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                                 Exhibit 10(t)

                                                                   April 3, 1984

Amdahl Corporation
1250 East Arques
Sunnyvale, CA 94086
U.S.A.

Attention:     Mr. John C. Lewis
               President


Gentlemen:

This letter will confirm the agreements and representations of Fujitsu Limited
("Fujitsu") and Amdahl Corporation ("Amdahl") with respect to the acquisition by
Fujitsu of 6,007,832 shares (the "Shares") of Amdahl Common Stock, $.05 par
value ("Common Stock") and warrants to purchase 2,490,000 shares of Common Stock
expiring December 31, 1984 ("Warrants") from Heizer Corporation ("Heizer").  For
purposes of this Agreement, the term "Amdahl Equity Securities" at a particular
time shall mean all shares of Amdahl Common Stock, $.05 par value, Amdahl
Preferred Stock and any other class or series of equity securities then
authorized in the Amdahl Certificate of Incorporation, and all such securities
issuable upon conversion or exercise of any then outstanding options, warrants
or convertible securities of Amdahl.

1.  Neither Fujitsu nor any majority-owned subsidiary of Fujitsu (collectively
    called "Fujitsu Group") will, without the prior approval of Amdahl, directly
    or indirectly, acquire any Amdahl Equity Securities, whether in the open
    market, directly from Amdahl, directly from other Amdahl security holders,
    or otherwise, if such acquisition would result in the Fujitsu Group's
    Percentage Ownership of Common Stock Outstanding On A Fully Diluted Basis
    exceeding 49.5% of all Common Stock Outstanding On A Fully Diluted Basis.
    "Common Stock Outstanding On A Fully Diluted Basis" shall mean all shares of
    Common Stock having voting power in the election of directors outstanding at
    any time plus all shares of Common Stock issuable upon conversion or
    exercise of securities convertible into, and rights to acquire, Common Stock
    having voting power in the election of directors outstanding at any time.

2.  Section 1 (a) (i) of the Amdahl/Fujitsu 1982 Agreement, dated as of March 4,
    1982, is hereby amended so as to delete the number "31.3%" wherever it
    appears and to substitute therefor the number "49.5%".

3.  The provisions of this Agreement will become effective on the date of the
    closing of the purchase of the Shares and Warrants by Fujitsu from Heizer
    and shall remain in full

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    force and effect until the tenth anniversary of such date, or earlier
    termination as provided below, after which such provisions, except for
    provisions of Section 2 above, which shall survive, shall become null and
    void and will cease to have any further force or effect, provided, however,
    that this Agreement (except for Section 2) may be terminated by Fujitsu or
    by Amdahl by delivering a written notice of termination to the other party
    at any time during the period from April 1, 1990 to June 30, 1990.
 
4.  Each party hereto acknowledges that the breach of any of its agreements
    contained herein would result in irreparable damage to the other which could
    not be adequately compensated in monetary damages.
 
5.  This Agreement shall be governed by and construed in accordance with the 
    laws of the State of Delaware.

If the foregoing correctly sets forth the understanding between us, please
execute this letter in the space provided below, whereupon it will become a
binding agreement between us pursuant to its terms.

                                        Very truly yours,

                                        FUJITSU LIMITED


                                        By    TAKUMA YAMAMOTO
                                              -----------------
                                              (Takuma Yamamoto)
                                              President


Acknowledge and agreed to:

AMDAHL CORPORATION


By   JOHN C. LEWIS
     ---------------
     (John C. Lewis)

