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                                                                     EXHIBIT 4.2

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                             CONEXANT SYSTEMS, INC.


                               4311 JAMBOREE ROAD
                             NEWPORT BEACH, CA 92660



                          REGISTRATION RIGHTS AGREEMENT



                                  MAY __, 2000


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                             CONEXANT SYSTEMS, INC.

                          REGISTRATION RIGHTS AGREEMENT


         This Registration Rights Agreement (the "Agreement") is made as of May
__, 2000, between Conexant Systems, Inc., a Delaware corporation (the "Parent")
and certain former shareholders (the "Shareholders") of Sierra Imaging, Inc., a
California corporation (the "Company") identified on EXHIBIT A hereto.

         WHEREAS:

         A. Pursuant to the terms of the Agreement and Plan of Merger dated as
of even date herewith (the "Merger Agreement"), by and among Parent, the
Company, and Griffindor Acquisition Corporation, a California corporation and
wholly owned subsidiary of Parent ("Merger Sub"), Merger Sub is being merged
with and into the Company (the "Merger"), with the Company being the surviving
corporation.

         B. In connection with the Merger, the Shareholders shall receive fully
paid and non-assessable shares (the "Shares") of common stock of Parent, par
value $1.00 per share ("Parent Common Stock").

         C. The Merger Agreement provides for the execution and delivery of this
Agreement at the closing of the transactions contemplated thereby which grants
the Shareholders certain rights to have their Shares registered under the
Securities Act of 1933, as amended.

         NOW, THEREFORE, in consideration of the premises and the mutual
covenants contained herein and other good and valuable consideration, the
receipt and sufficiency of which are hereby acknowledged, the parties hereby
agree as follows:

                                   SECTION 1

                 RESTRICTIONS ON TRANSFERABILITY OF SECURITIES;
               COMPLIANCE WITH SECURITIES ACT; REGISTRATION RIGHTS

         1.1 CERTAIN DEFINITIONS. Unless otherwise indicated, the terms in this
Agreement shall have the same meanings as those terms in the Merger Agreement.
As used in this Agreement, the following terms shall have the following
respective meanings:

         "Commission" shall mean the Securities and Exchange Commission or any
other federal agency at the time administering the Securities Act.

         "Common Stock" shall mean Parent Common Stock, par value $1.00 per
share.

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         "Holder" shall mean (i) the Shareholders and (ii) any person holding
Registrable Securities to whom the rights under this Section 1 have been
transferred in accordance with Section 1.8 hereof.

         "Registrable Securities" means the Shares until such time that such
securities have been (i) effectively registered under the Securities Act and
disposed of pursuant to an effective Registration Statement, or (ii) sold in a
single transaction exempt from the registration and prospectus delivery
requirements of the Securities Act so that all transfer restrictions and
restrictive legends with respect thereto are removed upon the consummation of
such sale.

         The terms "register," "registered" and "registration" refer to a
registration effected by preparing and filing a registration statement in
compliance with the Securities Act, and the declaration or ordering of the
effectiveness of such registration statement.

         "Registration Expenses" shall mean all expenses, except as otherwise
stated below, incurred by Parent in complying with Section 1.2 hereof,
including, without limitation, all registration, qualification and filing fees,
printing expenses, escrow fees, fees and disbursements of counsel for Parent,
blue sky fees and expenses, the expense of any special audits incident to or
required by any such registration.

         "Securities Act" shall mean the Securities Act of 1933, as amended, or
any similar federal statute and the rules and regulations of the Commission
thereunder, all as the same shall be in effect at the time.

         "Selling Expenses" shall mean all underwriting discounts, selling
commissions and stock transfer taxes applicable to the securities registered by
the Holders and, except as set forth above, all reasonable fees and
disbursements of counsel for any Holder.

         "Shares" shall mean the shares of Common Stock of Parent, par value
$1.00 per share, issued to the Shareholders pursuant to the Merger Agreement,
including the Escrow Shares (as defined in the Merger Agreement) and any other
securities issued in respect of such securities upon any stock split, stock
dividend, recapitalization, merger, consolidation or similar event.

         1.2 MANDATORY REGISTRATION. Parent shall prepare within a reasonable
time but in any event within forty five (45) days after the closing of the
Merger file with the Commission a registration statement (the "Registration
Statement") on Form S-3 (or, if Form S-3 is not then available to Parent, on
such form of registration statement as is then available to effect a
registration for resale of the Registrable Securities, subject to the Holder's
consent) covering the resale of the Shares by the Holders. Parent shall use its
commercially reasonable efforts to cause the Registration Statement to be
declared effective no later than 90 days after the issuance of the Shares (the
"Effective Date").

         1.3 EXPENSES OF REGISTRATION. All Registration Expenses incurred in
connection with all registrations pursuant to Section 1.2 shall be borne by
Parent. Unless otherwise stated, all Selling Expenses and all other Registration
Expenses shall be borne by the Holders of such securities pro rata on the basis
of the number of shares so registered.


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         1.4 REGISTRATION PROCEDURES. At its expense Parent will:

                  (a) Prepare and file with the Commission the Registration
Statement with respect to the Shares and use its best efforts to cause such
Registration Statement to become effective as soon as possible after the filing
thereof, and keep the Registration Statement effective until the sale of all
Registrable Securities has been completed.

                  (b) Furnish to the Holders participating in such registration
and to the underwriters of the securities being registered, if any, such
reasonable number of copies of the registration statement, preliminary
prospectus, final prospectus and such other documents as such underwriters may
reasonably request in order to facilitate the public offering of such
securities.

         1.5 INDEMNIFICATION.

                  (a) Parent will indemnify each Holder, each of its officers
and directors and partners, and each person controlling such Holder within the
meaning of Section 15 of the Securities Act, with respect to which registration,
qualification or compliance has been effected pursuant to this Section 1, and
each underwriter, if any, and each person who controls any underwriter within
the meaning of Section 15 of the Securities Act, against all expenses, claims,
losses, damages or liabilities (or actions in respect thereof), including any of
the foregoing incurred in settlement of any litigation, commenced or threatened,
arising out of or based on any untrue statement (or alleged untrue statement) of
a material fact contained in any registration statement, prospectus, offering
circular or other document, or any amendment or supplement thereto, incident to
any such registration, qualification or compliance, or based on any omission (or
alleged omission) to state therein a material fact required to be stated therein
or necessary to make the statements therein, in light of the circumstances in
which they were made, not misleading, or any violation by Parent of the
Securities Act, the Exchange Act, state securities law or any rule or regulation
promulgated under such laws applicable to Parent in connection with any such
registration, qualification or compliance, and within a reasonable period Parent
will reimburse each such Holder, each of its officers and directors, and each
person controlling such Holder, each such underwriter and each person who
controls any such underwriter, for any legal and any other expenses reasonably
incurred in connection with investigating, preparing or defending any such
claim, loss, damage, liability or action; provided that Parent will not be
liable in any such case to the extent that any such claim, loss, damage,
liability or expense arises out of or is based on any untrue statement or
omission or alleged untrue statement or omission, made in reliance upon and in
conformity with written information furnished to Parent for use in the
Registration Statement.


                  (b) Each Holder will, if Registrable Securities held by such
Holder are included in the securities as to which such registration,
qualification or compliance is being effected, indemnify Parent, each of its
directors and officers, each underwriter, if any, of Parent's securities covered
by such a registration statement, each person who controls Parent or such
underwriter within the meaning of Section 15 of the Securities Act, and each
other such Holder, each of its officers and directors and each person
controlling such Holder within the meaning of Section 15 of the Securities Act,
against all claims, losses, damages and liabilities (or actions in respect
thereof) arising out of or based on any untrue statement (or alleged untrue
statement) of a material fact contained in any such


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registration statement, prospectus, offering circular or other document, or any
omission (or alleged omission) to state therein a material fact required to be
stated therein or necessary to make the statements therein not misleading, and
within a reasonable period will reimburse Parent, such Holders, such directors,
officers, persons, underwriters or control persons for any legal or any other
expenses reasonably incurred in connection with investigating or defending any
such claim, loss, damage, liability or action, in each case to the extent, but
only to the extent, that such untrue statement (or alleged untrue statement) or
omission (or alleged omission) is made in such registration statement,
prospectus, offering circular or other document in reliance upon and in
conformity with written information furnished to Parent for use in the
Registration Statement. Notwithstanding the foregoing, the liability of each
Holder under this subsection (b) shall be limited in an amount equal to the
gross proceeds before expenses and commissions to each Holder received for the
shares sold by such Holder, unless such liability arises out of or is based on
willful misconduct by such Holder.

                  (c) Each party entitled to indemnification under this Section
1.5 (the "Indemnified Party") shall give notice to the party required to provide
indemnification (the "Indemnifying Party") promptly after such Indemnified Party
has actual knowledge of any claim as to which indemnity may be sought, and shall
permit the Indemnifying Party to assume the defense of any such claim or any
litigation resulting therefrom, provided that counsel for the Indemnifying
Party, who shall conduct the defense of such claim or litigation, shall be
approved by the Indemnified Party (whose approval shall not unreasonably be
withheld), and the Indemnified Party may participate in such defense at such
party's expense, and provided further that the failure of any Indemnified Party
to give notice as provided herein shall not relieve the Indemnifying Party of
its obligations under this Section 1 unless the failure to give such notice is
materially prejudicial to an Indemnifying Party's ability to defend such action
and provided further, that the Indemnifying Party shall not assume the defense
for matters as to which there is a conflict of interest or separate and
different defenses. No Indemnifying Party, in the defense of any such claim or
litigation, shall, except with the consent of each Indemnified Party, consent to
entry of any judgment or enter into any settlement which does not include as an
unconditional term thereof the giving by the claimant or plaintiff to such
Indemnified Party of a release from all liability in respect to such claim or
litigation.

         1.6 INFORMATION BY HOLDER. The Holder or Holders of Registrable
Securities included in any registration shall furnish to Parent such information
regarding such Holder or Holders, the Registrable Securities held by them and
the distribution proposed by such Holder or Holders as Parent may request in
writing and as shall be required in connection with any registration,
qualification or compliance referred to in this Section 1.

         1.7 TRANSFER OF REGISTRATION RIGHTS. The rights to cause Parent to
register securities granted Holders under Section 1.2 may be assigned to a
transferee or assignee which acquires at least 1000 shares of Registrable
Securities in connection with any transfer or assignment of Registrable
Securities by the Holders.


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                                    SECTION 2

                                  MISCELLANEOUS

         2.1 GOVERNING LAW. This Agreement shall be governed in all respects by
the internal laws of the State of California.

         2.2 SURVIVAL. The covenants and agreements made herein shall survive
the closing of the transactions contemplated hereby.

         2.3 SUCCESSORS AND ASSIGNS. Except as otherwise provided herein, the
provisions hereof shall inure to the benefit of, and be binding upon, the
successors, assigns, heirs, executors and administrators of the parties hereto.

         2.4 ENTIRE AGREEMENT; AMENDMENT. This Agreement and the Merger
Agreement constitute the full and entire understanding and agreement between the
parties with regard to the subjects hereof and thereof, and no party shall be
liable or bound to any other party in any manner by any warranties,
representations or covenants except as specifically set forth herein or therein.
Except as expressly provided herein, neither this Agreement nor any term hereof
may be amended, waived, discharged or terminated other than by a written
instrument signed by the party against whom enforcement of any such amendment,
waiver, discharge or termination is sought; provided, however, that holders of a
majority of the Registrable Securities may, with Parent's prior written consent,
waive, modify or amend on behalf of all holders, any provisions hereof.

         2.5 NOTICES, ETC. All notices and other communications required or
permitted hereunder shall be in writing and shall be mailed by registered or
certified mail, postage prepaid, telecopied or otherwise delivered by hand or by
messenger, addressed (a) if to a Holder, at such address as such Holder shall
have furnished Parent in writing, or, until any such holder so furnishes an
address to Parent, then to and at the address of the last Holder who has so
furnished an address to Parent, or (b) if to Parent, one copy should be sent to
its address set forth on the cover page of this Agreement and addressed to the
attention of the President, or at such other address as Parent shall have
furnished to the Holders.

         Each such notice or other communication shall for all purposes of this
Agreement be treated as effective or having been given when delivered if
delivered personally, or, if sent by mail, at the earlier of its receipt or 72
hours after the same has been deposited in a regularly maintained receptacle for
the deposit of the United States mail, addressed and mailed as aforesaid.

         2.6 DELAYS OR OMISSIONS. Except as expressly provided herein, no delay
or omission to exercise any right, power or remedy accruing to any party to this
Agreement upon any breach or default of any other party under this Agreement,
shall impair any such right, power or remedy of such nondefaulting party nor
shall it be construed to be a waiver of any such breach or default, or an
acquiescence therein, or of or in any similar breach or default thereafter
occurring; nor shall any waiver of any single breach or default be deemed a
waiver of any other breach or default theretofore or thereafter occurring. Any
waiver, permit, consent or approval of any kind or character on the part of any
party of any breach or default under this Agreement, or any waiver on the part
of any holder of any provisions or conditions of this Agreement, must be in
writing and shall be effective only to the extent specifically set forth in such
writing. All remedies, either under this Agreement or by law or otherwise
afforded to any party to this Agreement, shall be cumulative and not
alternative.


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         2.7 COUNTERPARTS. This Agreement may be executed in any number of
counterparts, each of which shall be enforceable against the parties actually
executing such counterparts, and all of which together shall constitute one
instrument.

         2.8 SEVERABILITY. In the event that any provision of this Agreement
becomes or is declared by a court of competent jurisdiction to be illegal,
unenforceable or void, this Agreement shall continue in full force and effect
without said provision; provided that no such severability shall be effective if
it materially changes the economic benefit of this Agreement to any party.

         2.9 TITLES AND SUBTITLES. The titles and subtitles used in this
Agreement are used for convenience only and are not considered in construing or
interpreting this Agreement.


            (THE REMAINDER OF THIS PAGE IS INTENTIONALLY LEFT BLANK)


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         The foregoing Agreement is hereby executed as of the date first above
written.


                                        "PARENT"

                                        CONEXANT SYSTEMS, INC.
                                        a Delaware Corporation


                                        By:
                                             -----------------------------------
                                             Name:
                                             Title:


                                        "SHAREHOLDER"



                                        By:
                                             -----------------------------------
                                             Name:
                                             Title:



                (SIGNATURE PAGE TO REGISTRATION RIGHTS AGREEMENT)


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                                    EXHIBIT A

                      SHAREHOLDERS OF SIERRA IMAGING, INC.



Shareholder: