<PAGE>   1
                                                                                
                                                                  EXHIBIT 10.29

                                 DENNIS C. HAYES
                               110 BELLACREE ROAD
                             DULUTH, GEORGIA U.S.A.

                                 April 12, 1996

                                  CONFIDENTIAL

Hayes Microcomputer Products, Inc.
5835 Peachtree Corners East
Norcross, Georgia  30092

Rinzai Limited
c/o Acma Limited
17 Jurong Port Road
Singapore  619092

And the Investors Shown on Schedule 1 hereto

                          RE: INDEMNIFICATION AGREEMENT

Dear Sirs:

                  This letter will set forth my personal binding obligation and
agreement ("Agreement") to provide indemnification to Rinzai Limited ("Rinzai")
and the other Investors under that certain Agreement and Plan of Merger dated
April 12, 1996 (the "Agreement"), related to any actions, suits, proceedings,
claims or demands of Gary J. Franza, John Stuckey and Mikhail Drabkin ("Employee
Actions") as set forth below.

                  1.       I acknowledge that Hayes Microcomputer Products, Inc.
                           ("Hayes") has undertaken to indemnify the Investors
                           against Employee Actions as provided in Section
                           7.1(d) of the Agreement. It is my intention by virtue
                           of this Agreement to provide further indemnification
                           to the Investors for Employee Actions as stated
                           below.

                  2.       In the event that the Employee Actions as finally
                           adjudicated pursuant to a nonappealable order results
                           in an aggregate liability to the Company, or if the
                           Employee Actions are settled for an amount, in excess
                           of $2,000,000 (the "Excess Amount"), then I hereby
                           agree to indemnify the Investors for such Excess
                           Amount in the following manner. I will transfer to
                           each of the Investors a number of shares of my stock
                           in Hayes equal in value to each Investor's
                           proportional share (based on their relative


<PAGE>   2


Hayes Microcomputer Products, Inc.
Rinzai Limited
April 12, 1996
Page 2

                           shareholdings in Hayes) of the Excess Amount. The
                           number of shares of stock shall be determined by
                           dividing the Excess Amount by the value per share of
                           the Hayes stock at the time of final adjudication of
                           liability or settlement of the Employee Actions. The
                           value per share of Hayes stock shall be determined as
                           follows:

                           (i)      If the Company has completed an initial
                                    public offering ("IPO") and its stock is
                                    publicly traded, the value per share shall
                                    be deemed to be the average closing price
                                    per share for each of the twenty (20) days
                                    prior to the final adjudication of liability
                                    or settlement, on NASDAQ/NMS or other
                                    exchange where Hayes shares are traded; or

                           (ii)     If Hayes has not completed an IPO at the
                                    time of the final adjudication of liability
                                    or settlement, then the value per share of
                                    Hayes stock shall be (i) for a period of six
                                    (6) months from the date of the Closing
                                    under the Agreement, US$7.14 and (ii)
                                    thereafter the total value of Hayes divided
                                    by the total number of issued and
                                    outstanding shares (on a fully diluted basis
                                    taking into account any then-exercisable
                                    options and warrants). The total value of
                                    Hayes shall be determined by the average of
                                    two (2) reputable nationally recognized
                                    appraisers, one selected by Rinzai and one
                                    selected by Dennis C. Hayes. The two
                                    appraisers' determinations shall be made in
                                    accordance with appropriate procedures and
                                    protocols to be established by Rinzai and
                                    Dennis C. Hayes at the time. For example,
                                    Rinzai and Dennis C. Hayes may instruct the
                                    appraisers to give full market value to the
                                    intellectual property estate and patent
                                    estate of Hayes for purposes of performing
                                    their valuation of Hayes. The appraisers
                                    shall complete their valuation within thirty
                                    (30) days after the date of appointment of
                                    both appraisers and the arithmetic average
                                    of the two valuations determined by the two
                                    appraisers shall be final, binding and
                                    conclusive on the parties.

                           The total value as established in (ii) above shall be
                           divided by the total issued and outstanding shares
                           (on a fully diluted basis taking into account any
                           then-exercisable options and warrants) of Hayes to
                           arrive at the value per share. The Excess Amount
                           shall then be divided by the value per share of the
                           Hayes stock determined by either paragraph 2(i) or
                           (ii) above, 

<PAGE>   3
Hayes Microcomputer Products, Inc.
Rinzai Limited
April 12, 1996
Page 3

                           and the resulting number of shares shall be
                           distributed to the Investors in proportion to their
                           shareholdings as a percentage of all issued and
                           outstanding shares of Hayes.

                  3.       In the event that any shares of stock in Hayes are
                           required to be transferred pursuant to any Employee
                           Action to any one of the Employees pursuant to a
                           final, nonappealable court order or settlement, then
                           I agree to transfer such shares to the Employees from
                           my own shares and neither the Company nor the
                           Investors shall have any responsibility for issuing
                           any new shares to the Employees.

                  It is understood that the Company will defend all Employee
Actions and will bear the cost of defense of such Employee Actions. It is my
further understanding that I, as Chairman of the Company in complete compliance
with my fiduciary duties as an officer of the Company (which fiduciary duties
shall not be altered or influenced in any way by my obligations under this
agreement), will be responsible for overall direction of the litigation of the
Employee Actions, although any settlement will be subject to approval of the
Board of Directors.

                  This letter constitutes my binding obligation to indemnify the
Investors as above stated. It is given for valuable consideration in the amount
of Ten Dollars ($10.00), as an inducement to the Investors to enter into the
Agreement and other good and valuable consideration and is given without any
undue influence or duress.

                                              Very truly yours,

                                              /s/ Dennis C. Hayes

                                              Dennis C. Hayes, Individually



<PAGE>   4


                                   Schedule 1

Kaifa Technology (H.K.) Limited

Lao Hotel (H.K.) Limited

S.P. Quek Investments Pte Ltd.

Saliendra Pte Ltd.

Rolling Profit Holdings, Limited