EXHIBIT 8.1


                   FORM OF TAX OPINION OF COUNSEL TO PARENT




                                 August __, 1996


C-Cube Microsystems Inc.
1778 McCarthy Blvd.
Milpitas, California  95035

Ladies and Gentlemen:

     We have acted as counsel for C-Cube Microsystems Inc., a Delaware 
corporation ("C-Cube") in connection with the preparation and execution of 
the Agreement and Plan of Reorganization dated as of May __, 1996, as amended 
on July 25, 1996, and July 26, 1996 (the "Reorganization Agreement") by and 
among C-Cube, C-Cube Acquisition Corp., a wholly-owned subsidiary of C-Cube 
incorporated in Delaware ("Merger Sub"), and DiviCom Inc., a Delaware 
corporation ("DiviCom").  Pursuant to the Reorganization Agreement, DiviCom 
will merge with and into Merger Sub (the "Merger").  Unless otherwise 
defined, capitalized terms referred to herein have the meanings set forth in 
the Reorganization Agreement.  All section references, unless otherwise 
indicated, are to the Internal Revenue Code of 1986, as amended (the "Code").

     You have requested our opinion regarding certain United States federal 
income tax consequences of the Merger.  In delivering this opinion, we have 
reviewed and relied upon the facts, statements, descriptions and 
representations set forth in the Reorganization Agreement (including 
Exhibits) and such other documents pertaining to the Merger as we have deemed 
necessary or appropriate. We have also relied upon certificates of officers 
of C-Cube and DiviCom included as exhibits to the Reorganization Agreement 
(the "Officers' Certificates") and representations made by certain 
shareholders of DiviCom in "Affiliate Agreements."

     In connection with rendering this opinion, we have also assumed (without 
any independent investigation) that:

     1.   Original documents (including signatures) are authentic, documents 
submitted to us as copies conform to the original documents, and there has 
been (or will be by the Effective Time) due execution and delivery of all 
documents where due execution and delivery are prerequisites to effectiveness 
thereof;

     2.   Any statement made in any of the documents referred to herein,"to 
the best of the knowledge" of any person or party is correct without such 
qualification;

     3.   All statements, descriptions and representations contained in any 
of the documents referred to herein or otherwise made to us are true and 
correct in all material respects and no actions have been (or will be) taken 
which are inconsistent with such representations; 

     4.   The Merger will be reported by C-Cube and DiviCom on their 
respective federal income tax returns in a manner consistent with the opinion 
set forth below;



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August __, 1996
Page 2

     5.   The Merger will be consummated pursuant to the Reorganization 
Agreement and will be effective under the law of the State of Delaware;

     6.   At the Effective Time of the Merger, the aggregate fair market 
value of the C-Cube Common Stock to be received in the Merger will be no less 
than forty-five percent (45%) of the aggregate fair market value of all of 
the capital stock of DiviCom outstanding immediately prior to the Merger.

     7.   There is no plan or intention on the part of the stockholders of 
DiviCom to sell, exchange, or otherwise dispose of a number of shares of 
C-Cube Common Stock to be received in the Merger that would reduce the 
DiviCom stockholders' ownership of C-Cube Common Stock to a number of shares 
having an aggregate fair market value, as of the Effective Time, of less than 
forty-five percent (45%) of the aggregate fair market value of all of the 
capital stock of DiviCom outstanding immediately prior to the consummation of 
the Merger.  Shares of the DiviCom capital stock (a) with respect to which 
dissenters' rights are exercised in the Merger, (b) which are exchanged for 
cash in lieu of fractional shares of C-Cube Common Stock or (c) which are 
sold, redeemed or disposed of in a transaction that is in contemplation of or 
related to the Merger, shall be considered shares of capital stock of DiviCom 
which are exchanged in the Merger for shares of C-Cube Common Stock which are 
then disposed of pursuant to a plan; and

     8.   DiviCom will have received an opinion of Fenwick & West 
substantially identical in form and substance to this opinion.

     Based on our examination of the foregoing items and subject to the 
assumptions, exceptions, limitations and qualifications set forth herein, we 
are of the opinion that, if the Merger is consummated in accordance with the 
Reorganization Agreement (and without any waiver, breach or amendment of any 
of the provisions thereof) and the statements set forth in the Officers' 
Certificates and the Affiliate Agreements are true and correct as of the 
Effective Time, then for federal income tax purposes:

          (a)  The Merger will constitute a reorganization within the meaning 
of Section 368(a) of the Code.

          (b)  The discussion entitled "Certain Federal Income Tax 
Considerations" in the Prospectus constituting a part of the Registration 
Statement, insofar as it related to statements of law or legal conclusions, 
states the opinion of this firm.

     This opinion represents and is based upon our best judgment regarding 
the application of federal income tax laws arising under the Code, existing 
judicial decisions, administrative regulations and published rulings and 
procedures.  Our opinion is not binding upon the Internal Revenue Service or 
the courts, and there is no assurance that the Internal Revenue Service will 
not successfully assert a contrary position.  Furthermore, no assurance can 
be given that future legislative, judicial or administrative changes,




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August __, 1996
Page 3

on either a prospective or retroactive basis, would not adversely affect the 
accuracy of the conclusions stated herein.  Nevertheless, we undertake no 
responsibility to advise you of any new developments in the application or 
interpretation of the federal income tax laws occurring subsequent to the 
date of this opinion.

     This opinion addresses only the classification of the Merger as a 
reorganization under Section 368(a) of the Code, and does not address any 
other federal, state, local or foreign tax consequences that may result from 
the Merger or any other transaction (including any transaction undertaken in 
connection with the Merger).

     No opinion is expressed as to any transaction other than the Merger as 
described in the Reorganization Agreement or to any transaction whatsoever, 
including the Merger, if all the transactions described in the Reorganization 
Agreement are not consummated in accordance with the terms of such 
Reorganization Agreement and without waiver or breach of any material 
provision thereof or if all of the representations, warranties, statements 
and assumptions upon which we relied are not true and accurate at all 
relevant times.  In the event any one of the statements, representations, 
warranties or assumptions upon which we have relied to issue this opinion is 
incorrect, our opinion might be adversely affected and may not be relied upon.

     We hereby consent to the filing of this opinion as an exhibit to the 
Registration Statement filed on Form S-4 with the Securities and Exchange 
Commission and we further consent to all references to us in the Registration 
Statement.

                              Very truly yours,

                              WILSON SONSINI GOODRICH & ROSATI
                              Professional Corporation