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                                                                   EXHIBIT 10.13


                       [Amphion Ventures L.P. Letterhead]



AXCESS Inc.                                                  September 30, 1999
3208 Commander Drive
Dallas, Texas 75006

         Re:      Series A, B and C Preferred Stock Dividends

Ladies and Gentlemen:

         Amphion Ventures L.P. ("Amphion"), hereby notifies and directs AXCESS
Inc. (the "Company") to pay all accrued, but unpaid dividends which are
outstanding as of the date of this letter for the six month period from April 1,
1999, to September 30, 1999 (approximately $190,000) on the shares of Series A,
B and C Convertible Preferred Stock of the Company held by Amphion as of the
date of this letter (collectively the "Accrued Dividends") in kind by issuing to
Amphion additional shares of Series A, B or C Preferred Stock, respectively, of
the Company. Further, Amphion hereby directs the Company to exchange the
additional shares of Series A, B and C Convertible Preferred Stock of the
Company for 19 shares of the Series J NonVoting Preferred Stock (the "Series J
Preferred Stock") of the Company.

         1. Payment of Accrued Dividends; Issuance of Shares. Amphion hereby
directs the Company to issue 19 shares of Series J Preferred Stock in exchange
for the shares of Series A, B and C Convertible Preferred Stock, respectively,
issued to Amphion as payment in full for the Accrued Dividends (the "Shares").
On and as of the date of this letter, the Accrued Dividends shall automatically
be converted and discharged in full and Amphion shall be the due and valid
holder of record of the Shares.

         2. Conversion of Non-Voting Common Stock to Voting Common Stock.
Amphion hereby agrees that it shall not, without the prior written consent of
the Company, convert any shares of the non-voting common stock of the Company
issuable to Amphion upon its conversion of any shares of Series J Preferred
Stock to voting common stock of the Company.

         3. Securities Act Legend; Registration Rights.

            3.1 The Shares will not be registered under the Securities Act of
1933, as amended (the "Securities Act"). Certificates representing the Shares
shall bear a restrictive legend substantially to the effect of the following:

         THE SECURITIES REPRESENTED HEREBY HAVE NOT BEEN REGISTERED UNDER THE
         SECURITIES ACT OF 1933, OR APPLICABLE STATE SECURITIES LAWS, OR THE
         SECURITIES LAWS OF ANY OTHER JURISDICTION. THEY MAY NOT BE SOLD OR
         TRANSFERRED IN THE ABSENCE OF AN EFFECTIVE REGISTRATION STATEMENT UNDER
         THOSE SECURITIES LAWS OR PURSUANT TO AN EXEMPTION THEREFROM. ADDITIONAL
         RESTRICTIONS REGARDING THE TERMS UNDER WHICH THE SHARES REPRESENTED BY
         THIS CERTIFICATE MAY BE CONVERTED INTO VOTING OR NON-VOTING COMMON
         STOCK OF THE



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AXCESS Inc.
September 30, 1999
Page 2



         COMPANY, AS THE CASE MAY BE, ARE SET FORTH IN THAT CERTAIN NOTE PAYABLE
         CONVERSION AGREEMENT EFFECTIVE AS OF DECEMBER 31, 1998.

         4. Representations and Warranties by the Company. The Company hereby
represents and warrants to Amphion as follows:

            4.1 The Company is a corporation duly organized, validly existing
and in good standing under the laws of the State of Delaware, and has the
corporate power and authority to execute and deliver this agreement, to issue
the Shares on the basis described herein and otherwise to perform its
obligations under this agreement.

            4.2 The execution and delivery by the Company of this Agreement, the
issuance of the Shares, and the performance by the Company of its obligations
hereunder, have been duly authorized by all requisite corporate action on the
part of the Company and will not (a) violate any provision of law, statute, rule
or regulation or any order of any court or other agency of government, (b)
conflict with or violate the Certificate of Incorporation or By-Laws of the
Company, in each case as amended, or (c) violate, conflict with or constitute
(with due notice or lapse of time or both) a default under any indenture,
mortgage, lease, license, agreement or other contract or instrument or result in
the creation or imposition of any lien, charge or encumbrance of any nature upon
the properties or assets of the Company or any of its subsidiaries, in each case
if such violation, conflict, default, lien, charge or encumbrance would have a
material adverse effect on the Company.

            4.3 This agreement has been duly executed and delivered by the
Company and constitutes the valid and legally binding obligation of the Company,
enforceable in accordance with its terms, except to the extent the
enforceability hereof may be limited by applicable bankruptcy, moratorium or
similar laws affecting the rights of creditors generally.

            4.4 Based in part upon the representations and warranties of Amphion
contained in this agreement, no registration or filing with, or consent or
approval of, or other action by, any federal, state or other governmental
department, commission, board, bureau, agency or instrumentality or any third
party is or will be necessary for the execution and delivery of this agreement
by the Company and the issuance of the Shares hereunder, other than the filing
of a notice of sale on Form D with the Securities and Exchange Commission in
accordance with the rules and regulations thereof under the Securities Act.

            4.5 The Shares are duly authorized, validly issued, fully paid and
non-assessable shares of Series J Preferred Stock and are not subject to any
preemptive rights.

            4.6 The Company shall cause to be delivered to Amphion a true copy
of the Series J Certificate of Designation, which was approved and adopted by
the Board of Directors of the Company.

         5. Representations and Warranties of Amphion. Amphion hereby represents
and warrants to the Company as follows:

            5.1 Amphion is acquiring the Shares for its own account, for
investment and not with a view to the distribution thereof within the meaning of
the Securities Act.




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AXCESS Inc.
September 30, 1999
Page 3

            5.2 Amphion understands that the Shares have not been registered
under the Securities Act, by reason of their issuance by the Company in
transactions exempt from the registration requirements of the Securities Act,
and that the Shares must be held by Amphion indefinitely unless a subsequent
disposition thereof is registered under the Securities Act or is exempt from
such registration.

            5.3 Amphion further understands that the exemption from registration
afforded by Rule 144 (the provisions of which are known to it) promulgated under
the Securities Act depends on the satisfaction of various conditions, and that,
if applicable, Rule 144 may afford the basis for sales only in limited amounts,
after compliance with the holding periods and other provisions thereof.

            5.4 Amphion understands that its investment hereunder involves
substantial risks and represents and warrants that it has made such independent
examinations and investigations of the Company as it has deemed necessary in
making its investment decision, and Amphion further represents and warrants that
it has had sufficient access to the officers, directors, books and records of
the Company as it has deemed necessary to conduct such examination and
investigation and make such investment decision.

            5.5 Amphion is able to bear the economic risk of the investment
contemplated by this agreement and has such knowledge and experience in
financial and business matters that it is capable of evaluating the merits and
risks of the investment contemplated by this agreement.

         6. Miscellaneous.

            6.1 This agreement constitutes our entire agreement with respect to
the subject matter hereof. This agreement may not be modified or amended or any
provision hereof waived except by an instrument in writing signed by the Company
and Amphion.

            6.2 This agreement shall be binding upon and inure to the benefit of
the parties hereto and their respective successors and permitted assigns. The
rights of Amphion hereunder shall be assignable to any holder of the Shares.
Except as provided in the immediately preceding sentence, this agreement and the
rights of Amphion hereunder shall not be assignable, and any purported
assignment hereof or thereof shall be void.

            6.3 This Agreement may be executed in any number of counterparts and
on separate counterparts, each of which shall be an original instrument, but all
of which together shall constitute a single agreement. One or more signature
pages from any counterpart of this Agreement may be attached to any other
counterpart of this Agreement without in any way changing the effect thereof.
This Agreement shall be effective when executed and delivered by the Company and
Amphion.

            6.4 All notices, requests, demands, consents, waivers, or other
communications made hereunder to any party or holder of Shares shall be in
writing and shall be deemed to have been duly given if delivered personally or
sent by nationally-recognized overnight courier, facsimile or by first class
registered or certified mail, return receipt requested, postage prepaid,
addressed to such party at the address set forth below:

            if to the Company, to the Company at its address
            first set forth above,:



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AXCESS Inc.
September 30, 1999
Page 4

            with a copy to:

            Sayles & Lidji, P.C.
            4400 Renaissance Tower
            1201 Elm Street
            Dallas, Texas 75270
            Attention: Michael R. Dorey, Esq.; and

            if to Amphion, to Amphion at its address
            first set forth above,

or to such other address as the party to whom such communication is to be given
may have furnished to the other party in writing in accordance herewith. All
such notices, requests, demands, consents, waivers or other communications shall
be deemed to have been delivered (a) in the case of personal delivery, on the
date of delivery, (b) if sent by facsimile, on the date sender receives a
confirmation confirming receipt, (c) if sent by overnight courier, on the next
business day following the date sent and (iv) in the case of mailing, on the
third business day following such mailing.

            6.5 All representations, warranties and agreements contained herein
shall survive the execution and delivery of this Agreement and the sale of the
Shares hereunder.

            6.6 This agreement, and all rights, obligations and liabilities
hereunder, shall be construed according to the laws of the State of New York
applicable to contracts made and to be performed wholly therein. Any judicial
proceeding brought against the Company to enforce, or otherwise in connection
with, this agreement may be brought in any court of competent jurisdiction in
the City of New York, and, by execution and delivery of this agreement, the
Company (i) accepts, generally and unconditionally, the nonexclusive
jurisdiction of such courts and any related appellate court and irrevocably
agrees to be bound by any final judgment rendered thereby in connection with
this agreement and (ii) irrevocably waives any objection it may now or hereafter
have as to the venue of any such proceeding brought in such a court or that such
a court is an inconvenient forum.

         If the foregoing correctly sets forth your understanding of our
agreement, please so indicate by signing and returning to the Company the
enclosed counterpart of this Agreement.

                                   Very truly yours,

                                   Amphion Ventures L.P.

                                   By: Amphion Partners L.L.C.,
                                         its General Partner



                                   By:
                                      ------------------------------------------
                                         Richard C.E. Morgan, Managing Member





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AXCESS Inc.
September 30, 1999
Page 5

The undersigned agrees with and accepts the foregoing terms and provisions as of
the date first above written

AXCESS INC.


By:
   ---------------------------------------------------------------
   James R. Craig, Chief Financial Officer and Secretary