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                                                                    Exhibit 10.2


                                 PROMISSORY NOTE


$4,667,573                                                        April 14, 2000


         Paradyne Corporation ("Paradyne"), FOR VALUE RECEIVED, hereby promises
to pay to the order of Control Resources Corporation, a Delaware corporation
("CRC"), on September 15, 2000 (or sooner, as herein provided) at the offices of
P-COM, Inc., 3175 S. Winchester Blvd., Campbell, CA 95008 or at such location as
the holder hereof may hereafter designate in writing, the principal sum of
US$4,667,573, as such amount may be adjusted as provided for in Section 1 below
(the "Principal Sum"). The Principal Sum from time to time outstanding shall
bear interest payable at a rate equal to the Prime Rate of US commercial banks
as published in the Wall Street Journal (Eastern edition) from time to time (or
if more than one such rate is published, the average of such rates).

         Paradyne has on the date hereof purchased certain of the assets of CRC
pursuant to the terms and conditions of the Asset Purchase Agreement, dated
April 5, 2000 by and between Paradyne, Paradyne Networks, Inc., P-COM, Inc. and
CRC (the "Purchase Agreement"). Capitalized words and phrases used and not
otherwise defined in this Note have the meanings provided in the Purchase
Agreement. Paradyne hereby covenants and agrees with CRC as follows:

         1. The Principal Sum shall be increased or decreased, as the case may
be, as provided for in the Purchase Agreement.

         2. Paradyne may prepay, in whole or in part, the Principal Sum in cash
by wire transfer of immediately available funds to CRC's account in an amount
equal to the full




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amount due, without penalty or premium, at any time prior to September 15, 2000
on the condition that together with any such prepayment Paradyne shall pay all
accrued but unpaid interest on the amount being prepaid.

         3. On September 15, 2000 Paradyne may pay the Principal Sum and any
interest payable thereon by (a) the issuance to CRC of registered shares of
common stock of Paradyne Networks, Inc. with the number of such shares based on
the average closing price of Paradyne Networks, Inc.'s common stock on the 7
business days immediately preceding the day such shares of common stock of
Paradyne Networks, Inc. are delivered to CRC, and (b) delivery of a good check
to CRC for the difference between the total value of such shares and the full
amount due under this Note.

         4. If any payments of principal or interest hereunder become due and
payable on a Saturday, Sunday or public holiday under the laws of the State of
Delaware, the due date of such payment shall be extended to the next succeeding
full business day and, in the case of principal, interest thereon shall be
payable at the applicable rate during such extension.

         5. This Promissory Note may not be changed or discharged orally, but
only by an agreement in writing and signed by the party against whom enforcement
of any waiver, change, modification or discharge is sought.

         6. Presentment or demand for payment, notice of dishonor, protest and
notice of protest are hereby waived.

         7. This Promissory Note shall be governed by, and construed in
accordance with, the laws of the State of Delaware without reference to choice
of law doctrine.




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         IN WITNESS WHEREOF, this Promissory Note is executed and delivered on
the date first above written.



                                            PARADYNE CORPORATION

                                            By: /s/ James L. Slattery
                                                -----------------------------
                                                James L. Slattery
                                                Senior Vice President



















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