "state": "MA", "zip": "02154"}}
text: 1
  
       As filed with the Securities and Exchange Commission on August 30, 2000
  
                                                      Registration No. 333-_______
  
  ================================================================================
  
                         SECURITIES AND EXCHANGE COMMISSION
                               WASHINGTON, D.C. 20549
  
                                  -----------------
  
                                      FORM S-8
  
                            REGISTRATION STATEMENT UNDER
                             THE SECURITIES ACT OF 1933
  
                                  NETsilicon, Inc.
               (Exact Name of Registrant as specified in its charter)
  
            Massachusetts                                          04-2826579
  (State or other jurisdiction of                               (I.R.S. Employer
   incorporation or organization)                              Identification No.)
  
                                  -----------------
  
                          411 WAVERLEY OAKS ROAD, BLDG. 227
                                  WALTHAM, MA 02452
                                   (781) 647-1234
                 (Address of Principal Executive Offices) (Zip Code)
  
                                  -----------------
  
                                  NETSILICON, INC.
                          2000 EMPLOYEE STOCK PURCHASE PLAN
                              (Full title of the plan)
  
                                  -----------------
  
                               CORNELIUS PETERSON VIII
                        PRESIDENT AND CHIEF EXECUTIVE OFFICER
                                  NETSILICON, INC.
                          411 WAVERLEY OAKS ROAD, BLDG. 227
                                  WALTHAM, MA 02452
                 (Name and Address of Agent for Service of Process)
  
                                   (781) 647-1234
            (Telephone Number, Including Area Code, of Agent For Service)
  
                                  -----------------
  
                                      Copy to:
  
                             EDWIN L. MILLER, JR., ESQ.
                           TESTA, HURWITZ & THIBEAULT, LLP
                                   125 HIGH STREET
                             BOSTON, MASSACHUSETTS 02110
                                   (617) 248-7000
  
  ================================================================================
  2
  
                           CALCULATION OF REGISTRATION FEE
  ===================================================================================================================
                                                                    Proposed
                                                                    Maximum        Proposed
                                                                    Offering       Maximum
  Title of Securities                            Amount to be      Price Per       Aggregate        Amount of
  to be Registered                                Registered         Share      Offering Price    Registration Fee(2)
  2000 Employee Stock Purchase Plan
  Common Stock (par value $.01 per share)           500,000          $25.38(1)     $12,690,000        $3,350.16
  
  ===================================================================================================================
  (1) These shares are not subject to outstanding options. The price of $25.38 per
      share, which is the average of the high and low prices reported on the
      Nasdaq National Market on August 29, 2000, is set forth solely for purposes
      of calculating the filing fee pursuant to Rule 457(c) and (h) and has been
      used for shares without a fixed exercise or purchase price.
  
  (2) Calculated pursuant to Section 6(b) of the Securities Act of 1933, as
      amended.
  
                                         2
  3
  
                                       PART I
  
                INFORMATION REQUIRED IN THE SECTION 10(a) PROSPECTUS
  
  Item 1.  PLAN INFORMATION.
           -----------------
  
           The documents containing the information specified in this Item 1 will
  be sent or given to employees as specified by Rule 428(b)(1). In accordance with
  the rules and regulations of the Securities and Exchange Commission (the
  "Commission") and the instructions to Form S-8, such documents are not being
  filed with the Commission either as part of this Registration Statement or as
  prospectuses or prospectus supplements pursuant to Rule 424.
  
  Item 2.  REGISTRANT INFORMATION AND EMPLOYEE PLAN ANNUAL INFORMATION.
           ------------------------------------------------------------
  
           The documents containing the information specified in this Item 2 will
  be sent or given to employees as specified by Rule 428(b). In accordance with
  the rules and regulations of the Commission and the instructions to Form S-8,
  such documents are not being filed with the Commission either as part of this
  Registration Statement or as prospectuses or prospectus supplements pursuant to
  Rule 424.
  
                                       PART II
  
                 INFORMATION REQUIRED IN THE REGISTRATION STATEMENT
  
  Item 3.  INCORPORATION OF DOCUMENTS BY REFERENCE.
           ----------------------------------------
  
           The following documents filed with the Commission are incorporated by
  reference in this Registration Statement:
  
  (a)      Registrant's Annual Report on Form 10-K for the year ended January 31,
           2000, as filed with the Commission pursuant to Section 13(a) or 15(d)
           of the Securities Exchange Act of 1934, as amended (the "Exchange
           Act");
  
  (b)      All other reports filed pursuant to Section 13(a) or 15(d) of the
           Exchange Act since the end of the fiscal year covered by the
           Registrant's document referred to in (a) above.
  
  (c)      The section entitled "Description of Registrant's Securities to be
           Registered" contained in the Registrant's Registration Statement on
           Form 8-A (File No. 000-26761) filed on July 20, 1999 pursuant to
           Section 12(g) of the Exchange Act.
  
           All documents subsequently filed with the Commission by the Registrant
  pursuant to Sections 13(a), 13(c), 14 and 15(d) of the Exchange Act, prior to
  the filing of a post-effective amendment which indicates that all securities
  offered herein have been sold or which deregisters all securities then remaining
  unsold, shall be deemed to be incorporated by reference in this Registration
  Statement and to be a part thereof from the date of filing of such documents.
  
                                         3
  4
  
  Item 4.  DESCRIPTION OF SECURITIES.
           --------------------------
  
           Not applicable.
  
  Item 5.  INTERESTS OF NAMED EXPERTS AND COUNSEL.
           ---------------------------------------
  
           Not applicable.
  
  Item 6.  INDEMNIFICATION OF DIRECTORS AND OFFICERS.
           ------------------------------------------
  
           The Restated Articles of Organization and the Amended and Restated
  By-Laws of the Company provide for indemnification of the Company's directors
  and officers unless such indemnification is prohibited by the Massachusetts
  Business Corporation Law. The Massachusetts Business Corporation Law generally
  permits indemnification of the Company's directors and officers for liabilities
  and expenses that they may incur in such capacities, except with respect to any
  matter that the indemnified person shall have been adjudicated in any proceeding
  not to have acted in good faith in the reasonable belief that his or her action
  was in the best interest of the Company. Reference is made to the Registrant's
  Restated Articles of Organization filed as Exhibit 3.1 to the Registrant's
  Registration Statement on Form S-1 (File No. 333-62231) and the Registrant's
  Amended and Restated By-Laws filed as Exhibit 3.3 to the Registrant's
  Registration Statement on Form S-1 (File No. 333-62231).
  
           The underwriting agreement, dated September 15, 1999, by and between
  the Registrant and the underwriters listed therein provides that the
  underwriters are obligated, under certain circumstances, to indemnify directors,
  officers and controlling persons of the Registrant against certain liabilities,
  including liabilities under the Securities Act. Reference is made to the Form of
  Underwriting Agreement filed as Exhibit 1.1 to the Registrant's Registration
  Statement on Form S-1 (File No. 333-62231).
  
           The Registrant has in effect a directors' and officers' insurance
  policy.
  
  Item 7.  EXEMPTION FROM REGISTRATION CLAIMED.
           ------------------------------------
  
           Not applicable.
  
  Item 8.  EXHIBITS.
           ---------
  
  EXHIBIT NO.                       DESCRIPTION OF EXHIBIT
  -----------                       ----------------------
  
    4.1       Specimen Certificate for shares of the Registrant's Common Stock
              (filed as Exhibit 4 to the Registrant's Registration Statement on
              Form S-1 (File No. 333-62231) and incorporated herein by reference)
  
    4.2       Restated Articles of Organization (filed as Exhibit 3.1 to the
              Registrant's Registration Statement on Form S-1 (File No. 333-62231)
              and incorporated herein by reference)
  
    4.3       Amended and Restated By-Laws of the Registrant (filed as Exhibit 3.3
              to the Registration Statement on Form S-1 (File No. 333-62231) and
              incorporated herein by reference)
  
                                         4
  5
  
    4.4       NETsilicon, Inc. 2000 Employee Stock Purchase Plan
  
    5.1       Opinion of Testa, Hurwitz & Thibeault, LLP
  
   23.1       Consent of Testa, Hurwitz & Thibeault, LLP (included in Exhibit 5.1)
  
   23.2       Consent of BDO Seidman, LLP
  
   24.1       Power of Attorney (included as part of the signature page of this
              Registration Statement)
  
  Item 9.  UNDERTAKINGS.
           -------------
  
           (a)   The undersigned Registrant hereby undertakes:
  
                 (1)  To file, during any period in which offers or sales are
                 being made, a post-effective amendment to this registration
                 statement:
  
                      (i) To include any prospectus required by Section 10(a)(3)
                      of the Securities Act of 1933;
  
                      (ii) To reflect in the prospectus any facts or events
                      arising after the effective date of the registration
                      statement (or the most recent post-effective amendment
                      thereof) which, individually or in the aggregate, represent
                      a fundamental change in the information set forth in the
                      registration statement. Notwithstanding the foregoing, any
                      increase or decrease in volume of securities offered (if the
                      total dollar value of securities offered would not exceed
                      that which was registered) and any deviation from the low or
                      high end of the estimated maximum offering range may be
                      reflected in the form of prospectus filed with the
                      Commission pursuant to Rule 424(b) if, in the aggregate, the
                      changes in volume and price represent no more than a 20
                      percent change in the maximum aggregate offering price set
                      forth in the "Calculation of Registration Fee" table in the
                      effective registration statement;
  
                      (iii) To include any material information with respect to
                      the plan of distribution not previously disclosed in the
                      registration statement or any material change to such
                      information in the registration statement;
  
                      PROVIDED, HOWEVER, that paragraphs (a)(1)(i) and (a)(1)(ii)
                      do not apply if the registration statement is on Form S-3,
                      Form S-8 or Form F-3, and the information required to be
                      included in a post-effective amendment by those paragraphs
                      is contained in periodic reports filed with or furnished to
                      the Commission by the Registrant pursuant to Section 13 or
                      Section 15(d) of the Securities Exchange Act of 1934 that
                      are incorporated by reference in the Registration Statement.
  
                                         5
  6
  
                 (2) That, for the purpose of determining any liability under the
                 Securities Act of 1933, each such post-effective amendment shall
                 be deemed to be a new registration statement relating to the
                 securities offered therein, and the offering of such securities
                 at that time shall be deemed to be the initial bona fide offering
                 thereof;
  
                 (3) To remove from registration by means of a post-effective
                 amendment any of the securities being registered which remain
                 unsold at the termination of the offering.
  
           (b)  The undersigned Registrant hereby undertakes that, for purposes of
           determining any liability under the Securities Act of 1933, each filing
           of the Registrant's annual report pursuant to Section 13(a) or Section
           15(d) of the Securities Exchange Act of 1934 (and, where applicable,
           each filing of an employee benefit plan's annual report pursuant to
           Section 15(d) of the Securities Exchange Act of 1934) that is
           incorporated by reference in the registration statement shall be deemed
           to be a new registration statement relating to the securities offered
           therein, and the offering of such securities at that time shall be
           deemed to be the initial bona fide offering thereof.
  
           (c)  Insofar as indemnification for liabilities arising under the
           Securities Act of 1933 may be permitted to directors, officers and
           controlling persons of the Registrant pursuant to the foregoing
           provisions, or otherwise, the Registrant has been advised that in the
           opinion of the Securities and Exchange Commission such indemnification
           is against public policy as expressed in the Act and is, therefore,
           unenforceable. In the event that a claim for indemnification against
           such liabilities (other than the payment by the Registrant of expenses
           incurred or paid by a director, officer or controlling person of the
           Registrant in the successful defense of any action, suit or proceeding)
           is asserted by such director, officer or controlling person in
           connection with the securities being registered, the Registrant will,
           unless in the opinion of its counsel the matter has been settled by
           controlling precedent, submit to a court of appropriate jurisdiction
           the question whether such indemnification by it is against public
           policy as expressed in the Act and will be governed by the final
           adjudication of such issue.
  
                                         6
  7
  
                                     SIGNATURES
  
           Pursuant to the requirements of the Securities Act of 1933, the
  Registrant certifies that it has reasonable grounds to believe that it meets all
  of the requirements for filing on Form S-8 and has duly caused this Registration
  Statement to be signed on its behalf by the undersigned, thereunto duly
  authorized, in the City of Waltham in the State of Massachusetts, on this 30th
  day of August, 2000.
  
                                         NETsilicon, Inc.
  
                                         By: /s/ Cornelius Peterson, VIII
                                            --------------------------------
                                            Cornelius Peterson, VIII
                                            President and Chief Executive Officer
  
                          POWER OF ATTORNEY AND SIGNATURES
  
           We, the undersigned officers and directors of NETsilicon, Inc., hereby
  severally constitute and appoint Cornelius Peterson VIII and Daniel J. Sullivan,
  and each of them singly, our true and lawful attorneys, with full power to them
  and each of them singly, to sign for us in our names in the capacities indicated
  below, any amendments to this Registration Statement on Form S-8 (including
  post-effective amendments), and to file the same, with all exhibits thereto and
  other documents in connection therewith, with the Securities and Exchange
  Commission, and generally to do all things in our names and on our behalf in our
  capacities as officers and directors to enable NETsilicon, Inc., to comply with
  the provisions of the Securities Act of 1933, as amended, hereby ratifying and
  confirming our signatures as they may be signed by our said attorneys, or any of
  them, to said Registration Statement and all amendments thereto.
  
           Pursuant to the requirements of the Securities Act of 1933, this
  Registration Statement has been signed by the following persons in the
  capacities and on the date indicated.
  SIGNATURE                               TITLE                                     DATE
  /s/ Cornelius Peterson, VIII            President, Chief Executive Officer and            August 30, 2000
  -------------------------------------   Director (Principal Executive Officer)
  Cornelius Peterson, VIII
  
  /s/ Daniel J. Sullivan                  Chief Financial Officer                           August 30, 2000
  -------------------------------------   (Principal Financial and Accounting Officer)
  Daniel J. Sullivan
  
  /s/ Michael K. Ballard                  Director                                          August 30, 2000
  -------------------------------------
  Michael K. Ballard
  
  /s/ Francis E. Girard                   Director                                          August 30, 2000
  -------------------------------------
  Francis E. Girard
  
  /s/ William Johnson                     Director                                          August 30, 2000
  -------------------------------------
  William Johnson
  
  /s/ Edward B. Roberts                   Director                                          August 30, 2000
  -------------------------------------
  Edward B. Roberts
  
  /s/ F. Grant Saviers                    Director                                          August 30, 2000
  -------------------------------------
  F. Grant Saviers
  7
  8
  
                                  INDEX TO EXHIBITS
  
  EXHIBIT NO.    DESCRIPTION OF EXHIBIT
  -----------    ----------------------
  
    4.1          Specimen Certificate for shares of the Registrant's Common Stock
                 (filed as Exhibit 4 to the Registrant's Registration Statement on
                 Form S-1 (File No. 333-62231) and incorporated herein by
                 reference)
  
    4.2          Restated Articles of Organization (filed as Exhibit 3.1 to the
                 Registrant's Registration Statement on Form S-1 (File No.
                 333-62231) and incorporated herein by reference)
  
    4.3          Amended and Restated By-Laws of the Registrant (filed as Exhibit
                 3.3 to the Registration Statement on Form S-1 (File No.
                 333-62231) and incorporated herein by reference)
  
    4.4          NETsilicon, Inc. 2000 Employee Stock Purchase Plan
  
    5.1          Opinion of Testa, Hurwitz & Thibeault, LLP
  
   23.1          Consent of Testa, Hurwitz & Thibeault, LLP (included in
                 Exhibit 5.1)
  
   23.2          Consent of BDO Seidman, LLP
  
   24.1          Power of Attorney (included as part of the signature page of
                 this Registration Statement)
  
                                         8