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                                                                   EXHIBIT 10.13
                                PROMISSORY NOTE

                                   May 4, 1998

1.      General Automation, Inc. currently owes NCR Corporation ("NCR"), a
        Maryland corporation, the principal of $1,723,921.92. For Value
        received, General Automation, Inc. promises to make payments to NCR as
        set out in this Promissory Note as follows:

2.      The payment of the above principal, together with interest at the rate
        of 18% per annum shall be paid in a combination of eighteen (18)
        consecutive monthly payments of $86,065.25 each and one (1) balloon
        payment of $490,329.86. The first payment shall be due on May 1, 1998
        with the remaining payments due on the first of each month thereafter.

3.      General Automation and NCR agree that the principal amount in Paragraph
        1, subject to future reconciliation, will be adjusted up or down to the
        agreed upon amount at that time, with an appropriate adjustment to the
        monthly payment in Paragraph 2, Amortization will still occur over 24
        months, with a balloon payment due in 18 months.

4.      PAYMENT SHALL BE SENT VIA WIRE TRANSFER USING THE FOLLOWING INFORMATION
        PRIOR TO THE 1ST OF THE MONTH:

            BANK NAME               WACHOVIA BANK OF NORTH CAROLINA
            BANK ADDRESS            10301 DAVID TAYLOR DRIVE
                                    CHARLOTTE, NC2  28262
            ABA                     053100494
            BNF ACCT.               NCR CORPORATION
            BNF ACCT. NO            8739069518
            REFERENCE               RFBLB65245

        If General Automation fails to pay any monthly installment required to
        be paid under this Promissory Note when the installment is due, all
        unpaid installments shall, at NCR's option, become immediately due and
        payable; and in addition to such right of acceleration, NCR shall be
        entitled to any and all remedies available under the law or equity,
        including collection charges of 1.5% per month and attorney fees.
        Subject to the late fees, General Automation shall have five (5) in
        which to cure any defaults under this note.

5.      General Automation hereby waives presentment, demand for payment or
        notice of dishonor of this note, notice of protest, and protest and all
        other notices or demands in connection with the delivery, acceptance,
        performance, default, endorsement or guaranty of this instrument.

6.      General Automation shall have the right to prepay all or part of the
        outstanding principal balance under this note without penalty and
        without credit for interest paid or previously due.

7.      No act or failure to act or verbal statement can waive or alter any term
        or condition of this Promissory Note. This Promissory note shall
        constitute the sole agreement in regard to the above-said principal sum
        and shall supersede all prior agreements and understandings, whether
        oral or written. This Promissory Note may not be altered, and/or any
        provision or right waived, except in a signed writing. Any provision
        voided by law shall be severable and not impair any remaining provision.

8.      This note cannot be assigned by General Automation with the written
        consent of NCR. Any attempt to assign or otherwise transfer the
        obligation of General Automation without consent shall make this notice
        due and immediately payable in full.


NCR Corporation                            General Automation, Inc.


----------------------------               -----------------------------
By Sandra A. Martinez                      By Richard Nance
Manager, Credit &                          CFO, General Automation
Third Party Collections, NCR               5/4/98
Date: 5/4/98