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                                                                    EXHIBIT 10.1

                                  For Bank Use Only       Reviewed by __________

                                  Due MARCH 31, 2006

                                  Customer # 7349736911   Loan # 166

                      AMENDMENT TO LOAN AGREEMENT AND NOTE

      This amendment (the "AMENDMENT"), dated as of the date specified below, is
by and between the borrower (the "BORROWER") and the bank (the "BANK")
identified below.

                                    RECITALS

      A. The Borrower and the Bank have executed a Loan Agreement (the
"AGREEMENT") dated MARCH 19, 2002 and the Borrower has executed a Note (the
"NOTE"), dated MARCH 19, 2002, either or both which may have been amended and
replaced from time to time, and the Borrower (and if applicable, certain third
parties) have executed the collateral documents which may or may not be
identified in the Agreement and certain other related documents (collectively
the "LOAN DOCUMENTS"), setting forth the terms and conditions upon which the
Borrower may obtain loans from the Bank from time to time in the original amount
of $ 10,000,000.00, as may be amended from time to time.

      B. The Borrower has requested that the Bank permit certain modifications
to the Agreement and Note as described below.

      C. The Bank has agreed to such modifications, but only upon the terms and
conditions outlined in this Amendment.

                               TERMS OF AGREEMENT

      In consideration of the mutual covenants contained herein, and for other
good and valuable consideration, the Borrower and the Bank agree as follows:

      [x] CHANGE IN MATURITY DATE. If checked here, any references in the
Agreement or Note to the maturity date or date of final payment are hereby
deleted and replaced with " MARCH 31, 2006".

      [ ] CHANGE IN MAXIMUM LOAN AMOUNT. If checked here, all references in the
Agreement and in the Note (whether or not numerically) to the maximum loan
amount are hereby deleted and replaced with "$_____________________", which
evidences an additional $________________________________ available to be
advanced subject to the terms and conditions of the Agreement and Note.

      [ ] TEMPORARY INCREASE IN MAXIMUM LOAN AMOUNT. If checked here,
notwithstanding the maximum principal amount that may be borrowed from time to
time under the Agreement and Note, the maximum principal amount that may be
borrowed thereunder shall increase from $ __________________________ to $
______________________ effective _______________ through ____________ annually.
On___________________________ through ___________________________ annually, the
maximum principal amount that may be borrowed thereunder shall revert to
$_______________________ and any loans outstanding in excess of that amount will
be immediately due and payable without further demand by the Bank.

      [ ] CHANGE IN MULTIPLE ADVANCE TERMINATION DATE. If checked here, all
references in the Agreement and in the Note to the termination date for multiple
advances are hereby deleted and replaced with" ________________________ ".

      CHANGE IN FINANCIAL COVENANT(s).

         (i)   [ ] If checked here, all references to "$ ___________ " in the
         Agreement as the minimum Net Working Capital amount are hereby deleted
         and replaced with "$ _________________ " for the period beginning
         _________________ and thereafter.

         (ii)  [ ] If checked here, all references to "$ _____________ " in the
         Agreement as the minimum Tangible Net Worth amount are hereby deleted
         and replaced with "$ _________________ " for the period beginning
         ______________________ and thereafter.

         (iii) [ ] If checked here, all references to " ________ " in the
         Agreement as the maximum Debt to Worth Ratio are hereby deleted and
         replaced with " _________________ " for the period beginning
         ____________________ and thereafter.

         (iv)  [ ] If checked here, all references to " ___________ " in the
         Agreement as the minimum Current Ratio are hereby deleted and replaced
         with " __________________ " for the period beginning ________________
         and thereafter.

         (v)   [ ] If checked here, all references to "$ ___________ " in the
         Agreement as the maximum Capital Expenditures amount are hereby deleted
         and replaced with "$ ____________________________ " for the period
         beginning _______ and thereafter.

         (vi)  [ ] If checked here, all references to " ___________ " in the
         Agreement as the minimum Cash Flow Coverage Ratio are hereby deleted
         and replaced with "$_________ " for the period beginning __________ and
         thereafter.

         (vii) [ ] If checked here, all references to "$ __________ " in the
         Agreement as the maximum Officers, Directors, Partners, and Management
         Salaries and Other Compensation amount are hereby deleted and replaced
         with "$ _______________ " for the period beginning _______________ and
         thereafter.

      [ ] CHANGE IN PAYMENT SCHEDULE. If checked here, effective upon the date
          of this Amendment, any payment terms are amended as follows:

                                  Page 1 of 3

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      [ ] CHANGE IN LATE PAYMENT FEE. If checked here, subject to applicable
law, if any payment is not made on or before its due date, the Bank may collect
a delinquency charge of _______% of the unpaid amount. Collection of the late
payment fee shall not be deemed to be a waiver of the Bank's right to declare a
default hereunder.

      [ ] CHANGE IN CLOSING FEE. If checked here and subject to applicable law,
the Borrower will pay the Bank a closing fee of $ _________ (apart from any
prior closing fee) contemporaneously with the execution of this Amendment. This
fee is in addition to all other fees, expenses and other amounts due hereunder.

      [ ] CHANGE IN BORROWING BASE. If checked here, the Borrowing Base is
hereby changed to an amount equal to the sum of (i) ________% of the face amount
of Eligible Accounts, and (ii) the lesser of $ ________________ or
____________________% of the Borrower's cost of Eligible Inventory, as such cost
may be diminished as a result of any event causing loss or depreciation in value
of Eligible Inventory less (iii) the current outstanding loan balance on note(s)
in the original amount(s) of $ ___________________________, and less (iv)
undrawn amounts of outstanding letters of credit issued by Bank or any affiliate
thereof. The Borrower will provide the Bank with information regarding the
Borrowing Base in such form and at such times as the Bank may request. The terms
used in this section will have the meanings set forth in a supplement entitled
"Financial Definitions," a copy of which the Borrower acknowledges having
received with this Amendment, which is incorporated herein by reference and
which replaces any prior Financial Definitions supplement.

      [ ] CHANGE IN PAID-IN-FULL PERIOD. If checked here, all revolving loans
under the Agreement and the Note must be paid in full for a period of at least
_________ consecutive days during each fiscal year. Any previous Paid-in-Full
provision is hereby replaced with this provision.

      DEFAULT INTEREST RATE. Notwithstanding any provision of this Note to the
contrary, upon any default or at any time during the continuation thereof
(including failure to pay upon maturity), the Bank may, at its option and
subject to applicable law, increase the interest rate on this Note to a rate of
5% per annum plus the interest rate otherwise payable hereunder. Notwithstanding
the foregoing and subject to applicable law, upon the occurrence of a default of
the Borrower or any guarantor involving bankruptcy, insolvency, receivership
proceedings or an assignment for the benefit of creditors, the interest rate on
this Note shall automatically increase to a rate of 5% per annum plus the rate
otherwise payable hereunder.

      EFFECTIVENESS OF PRIOR DOCUMENTS. Except as specifically amended hereby,
the Agreement, the Note and the other Loan Documents shall remain in full force
and effect in accordance with their respective terms. All warranties and
representations contained in the Agreement and the other Loan Documents are
hereby reconfirmed as of the date hereof. All collateral previously provided to
secure the Agreement and/or Note continues as security, and all guaranties
guaranteeing obligations under the Loan Documents remain in full force and
effect. This is an amendment, not a novation.

      PRECONDITIONS TO EFFECTIVENESS. This Amendment shall only become effective
upon execution by the Borrower and the Bank, and approval by any other third
party required by the Bank.

      NO WAIVER OF DEFAULTS; WARRANTIES. This Amendment shall not be construed
as or be deemed to be a waiver by the Bank of existing defaults by the Borrower,
whether known or undiscovered. All agreements, representations and warranties
made herein shall survive the execution of this Amendment.

      COUNTERPARTS. This Amendment may be signed in any number of counterparts,
each of which shall be considered an original, but when taken together shall
constitute one document.

      AUTHORIZATION. The Borrower represents and warrants that the execution,
delivery and performance of this Amendment and the documents referenced herein
are within the authority of the Borrower and have been duly authorized by all
necessary action.

      TRANSFERABLE RECORD. The agreement and note, as amended, is a
"transferable record" as defined in applicable law relating to electronic
transactions. Therefore, the holder of the agreement and note, as amended, may,
on behalf of Borrower, create a microfilm or optical disk or other electronic
image of the agreement and note, as amended, that is an authoritative copy as
defined in such law. The holder of the agreement and note, as amended, may store
the authoritative copy of such agreement and note, as amended, in its electronic
form and then destroy the paper original as part of the holder's normal business
practices. The holder, on its own behalf, may control and transfer such
authoritative copy as permitted by such law.

      ATTACHMENTS. ALL DOCUMENTS ATTACHED HERETO, INCLUDING ANY APPENDICES,
SCHEDULES, RIDERS, AND EXHIBITS TO THIS AMENDMENT, ARE HEREBY EXPRESSLY
INCORPORATED HEREIN BY REFERENCE.

                           [SIGNATURE(S) ON NEXT PAGE]

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Dated as of: MARCH  23, 2005

                                   RADISYS CORPORATION
(Individual Borrower)              Borrower Name (Organization)

___________________________        a OREGON Corporation

Borrower Name N/A                  By: /s/ Brian Bronson
                                       -----------------------------------------
                                   Name and Title: BRIAN BRONSON CAO & TREASURER

___________________________        By : _______________________________________

Borrower Name N/A                  Name and Title: ____________________________

Agreed to:

U.S. BANK N.A.
(Bank)

By: /s/ Le  Phan                   FOR ADDITIONAL TERMS,
    ------------                   SEE ATTACHED ADDENDUM
        LE  PHAN
Name and Title: VICE PRESIDENT

                                  Page 3 of 3

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                ADDENDUM TO AMENDMENT TO LOAN AGREEMENT AND NOTE

      This Addendum is made part of the Amendment to Loan Agreement and Note
(the "Amendment") made and entered into by and between the undersigned borrower
(the "Borrower") and the undersigned bank (the "Bank") as of the date identified
below, The following provisions are hereby added to the Amendment (or to the
extent such provisions already exist, are hereby modified) as follows.

LOAN TO VALUE. In addition to any other payments required on the Note, (a) the
par value of Eligible Collateral shall at all times be at least $ 25,000,000;
and if the par value is less than such amount, Borrower shall, within five days
after Bank gives written notice thereof to Borrower, grant to Bank a perfected
first priority security interest in additional Eligible Collateral in the amount
of such deficiency; and (b) if the maximum Loan Amount at any time exceeds 90%
of the fair market value, as determined by Bank, of the Eligible Collateral,
Borrower shall, within five days after Bank gives written notice thereof to
Borrower, grant to Bank a perfected first priority security interest in
additional Eligible Collateral sufficient to cause the maximum Loan Amount to be
not more than 80% of the fair market value of Eligible Collateral.

"Eligible Collateral" shall mean A1/P1 commercial paper or other securities
owned by the Borrower and acceptable to Bank in its sole discretion which are
held by the Borrower in Safekeeping Account No. 777127706 maintained with Bank,
in which the Bank has a perfected, first priority security interest; and which
are subject to no liens, encumbrances or security interest of any other person
or entity.

LOAN FEE. Notwithstanding any contrary provisions of the Agreement or Note,
Borrower shall pay the following loan fees to Bank for the period of time from
April 1, 2005 through March 31, 2006: (a) upon execution of the Amendment to
Loan Agreement and Note dated as of March 23, 2005, a loan fee of $ 2,000,00;
and (b) on the date of the first advance on the Note on or after April 1,2005, a
draw down fee equal to $ 50,000.00 (.25% of the Loan Amount) The foregoing fees
do not affect the fees payable by Borrower for any time period prior to April 1,
2005, which fees remain in effect for such time periods.

Dated as of March 23, 2005.

BORROWER:

RADISYS CORPORATION, an Oregon corporation

By: /s/ Brian Bronson
    --------------------------
Title: CAO & TREASURER 3/30/05

Agreed to:

BANK:

U.S. BANK N.A.

By: /s/ Le Phan
    -----------------------
    Le Phan, Vice President