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                                  UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549
                -------------------------------------------------
                                   FORM 10-K/A
                ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF
                       THE SECURITIES EXCHANGE ACT OF 1934

For the Fiscal Year Ended December 31, 2001      Commission File Number 0-13071

                             INTERPHASE CORPORATION
             (Exact name of registrant as specified in its charter)

             TEXAS                                          75-1549797
  (State or other jurisdiction of                        (I.R.S. Employer
  incorporation or organization)                        Identification No.)

                        13800 SENLAC, DALLAS, TEXAS 75234
              (Address of principal executive offices and zip code)
               Registrant's telephone number, including area code:
                (214) 654-5000 Securities registered pursuant to
                            Section 12(b) of the Act:

                                      NONE
           Securities registered pursuant to Section 12(g) of the Act:

                                 TITLE OF CLASS
                          Common Stock, $.10 par value

Indicate by check mark whether the registrant (1) has filed all reports required
by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the
preceding 12 months (or for such shorter period that the registrant was required
to file such reports), and (2) has been subject to such filing requirements for
the past 90 days.                                          Yes  X     No
                                                               ---       ---

Indicate by check mark if disclosure of delinquent filers pursuant to Item 405
of Regulation S-K is not contained herein, and will not be contained, to the
best of registrant's knowledge, in definitive proxy or information statements
incorporated by reference in Part III of this Form 10-K or any amendment to this
10-K. [X]

The aggregate market value of the voting stock held by non-affiliates of the
registrant on March 4, 2002 was approximately $27,312,000. As of March 4, 2002,
registrant had 5,598,805 shares of Common Stock outstanding.

                       DOCUMENTS INCORPORATED BY REFERENCE

Parts of the following documents are incorporated by reference into this annual
report on Form 10-K Report: Portions of the Definitive Proxy Statement for
Annual Meeting of Shareholders to be held on May 1, 2002 (Part III).
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This Form 10-K/A amends the Company's Form 10-K405 filed on March 26, 2002 as
follows:

ITEM 12. SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND MANAGEMENT

The following table sets forth certain information as to the number of shares of
Common Stock of the Company beneficially owned as of March 4, 2002 by (i) each
person who is known to the Company to own beneficially more than 5% of the
outstanding Common Stock of the Company, (ii) certain executive officers and
each director of the Company and (iii) all executive officers and directors as a
group. Each of the owners named below has sole voting and investment power with
respect to the shares of Common Stock beneficially owned by him or it unless
otherwise indicated.

<Table>
<Caption>
  Name and address of                       Amount and Nature of                  Percent of
   Beneficial Owner                         Beneficial Ownership                     Class
  ------------------                        --------------------                  ----------
<S>                                         <C>                                   <C>
Gregory B. Kalush                                     329,830     (1)(2)                5.9%
S. Thomas Thawley                                     276,959      (1)                  4.9%
Steven P. Kovac                                        93,335      (1)                  1.7%
David H. Segrest                                       52,000      (1)                  0.9%
Paul N. Hug                                            48,000      (1)                  0.9%
James F. Halpin                                        42,000      (1)                  0.8%
William R. Voss                                        41,000      (1)                  0.7%
Randall D. Ledford                                     20,000      (1)                  0.4%

All executive officers and directors
as a group (8 persons)                                903,124      (3)                 16.1%

Royce & Associates, Inc.
1414 Avenue of the Americas
New York, NY 10019                                    446,000                           8.0%

Joseph Harrosh
40900 Grimmer Blvd
Freemont, CA 94538                                    353,400                           6.3%
</Table>

(1)      Includes vested options to purchase Common Stock with exercise prices
         ranging from $4.38-$23.00 per share (fair market value on the
         respective dates of grant) as follows: Mr. Kalush, 248,501 shares; Mr.
         Thawley, 50,334 shares; Mr. Kovac, 93,335 shares; Mr. Segrest, 47,000
         shares; Mr. Hug, 47,000 shares; Mr. Halpin, 35,000 shares; Mr. Voss,
         40,000 shares and Mr. Ledford, 20,000 shares.

(2)      Includes beneficial ownership of shares due to voting rights on shares
         held by Motorola (81,329 shares).

(3)      Includes 581,170 shares that may be acquired upon exercise of vested
         stock options.



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                                   SIGNATURES

Pursuant to the requirements of Section 13 or 15(d) of the Securities Exchange
Act of 1934, the registrant has duly caused this report to be signed on its
behalf by the undersigned, thereunto duly authorized.

                                       INTERPHASE CORPORATION


Date: April 22, 2002                   By:  /s/ Gregory B. Kalush
                                          -------------------------
                                          Gregory B. Kalush
                                          Chairman of the Board,
                                          Chief Executive Officer and President

Pursuant to the requirements of the Securities Exchange Act of 1934, this report
has been signed below by the following persons on behalf of the registrant and
in the capacities indicated on April 22, 2002.

<Table>
<Caption>
                          Name                                                Title
                          ----                                                -----
<S>                                                           <C>
                    /s/ Gregory B. Kalush                     Chairman of the Board,
          ---------------------------------------             Chief Executive Officer and President
                  Gregory B. Kalush                           (Principal executive officer)

                     /s/ Steven P. Kovac                      Chief Financial Officer, Treasurer and
          ---------------------------------------             Vice President of Finance
                       Steven P. Kovac                        (Principal financial officer)

                  /s/ James F. Halpin                                  Director
          ---------------------------------------
                  James F. Halpin

                     /s/ Paul N. Hug                                   Director
          ---------------------------------------
                        Paul N. Hug

                  /s/ Randall D. Ledford                               Director
          ---------------------------------------
                     Randall D. Ledford

                  /s/ David H. Segrest                                 Director
          ---------------------------------------
                     David H. Segrest

                   /s/ S. Thomas Thawley                               Vice Chairman, Director
          ---------------------------------------                      and Secretary
                      S. Thomas Thawley

                   /s/ William R. Voss                                 Director
          ---------------------------------------
                      William R. Voss
</Table>





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