<PAGE>
--------------------------------------------------------------------------------

                                  UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION

                              WASHINGTON, DC 20549


                                    FORM 10-Q

                   QUARTERLY REPORT UNDER SECTIONS 13 OR 15(d)

                     OF THE SECURITIES EXCHANGE ACT OF 1934


   For the Quarter Ended March 31, 2002        Commission File Number 0-13071


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

               TEXAS                            75-1549797
     (State of incorporation)       (IRS Employer Identification No.)


                        13800 SENLAC, DALLAS, TEXAS 75234
                    (Address of principal executive offices)

                                 (214)-654-5000
              (Registrant's telephone number, including area code)

                                   ----------

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 a much 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 the number of shares outstanding of each of the issuer's classes of
common stock, as of the latest practicable date.

                Class                               Outstanding at May 10, 2002
                -----                               ---------------------------

    Common Stock, $.10 par value                              5,476,809

--------------------------------------------------------------------------------
<PAGE>





                             INTERPHASE CORPORATION

                                      INDEX


<Table>

<S>                                                                                    <C>
PART I -FINANCIAL INFORMATION

         Item 1.  Consolidated Interim Financial Statements

                  Consolidated Balance Sheets as of March 31, 2002
                  and December 31, 2001                                                    3

                  Consolidated Statements of Operations for the three months
                  ended March 31, 2002 and 2001                                            4

                  Consolidated Statements of Cash Flows for the three months
                  ended March 31, 2002 and 2001                                            5

                  Notes to Consolidated Interim Financial Statements                     6-9

         Item 2.  Management's Discussion and Analysis of
                  Financial Condition and Results of Operations                        10-13


PART II - OTHER INFORMATION

         Item 4.  Submission of Matters to a Vote of Security Holders                     14

         Item 6.  Reports on Form 8-K and Exhibits                                        14

                  Signature                                                               15
</Table>



                                       2
<PAGE>



INTERPHASE CORPORATION
CONSOLIDATED BALANCE SHEETS
(in thousands, except number of share data)

<Table>
<Caption>
                                                                 (unaudited)
                                                                   Mar. 31,     Dec. 31,
ASSETS                                                               2002         2001
                                                                 -----------   ----------
<S>                                                              <C>           <C>
Cash and cash equivalents                                        $   10,606    $   10,415
Marketable securities                                                 5,232         5,216
Restricted cash                                                       3,500         3,500

Trade accounts receivable, less allowances for uncollectible
     accounts and returns of $306 and $370, respectively              4,613         5,046
Inventories                                                           5,489         6,655
Prepaid expenses and other current assets                               446           480
Income taxes receivable                                               3,530         2,476
Deferred income taxes                                                 1,675         1,636
                                                                 ----------    ----------
     Total current assets                                            35,091        35,424

Machinery and equipment                                               6,125         6,117
Leasehold improvements                                                2,936         2,936
Furniture and fixtures                                                  541           543
                                                                 ----------    ----------
                                                                      9,602         9,596
Less-accumulated depreciation and amortization                       (8,827)       (8,653)
                                                                 ----------    ----------
                                                                 ----------    ----------
     Total property and equipment, net                                  775           943

Capitalized software, net                                               301           335
Deferred income taxes, net                                            1,806         2,373
Other assets                                                            187           168
                                                                 ----------    ----------
     Total assets                                                $   38,160    $   39,243
                                                                 ==========    ==========
LIABILITIES AND SHAREHOLDERS' EQUITY
     LIABILITIES
Accounts payable                                                 $      870    $      921
Deferred revenue                                                        131           110
Accrued liabilities                                                   1,556         1,615
Accrued compensation                                                  1,127         1,177
                                                                 ----------    ----------
     Total current liabilities                                        3,684         3,823

Long term debt                                                        3,500         3,500
                                                                 ----------    ----------
     Total liabilities                                                7,184         7,323

     COMMITMENTS AND CONTINGENCIES
Common stock redeemable; 81,329 and 121,996 shares,
    respectively                                                        508           762

     SHAREHOLDERS' EQUITY
Common stock, $.10 par value; 100,000,000 shares
    authorized; 5,517,476 and  5,518,476 shares issued and
    outstanding, respectively                                           552           552
Additional paid in capital                                           37,316        37,324
Retained deficit                                                     (6,960)       (6,394)
Cumulative other comprehensive loss                                    (440)         (324)
                                                                 ----------    ----------
     Total shareholders' equity                                      30,468        31,158
                                                                 ----------    ----------
     Total liabilities and shareholders' equity                  $   38,160    $   39,243
                                                                 ==========    ==========
</Table>

        The accompanying notes are an integral part of these consolidated
                              financial statements.


                                       3
<PAGE>



INTERPHASE CORPORATION
CONSOLIDATED STATEMENTS OF OPERATIONS
(in thousands except per share amounts)
(unaudited)

<Table>
<Caption>
                                             Three Months Ended Mar. 31,
                                             ---------------------------
                                                2002            2001
                                             ----------      -----------
<S>                                          <C>             <C>
Revenues                                     $    6,300      $    9,951
Cost of sales                                     3,808           4,891
                                             ----------      ----------
Gross margin                                      2,492           5,060
                                             ----------      ----------
Research and development                          1,649           2,213
Sales and marketing                               1,371           2,050
General and administrative                          754           1,095
                                             ----------      ----------
   Total operating expenses                       3,774           5,358
                                             ----------      ----------
Operating loss                                   (1,282)           (298)

Interest income, net                                193              83
Other income (expense), net                          56             (37)
                                             ----------      ----------
Loss before income taxes                         (1,033)           (252)

Income tax benefit                                 (467)            (64)
                                             ----------      ----------
 Net loss                                    $     (566)     $     (188)
                                             ==========      ==========

Net loss per share
       Basic                                 $    (0.10)     $    (0.03)
                                             ----------      ----------
       Diluted                               $    (0.10)     $    (0.03)
                                             ----------      ----------
Weighted average common shares                    5,607           5,758
                                             ----------      ----------
Weighted average common and
dilutive shares                                   5,607           5,758
                                             ----------      ----------
</Table>

              The accompanying notes are an integral part of these
                       consolidated financial statements.




                                       4
<PAGE>


INTERPHASE CORPORATION
CONSOLIDATED STATEMENTS OF CASH FLOWS
(in thousands)
(unaudited)

<Table>
<Caption>

                                                                      Three Months ended Mar. 31,
                                                                      ---------------------------
                                                                         2002            2001
                                                                      ----------      -----------
<S>                                                                   <C>             <C>
CASH FLOW FROM OPERATING ACTIVITIES:
  Net loss                                                            $     (566)     $     (188)
  Adjustment to reconcile net loss to net cash provided by
  operating activities:
  Depreciation and amortization
                                                                             230             567
  Deferred income taxes
  Tax benefit from stock option exercises                                    528              47
                                                                              --              75
   Change in assets and liabilities:
       Trade accounts receivable                                             433           4,684
       Inventories                                                         1,166            (632)
       Prepaid expenses and other current assets                              34             192
       Income taxes receivable                                            (1,054)             --
       Other assets                                                          (19)             62
       Accounts payable, deferred revenue and accrued liabilities            (89)           (507)
       Accrued compensation                                                  (50)           (866)
       Income tax payable                                                     --             (62)
                                                                      ----------      ----------
   Net adjustments                                                         1,179           3,560
                                                                      ----------      ----------
       Net cash provided by operating activities                             613           3,372

CASH FLOWS FROM INVESTING ACTIVITIES:
   Additions to property, equipment, capitalized software and
   leasehold improvements                                                    (79)            (49)
   Proceeds from sale of marketable securities                               304           4,286
   Purchases of marketable securities, net of unrealized holding
   period gain or loss                                                      (385)         (4,473)
                                                                      ----------      ----------
       Net cash used by investing activities
                                                                            (160)           (236)
CASH FLOWS FROM FINANCING ACTIVITIES:
   Payments on debt                                                           --            (567)
   Purchase of redeemable common stock                                      (254)           (254)
   Purchase of common stock                                                   (8)             --
   Proceeds from the exercise of stock options                                --             123
                                                                      ----------      ----------
       Net cash used by financing activities                                (262)           (698)
                                                                      ----------      ----------
Net increase in cash and cash equivalents                                    191           2,438
Cash and cash equivalents at beginning of period                          10,415          10,587
                                                                      ----------      ----------
Cash and cash equivalents at end of period                            $   10,606      $   13,025
                                                                      ==========      ==========
Supplemental Disclosure of Cash Flow Information:
Income taxes paid                                                     $        7      $       --
Interest paid                                                         $       23      $      120
</Table>

              The accompanying notes are an integral part of these
                       consolidated financial statements.



                                       5
<PAGE>





               NOTES TO CONSOLIDATED INTERIM FINANCIAL STATEMENTS


1. BASIS OF PRESENTATION

Interphase Corporation and subsidiaries ("Interphase" or the "Company") designs,
develops, manufactures, markets and supports high-performance connectivity
products utilizing advanced technologies being used in next-generation
telecommunication networks and enterprise data/storage networks. Interphase's
products include telecom server communication controllers, server-based adapter
cards, network operating system device drivers, software development tools and
management software applications.

The accompanying consolidated interim financial statements include the accounts
of Interphase Corporation and its wholly owned subsidiaries. Significant
intercompany accounts and transactions have been eliminated.

While the accompanying interim financial statements are unaudited, they have
been prepared by the Company pursuant to the rules and regulations of the
Securities and Exchange Commission. In the opinion of the Company, all material
adjustments and disclosures necessary to fairly present the results of such
periods have been made. Certain information and footnote disclosures normally
included in financial statements prepared in accordance with accounting
principles generally accepted in the United States have been condensed or
omitted pursuant to the rules and regulations of the Securities and Exchange
Commission. These financial statements should be read in conjunction with the
consolidated financial statements and notes thereto for the year ended December
31, 2001.

Certain prior period amounts have been reclassified to conform with the 2002
presentation.

The preparation of financial statements, in conformity with accounting
principles generally accepted in the United States, requires Company management
to make estimates and assumptions that affect the reported amounts of assets and
liabilities and disclosure of contingent assets and liabilities at the date of
the financial statements and the reported amounts of revenues and expenses
during the reporting period. Actual results could differ from those estimates.
Areas involving significant estimates are the allowance for bad debts, warranty
reserves, allowance for returns and inventory valuation.

2. CREDIT FACILITY

The Company has a $5 million revolving credit facility with a bank. The
revolving credit facility matures on June 30, 2003 and is secured throughout the
term of the credit facility by a ninety-day certificate of deposit issued by the
bank in the principal amount equal to the stated principal amount of the
promissory note. The certificate of deposit is reflected as restricted cash on
the accompanying balance sheet. The credit facility bears interest at the rate
of approximately 1% per annum above the certificate of deposit rate, which is
currently 1.44%, and includes certain restrictive covenants including, among
others, a tangible net worth restriction. As of March 31, 2002,


                                       6
<PAGE>

the Company was in compliance with all restrictive covenants included in the
revolving credit facility. At March 31, 2002, the Company had borrowings of $3.5
million and availability under the revolving credit facility was $1.5 million.

3. COMPREHENSIVE INCOME

The following table shows the Company's comprehensive income (in thousands):

<Table>
<Caption>
                                                         Three months ended March 31,
                                                           2002                2001
                                                         --------            --------
<S>                                                      <C>                 <C>
Net loss                                                 $   (566)           $   (188)
Other comprehensive income:
         Unrealized holding gain arising during
         period, net of tax                                    65                 101
         Foreign currency translation adjustment             (181)               (131)
                                                         --------            --------
Comprehensive (loss)                                     $   (682)           $   (218)
                                                         ========            ========
</Table>

4. NET INCOME PER COMMON AND COMMON DILUTIVE SHARE

Diluted earnings per share consist only of the dilutive impact of stock options,
using the treasury stock method. Due to the Company's net losses for the periods
presented, the effect of dilutive securities would have been antidilutive.
Options that would have otherwise been included in the calculation of diluted
earnings per common share were 51,906 and 170,164 stock options for the three
month periods ended March 31, 2002 and 2001, respectively.

5. SEGMENT INFORMATION

The Company is principally engaged in the design, development, and manufacturing
of high-performance connectivity products utilizing advanced technologies being
used in next generation telecommunication networks and enterprise data/storage
networks. Except for revenue performance, which is monitored by product line,
the chief operating decision-makers review financial information presented on a
consolidated basis, for purposes of making operating decisions and assessing
financial performance. Accordingly, the Company considers itself to be in a
single industry segment.

Geographic revenue and long lived assets related to North America and other
foreign countries as of and for the three-month periods ended March 31, 2002 and
2001 are as follows: (in thousands)

<Table>
<Caption>
                                  Three months ended March 31,
Revenue                             2002                2001
-------                          ----------          ----------
<S>                              <C>                 <C>
North America                    $    4,048          $    8,235
Europe                                1,440               1,438
Pac Rim                                 812                 278
                                 ----------          ----------
Total                            $    6,300          $    9,951
                                 ==========          ==========
</Table>


                                       7
<PAGE>

Geographic long-lived assets consist of property and equipment and capitalized
software, net of the related accumulated depreciation and amortization. (in
thousands)

<Table>
<Caption>
Long lived assets             March 31, 2002     December 31, 2001
-----------------             --------------     -----------------
<S>                           <C>                <C>
North America                    $      933          $    1,116
Europe                                  141                 160
Pacific Rim                               2                   2
                                 ----------          ----------
Total                            $    1,076          $    1,278
                                 ==========          ==========
</Table>

Additional information regarding revenue by product line is as follows: (in
thousands)

<Table>
<Caption>
                                  Three months ended March 31,
Revenue                             2002                2001
-------                          ----------          ----------
<S>                              <C>                 <C>
Broadband Telecom                $    2,159          $    2,559
Combo                                 2,628               1,126
LAN                                     796               2,963
Storage                                 438               2,469
WAN                                      88                 340
Other                                   191                 494
                                 ----------          ----------
Total                            $    6,300          $    9,951
                                 ==========          ==========
</Table>

6.  RECENTLY ISSUED ACCOUNTING PRONOUNCEMENTS

In June 2001, the Financial Accounting Standards Board issued Statement of
Financial Accounting Standards ("SFAS") No. 141, "Business Combinations," and
SFAS No. 142, "Goodwill and Other Intangible Assets." The most significant
changes made by SFAS No. 141 are: 1) requiring that the purchase method of
accounting be used for all business combinations initiated after June 30, 2001;
and 2) establishing specific criteria for the recognition of intangible assets
separately from goodwill. SFAS No. 142 primarily addresses the accounting for
acquired goodwill and intangible assets. The provisions of SFAS No. 142 are
effective for fiscal years beginning after December 15, 2001. The most
significant changes made by SFAS No. 142 are: 1) goodwill and indefinite-lived
intangible assets are no longer amortized; 2) goodwill will be tested annually
and whenever events or circumstances occur indicating that goodwill might be
impaired; and 3) the amortization period of intangible assets with finite lives
will no longer be limited to forty years. The Company adopted SFAS No. 141
effective July 1, 2001, and SFAS No. 142 effective January 1, 2002, however, as
the Company's goodwill was determined to be impaired and was written off in the
fourth quarter of 2001, the adoption of these standards did not have a material
effect on the Company's financial position or results of operations for the
three months ended March 31, 2002.


                                       8
<PAGE>


The following tables show the impact that SFAS No. 142 would have had if adopted
as of January 1, 2001: (in thousands)

<Table>
<Caption>
                                                   Three months ended March 31,
                                                     2002                 2001
                                                  ----------           ----------
<S>                                               <C>                  <C>
Reported net loss                                 $     (566)          $     (188)
Goodwill amortization                                     --                   60
                                                  ----------           ----------
Adjusted net (loss) income                        $     (566)          $     (128)
                                                  ==========           ==========
</Table>

<Table>
<Caption>
                                                   Three months ended March 31,
Basic (loss) earnings per share:                     2002                 2001
                                                  ----------           ----------
<S>                                               <C>                  <C>
Reported net loss                                 $    (0.10)          $    (0.03)
Goodwill amortization                                     --                 0.01
                                                  ----------           ----------
Adjusted basic net (loss) earnings
per share                                         $    (0.10)          $    (0.02)
                                                  ==========           ==========
</Table>

<Table>
<Caption>
                                                   Three months ended March 31,
Diluted earnings per share:                          2002                 2001
                                                  ----------           ----------
<S>                                               <C>                  <C>
Reported net loss                                 $    (0.10)          $    (0.03)
Goodwill amortization                                     --                 0.01
                                                  ----------           ----------
Adjusted diluted net (loss) earnings
per share                                         $    (0.10)          $    (0.02)
                                                  ==========           ==========
</Table>

In August 2001, the FASB issued SFAS No. 144, "Accounting for the Impairment or
Disposal of Long-Lived Assets." SFAS No. 144 addresses financial accounting and
reporting for the impairment of long-lived assets and for long-lived assets to
be disposed of. This statement supersedes SFAS No. 121, "Accounting for the
Impairment of Long-Lived Assets and for Long-Lived Assets to Be Disposed Of;"
however, this statement retains the fundamental provisions of SFAS No. 121 for
(a) recognition and measurement of the impairment of long-lived assets to be
held and used, and (b) measurement of long-lived assets to be disposed of by
sale. This statement also supersedes the accounting and reporting provisions of
APB Opinion No. 30, "Reporting the Results of Operations -- Reporting the
Effects of Disposal of a Segment of a Business, and Extraordinary, Unusual and
Infrequently Occurring Events and Transactions" for segments of a business to be
disposed of. SFAS No. 144 is effective for fiscal years beginning after December
15, 2001. The Company adopted this standard effective January 1, 2002. The
adoption of this standard did not have a material effect on the Company's
financial position or results of operations as of and for the three months ended
March 31, 2002.



                                       9
<PAGE>




ITEM 2. MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS
        OF OPERATIONS

This report contains forward-looking statements about the business, financial
condition and prospects of the Company. These statements are made under the
"safe harbor" provisions of the Private Securities Litigation Reform Act of
1995. The actual results of the Company could differ materially from those
indicated by the forward-looking statements because of various risks and
uncertainties, including without limitation, changes in product demand, the
availability of products, changes in competition, economic conditions, various
inventory risks due to changes in market conditions and other risks indicated in
the Company's filings and reports with the Securities and Exchange Commission.
All the foregoing risks and uncertainties are beyond the ability of the Company
to control, and in many cases, the Company cannot predict the risks and
uncertainties that could cause its actual results to differ materially from
those indicated by the forward-looking statements. When used in this report, the
words "believes," "plans," "expects," "intent" and "anticipates" and similar
expressions as they relate to the Company or its management are intended to
identify forward-looking statements.

RESULTS OF OPERATIONS

Revenues consist of product and service revenues and are recognized in
accordance with SEC Staff Accounting Bulletin ("SAB") 101, "Revenue
Recognition." Product revenues are recognized upon shipment, provided fees are
fixed and determinable, a customer purchase order is obtained, and collection is
probable. Revenues from reseller agreements are recognized when the product is
sold through to the end customer unless an established return history supports
recognizing revenue upon shipment, less a provision for estimated sales returns.
The Company maintains its allowance for returns as a reduction to accounts
receivable. Deferred revenue consists of revenue from reseller arrangements and
certain arrangements with extended payment terms. Revenue from extended payment
terms is recognized in the period the payment becomes due if all other revenue
recognition criteria have been met. Service revenue is recognized as the
services are performed. The Company offers to its customers a limited warranty
that its products will be free from defect in the materials and workmanship for
a specified period. The Company has established a warranty reserve, as a
component of accrued liabilities, for any potential claims.

REVENUES: Total revenues for the three months ended March 31, 2002 were $6.3
million. Revenues for the same period in 2001 ("comparative period") were $10
million. The reduction in revenues is generally due to the continued market
slowdown, which has significantly reduced computer and communications equipment
purchasing by key customers, as well as the discontinuance of several lines of
legacy technologies. Legacy revenues decreased from $3.5 million for the three
months ended March 31, 2001 to $899,000 for the three months ended March 31,
2002. The decrease in legacy technology revenues was partially offset by revenue
growth in Combo technologies. Combo technologies revenues increased to $2.6
million in the first quarter 2002 from $1.1 million in the comparative period.



                                       10
<PAGE>

One customer individually accounted for 43% of the Company's first quarter 2002
revenue. In the comparative period, three customers individually accounted for
21%, 16%, and 10% of the Company's revenue.

GROSS MARGIN: Gross margin as a percentage of sales was 40% for the first
quarter 2002 and 51% for the comparative period. The gross margin rate for the
three month period declined approximately eight percentage points due to the
shift in product mix away from higher margin legacy and fibre channel products.
The remaining decline primarily related to the under-utilization of the
Company's manufacturing facility.

RESEARCH AND DEVELOPMENT: The Company's investment in the development of new
products through research and development was $1.6 million in the first quarter
2002 and $2.2 million in the comparative period. As a percentage of revenue,
research and development expenses were 26% in the first quarter 2002 and 22% in
the comparative period. Approximately 46% of the decrease in research and
development expenses for the three months ended March 31, 2002, was due to a
reduction in headcount associated with the Company's restructuring program and
other cost reduction initiatives implemented at the end of the second quarter
2001. The remaining portion of the decrease primarily related to decreased
spending on legacy sustaining engineering, partially offset by an increase in
telecommunications development spending. Research and development costs as a
percentage of sales increased due to the decrease in revenues.

SALES AND MARKETING: Sales and marketing expenses were $1.4 million in the first
quarter 2002 and $2.1 million in the comparative period. As a percentage of
revenue, sales and marketing expenses were 22% in the first quarter 2002 and 21%
in the comparative period. The decrease in sales and marketing expenses for the
three months ended March 31, 2002, was primarily due to a reduction in headcount
associated with the Company's restructuring program and other cost reduction
initiatives implemented at the end of the second quarter 2001. Sales and
marketing expenses were relatively flat as a percentage of sales.

GENERAL AND ADMINISTRATIVE: General and administrative expenses were $754,000 in
the first quarter 2002 and $1.1 million in the comparative period. As a
percentage of revenue, general and administrative expenses were 12% in the first
quarter 2002 and 11% in the comparative period. The decrease in general and
administrative expenses for the three months ended March 31, 2002, is primarily
the result of a reduction in headcount associated with the Company's
restructuring program and cost reduction initiatives implemented at the end of
the second quarter 2001. General and administrative expenses were relatively
flat as a percentage of sales.

INTEREST INCOME, NET: Interest income, net of interest expense, was $193,000 in
the first quarter 2002 and $83,000 in the comparative period. The increase
relates to higher daily cash levels available for investment and lower borrowing
interest rates.

OTHER INCOME (EXPENSE), NET: Other income (expense), net, was $56,000 in the
first quarter 2002 and ($37,000) in the comparative period. Other income
(expense), net in the comparative period includes the amortization of goodwill
and purchased intangibles. As the carrying value of the Company's goodwill and
purchased intangibles exceeded its fair value, the Company wrote off the
carrying amount of its goodwill in the fourth quarter of 2001 and


                                       11
<PAGE>

its purchased intangibles in the second quarter of 2001. Accordingly, the
increase in other income is primarily due to the elimination of amortization
expense related to these items.

INCOME TAXES: The Company's effective income tax rate was (45%) for the first
quarter 2002 and (25%) for the comparative period. The effective rate for the
first quarter 2002 differed from the statutory rate due to foreign income, which
is offset by foreign loss carryforwards. The effective rate for the first
quarter 2001 included the impact of nondeductible goodwill and purchased
intangibles amortization.

NET LOSS: The Company reported a net loss of $566,000 in the first quarter 2002
and a net loss of $188,000 in the comparative period.

LIQUIDITY AND CAPITAL RESOURCES

As of March 31, 2001, cash and cash equivalents totaled $10.6 million, an
increase of $191,000 from the December 31, 2001 balance of $10.4 million. The
increase was attributable to cash provided by operating activities of $613,000,
partially offset by cash used by investing activities of $160,000 and cash used
by financing activities of $262,000. Cash provided by operating activities was
due to a decrease in inventories of $1.2 million, a decrease in deferred income
taxes of $528,000, depreciation and amortization of $230,000, and a decrease in
accounts receivable of $433,000, which was partially offset by an increase in
income taxes receivable of $1.1 million and cash used to fund operations of
$566,000. Cash used by investing activities was primarily the result of
purchases of marketable securities of $385,000 and fixed asset additions of
$79,000, partially offset by proceeds from the sale of marketable securities of
304,000. Cash used by financing activities was primarily comprised of the
purchase of redeemable common stock of $254,000.

At March 31, 2002, the Company had no material commitments to purchase capital
assets. The Company's significant long-term obligations are its operating leases
on its facilities, future debt payments and repurchase of Interphase common
stock from Motorola, Inc. (described below). The Company has not paid any
dividends since its inception and does not anticipate paying any dividends in
2002.

In October 2001, the Company announced that its Board of Directors had
authorized the repurchase of up to $5 million of its common stock. Purchases are
authorized to be made from time to time during a twenty-four month period in the
open market or in privately negotiated transactions depending on market
conditions. The Company will cancel all shares that it repurchases. The
repurchase plan does not obligate the Company to repurchase any specific number
of shares and may be suspended at any time. The Company repurchased and
cancelled shares with a market value of approximately $8,000 during the three
months ended March 31, 2002.

The Company has a $5 million revolving credit facility with a financial
institution. The revolving credit facility expires in June 2003. As of March 31,
2002, the Company had borrowings of $3.5 million classified as long-term debt on
its balance sheet. These borrowings are fully collateralized by a certificate of
deposit.


                                       12
<PAGE>


Effective October 1998, the Company approved a stock repurchase agreement with
Motorola, Inc. to purchase ratably from October 1998 to July 2002, all of the
shares owned by Motorola for $4.1 million at $6.25 per share. Under the terms of
the agreement, Motorola retains the right as an equity owner and has assigned
its voting rights to the Company. The Company cancels the stock upon each
repurchase. Prior to the repurchase agreement, Motorola owned approximately 12%
of the Company's outstanding common stock. The future scheduled payments are
classified as redeemable common stock in the accompanying consolidated balance
sheets. As of March 31, 2002, 578,671 shares have been repurchased for $3.6
million and retired and 81,329 shares remain to be repurchased.

The Company expects that its cash, cash equivalents, marketable securities and
proceeds from its credit facility will be adequate to meet foreseeable cash
needs for the next twelve months. However, it is possible that the Company may
require additional sources of financing earlier than anticipated, as a result of
unexpected cash needs or opportunities, an expanded growth strategy or
disappointing operating results. Additional funds may not be available on
satisfactory terms when needed, whether within the next twelve to eighteen
months or thereafter.



                                       13
<PAGE>

                                     PART II

OTHER INFORMATION

ITEM 4. SUBMISSION OF MATTERS TO A VOTE OF SECURITY HOLDERS

On May 1, 2002, the annual meeting of shareholders of the Company was held. The
following matters were voted upon and approved at the meeting:

An election of directors of the Company to serve until the next annual meeting
for the Company was held. The following eight individuals were elected as
Directors of the Company:

<Table>
<Caption>
     Nominee                           Votes Cast For             Votes Withheld
     -------                           --------------             --------------
<S>                                    <C>                         <C>
Paul N. Hug                               4,586,239                   396,102
Gregory B. Kalush                         4,586,239                   396,102
Randall D. Ledford                        4,586,239                   396,102
Michael J. Myers                          4,586,239                   396,102
David H. Segrest                          4,586,239                   396,102
Kenneth V. Spenser                        4,586,239                   396,102
S. Thomas Thawley                         4,586,239                   396,102
William R. Voss                           4,586,239                   396,102
</Table>

An amendment to the Company's Amended and Restated Stock Option Plan to increase
the aggregate number of shares issuable upon exercise of options thereunder from
3,500,000 to 4,500,000 was ratified and approved:

<Table>
<Caption>
         For             Against           Abstain         Not Voted
      ---------          -------           -------         ---------
<S>                      <C>               <C>             <C>
      1,178,381          828,856           311,565         2,663,539
</Table>


ITEM 6.  REPORTS ON FORM 8-K

         None

         EXHIBITS

         None



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<PAGE>



SIGNATURE

Pursuant to the requirements 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
                                       (Registrant)
Date:  May 15, 2002

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




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