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                                                                     EXHIBIT 2.1

                           SECOND AMENDED AND RESTATED
                            ARTICLES OF INCORPORATION
                                       OF
                                 MICRO-ASI, INC.


         Pursuant to the provisions of Articles 4.04 and 4.07 of the Texas
Business Corporation Act, Micro-ASI, Inc. (the "Corporation"), hereby adopts
these Second Amended and Restated Articles of Incorporation of the Corporation
("Restated Articles of Incorporation") which accurately copy the Articles of
Incorporation of the Corporation and all amendments thereto that are in effect
to date and as further amended by such Restated Articles of Incorporation, as
hereinafter set forth, and which contain no other change in any provision
thereof.

ARTICLE A. The Articles of Incorporation of the Corporation are amended by the
Restated Articles of Incorporation as follows:

         1. Article III of the Articles of Incorporation is hereby amended to
read in its entirety as follows:

                                  "ARTICLE III

         The corporation is authorized to issue ninety million (90,000,000)
         shares of capital stock. Seventy-five million (75,000,000) of the
         authorized shares shall be common stock, $0.001 par value per share
         ("Common Stock"), and fifteen million (15,000,000) of the authorized
         shares shall be preferred stock, $0.001 par value per share ("Preferred
         Stock")."

         2. Article IV of the Articles of Incorporation is hereby amended to
read in its entirety as follows:

                                   "ARTICLE IV

         Section A. Except as may otherwise be provided by the board of
         directors, no holder of any shares of stock of this corporation shall
         have any preemptive right to purchase, subscribe for, or otherwise
         acquire any shares of stock of the corporation of any class now or
         hereafter authorized, or any shares exchangeable for or convertible
         into such shares, or any warrants or other instruments evidencing
         rights or options to subscribe for, purchase or otherwise acquire such
         shares.

         In accord with Article 2.13 of the Texas Business Corporation Act and
         pursuant to Article IV of these Restated Articles of Incorporation,
         authority is expressly vested in the board of directors of the
         corporation to establish series of unissued shares of any class by
         fixing and determining the designations, preferences, limitations and
         relative rights, including voting rights, of the shares of any series
         so established to the same extent that such designations, preferences,
         limitations and relative rights could be stated if fully set forth in
         the Restated Articles of Incorporation.


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         In accord with Article 2.13(c) of the Texas Business Corporation Act
         and pursuant to Article IV of these Restated Articles of Incorporation,
         authority is expressly vested in the board of directors to eliminate
         from the Restated Articles of Incorporation any series of capital stock
         referenced therein, provided that no shares of capital stock were
         issued or because no issued shares of such series remain outstanding.
         To eliminate such series, the board of directors shall adopt a
         resolution to this effect and all eliminated shares shall resume the
         status of authorized but unissued shares of any eliminated class.

         Section B. The Common Stock shall consist of 75,000,000 shares, $0.001
         par value per share. Subject to the rights of holders of stock of the
         corporation senior to the Common Stock with respect to the declaration
         and payment of dividends, holders of Common Stock shall be entitled to
         receive such dividends and other distributions in cash, stock or
         property of the corporation as may be declared thereon by the board of
         directors from time to time out of assets or funds of the corporation
         legally available therefor. At every meeting of the shareholders of the
         corporation, every holder of Common Stock shall be entitled to one vote
         in person or by proxy for each share of Common Stock standing in his
         name on the transfer books of the corporation.

         Section C. The Preferred Stock shall consist of 15,000,000 shares,
         $0.001 par value per share.

                           1. The Preferred Stock may, from time to time, be
                  divided into and issued in one or more series, with each
                  series to be so designated as to distinguish the shares
                  thereof from the shares of all other series. The shares of
                  each series may have such powers, designations, preferences,
                  relative rights, qualifications, limitations or restrictions
                  as are stated herein and in one or more resolutions providing
                  for the issue of such series adopted by the board of directors
                  of the corporation as provided in this Section C.

                           2. To the extent that these Restated Articles of
                  Incorporation do not fix and determine the variations in the
                  relative rights and preferences of the Preferred Stock, both
                  in relation to the Common Stock and as between series of
                  Preferred Stock, the board of directors is expressly vested
                  with the authority to divide the Preferred Stock into one or
                  more series and, within the limitations set forth in these
                  Restated Articles of Incorporation, to fix and determine the
                  relative rights and preferences of the shares of any series so
                  established and, with respect to each such series, to fix by
                  one or more resolutions providing for the issue of such
                  series, the following:

                                    (a) The distinctive designation of, and the
                           number of shares of Preferred Stock which shall
                           constitute, the series, which number may be increased
                           or decreased (but not below the number of shares
                           thereof then outstanding) from time to time by action
                           of the board of directors.


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                                    (b) The dividend rate, if any, on the shares
                           of such series and the date or dates from which
                           dividends shall commence to accrue or accumulate, the
                           terms and conditions upon which dividends, if any, on
                           the shares of such series shall be paid, and whether
                           or in what circumstances such dividends shall be
                           cumulative.

                                    (c) The price at and the terms and
                           conditions on which the shares of such series may be
                           redeemed, including (without limitation) the time
                           during which shares of the series may be redeemed and
                           the premium, if any, over and above the par value
                           thereof that the holders of shares of such series
                           shall be entitled to receive upon the redemption
                           thereof, which premium may vary at different dates
                           and may also be different with respect to shares
                           redeemed through the operation of any retirement or
                           sinking fund.

                                    (d) The liquidation preference, if any, over
                           and above the par value thereof that the holders of
                           shares of such series shall be entitled to receive
                           upon the voluntary or involuntary liquidation,
                           dissolution or winding-up of the affairs of the
                           corporation.

                                    (e) Whether or not the shares of such series
                           shall be subject to the operation of a retirement or
                           sinking fund, and, if so, the extent and manner in
                           which any such retirement or sinking fund shall be
                           applied to the purchase or redemption of the shares
                           of such series for retirement or for other corporate
                           purposes, and the terms and provisions of such
                           retirement or sinking fund.

                                    (f) The terms and conditions, if any, on
                           which the shares of such series shall be convertible
                           into, or exchangeable for, shares of any other class
                           or classes of capital stock of the corporation or any
                           series of any other class or classes, or of any other
                           series of the same class, including (without
                           limitation) the price or prices or the rate or rates
                           of conversion or exchange and the method, if any, of
                           adjusting the same; provided, that shares of such
                           series may not be convertible into shares of a series
                           or class that has prior or superior rights and
                           preferences as to dividends or distribution of assets
                           of the corporation upon voluntary or involuntary
                           liquidation, dissolution or winding-up of the affairs
                           of the corporation.

                                    (g) The voting rights, if any, on the shares
                           of such series (in  addition to voting rights
                           provided by law).

                                    (h) Any or all other preferences and
                           relative, participating, optional or other special
                           rights, or qualifications, limitations or
                           restrictions thereof, as shall not be inconsistent
                           with the law or with this Article IV.

                           3. All shares of any one series of Preferred Stock
                  shall be identical with each other in all respects, except
                  that shares of any one series issued at different times


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                  may differ as to the dates from which dividends thereon, if
                  any, shall commence to accrue or accumulate; and all series
                  shall rank equally and be identical in all respects, except as
                  permitted by this Section C.

                           4. Except as provided in the resolution or
                  resolutions adopted by the board of directors providing for
                  the issue of the series of Preferred Stock, no vote or consent
                  of the holders of outstanding shares of that series shall be
                  required for the issue by the board of directors of any other
                  series of Preferred Stock, whether or not the rights and
                  preferences of any such other series shall be fixed by the
                  board of directors as senior to, or on a parity with, the
                  rights and preferences of that outstanding series."

         3.       The Articles of Incorporation as set forth in the Restated
Articles of Incorporation filed on February 14, 1997 are amended by deleting
Article I in its entirety and renumbering, together with internal references,
Article II as Article I, Article III (as amended above) as Article II, Article
IV (as amended above) as Article III, Article V as Article IV, Article VI as
Article V, Article VII as Article VI, Article VIII as Article VII, Article IX as
Article VIII and Article X as Article IX.

ARTICLE B. Each such amendment made by these Restated Articles of Incorporation
has been effected in conformity with the provisions of the Texas Business
Corporation Act and such Restated Articles of Incorporation, and each such
amendment made by these Restated Articles of Incorporation was duly adopted by
the shareholders of the Corporation on March 1, 2000.

ARTICLE C. The number of shares of capital stock of the Corporation outstanding
and entitled to vote at the time of the adoption of these Restated Articles of
Incorporation was 19,227,111 shares of common stock, $0.001 par value per share
(the "Common Stock").

ARTICLE D. The holders of 14,324,809 shares of Common Stock outstanding and
entitled to vote, which number exceeds two-thirds of the number of outstanding
shares of Common Stock, approved the adoption of these amendments. 78,400 shares
of Common Stock were voted against adoption of these amendments.

ARTICLE E. The Articles of Incorporation and all amendments and supplements
thereto that are in effect to date are hereby superseded by the following
Restated Articles of Incorporation which accurately copy the entire text thereof
and as amended as above set forth:

                                    ARTICLE I

Section A.  The name of the corporation is Micro-ASI, Inc.

Section B. The corporation's duration is perpetual, and it is organized to
engage in any and all lawful business for which corporations may be incorporated
under the Texas Business Corporation Act.


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Section C. The corporation will not commence business until it has received for
the issuance of its shares consideration of the value of $1,000, consisting of
money, labor done or property actually received.

Section D. The number of directors constituting the initial board of directors
is one, and the name and address of the person who is to serve as director until
the first annual meeting of the shareholders, or until his successor is elected
and qualified, is Cecil E. Smith, Jr. of 2350 Lakeside Boulevard, Suite 850,
Richardson, Texas 75082.

                                   ARTICLE II

The corporation is authorized to issue ninety million (90,000,000) shares of
capital stock. Seventy-five million (75,000,000) of the authorized shares shall
be common stock, $0.001 par value per share ("Common Stock"), and fifteen
million (15,000,000) of the authorized shares shall be preferred stock, $0.001
par value per share ("Preferred Stock").

                                   ARTICLE III

Section A. Except as may otherwise be provided by the board of directors, no
holder of any shares of stock of this corporation shall have any preemptive
right to purchase, subscribe for, or otherwise acquire any shares of stock of
the corporation of any class now or hereafter authorized, or any shares
exchangeable for or convertible into such shares, or any warrants or other
instruments evidencing rights or options to subscribe for, purchase or otherwise
acquire such shares.

In accord with Article 2.13 of the Texas Business Corporation Act and pursuant
to Article III of these Restated Articles of Incorporation, authority is
expressly vested in the board of directors of the corporation to establish
series of unissued shares of any class by fixing and determining the
designations, preferences, limitations and relative rights, including voting
rights, of the shares of any series so established to the same extent that such
designations, preferences, limitations and relative rights could be stated if
fully set forth in the Restated Articles of Incorporation.

In accord with Article 2.13(c) of the Texas Business Corporation Act and
pursuant to Article III of these Restated Articles of Incorporation, authority
is expressly vested in the board of directors to eliminate from the Restated
Articles of Incorporation any series of capital stock referenced therein,
provided that no shares of capital stock were issued or because no issued shares
of such series remain outstanding. To eliminate such series, the board of
directors shall adopt a resolution to this effect and all eliminated shares
shall resume the status of authorized but unissued shares of any eliminated
class.

Section B. The Common Stock shall consist of 75,000,000 shares, $0.001 par value
per share. Subject to the rights of holders of stock of the corporation senior
to the Common Stock with respect to the declaration and payment of dividends,
holders of Common Stock shall be entitled to receive such dividends and other
distributions in cash, stock or property of the corporation as may be declared
thereon by the board of directors from time to time out of assets or funds of
the corporation legally available therefor. At every meeting of the shareholders
of the corporation, every holder of Common Stock shall be entitled to one vote
in person or by proxy for each share of Common Stock standing in his name on the
transfer books of the corporation.


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Section C. The Preferred Stock shall consist of 15,000,000 shares, $0.001 par
value per share.

                  1. The Preferred Stock may, from time to time, be divided into
         and issued in one or more series, with each series to be so designated
         as to distinguish the shares thereof from the shares of all other
         series. The shares of each series may have such powers, designations,
         preferences, relative rights, qualifications, limitations or
         restrictions as are stated herein and in one or more resolutions
         providing for the issue of such series adopted by the board of
         directors of the corporation as provided in this Section C.

                  2. To the extent that these Restated Articles of Incorporation
         do not fix and determine the variations in the relative rights and
         preferences of the Preferred Stock, both in relation to the Common
         Stock and as between series of Preferred Stock, the board of directors
         is expressly vested with the authority to divide the Preferred Stock
         into one or more series and, within the limitations set forth in these
         Restated Articles of Incorporation, to fix and determine the relative
         rights and preferences of the shares of any series so established and,
         with respect to each such series, to fix by one or more resolutions
         providing for the issue of such series, the following:

                           (a) The distinctive designation of, and the number of
                  shares of Preferred Stock which shall constitute, the series,
                  which number may be increased or decreased (but not below the
                  number of shares thereof then outstanding) from time to time
                  by action of the board of directors.

                           (b) The dividend rate, if any, on the shares of such
                  series and the date or dates from which dividends shall
                  commence to accrue or accumulate, the terms and conditions
                  upon which dividends, if any, on the shares of such series
                  shall be paid, and whether or in what circumstances such
                  dividends shall be cumulative.

                           (c) The price at and the terms and conditions on
                  which the shares of such series may be redeemed, including
                  (without limitation) the time during which shares of the
                  series may be redeemed and the premium, if any, over and above
                  the par value thereof that the holders of shares of such
                  series shall be entitled to receive upon the redemption
                  thereof, which premium may vary at different dates and may
                  also be different with respect to shares redeemed through the
                  operation of any retirement or sinking fund.

                           (d) The liquidation preference, if any, over and
                  above the par value thereof that the holders of shares of such
                  series shall be entitled to receive upon the voluntary or
                  involuntary liquidation, dissolution or winding-up of the
                  affairs of the corporation.

                           (e) Whether or not the shares of such series shall be
                  subject to the operation of a retirement or sinking fund, and,
                  if so, the extent and manner in which any such retirement or
                  sinking fund shall be applied to the purchase or redemption of


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                  the shares of such series for retirement or for other
                  corporate purposes, and the terms and provisions of such
                  retirement or sinking fund.

                           (f) The terms and conditions, if any, on which the
                  shares of such series shall be convertible into, or
                  exchangeable for, shares of any other class or classes of
                  capital stock of the corporation or any series of any other
                  class or classes, or of any other series of the same class,
                  including (without limitation) the price or prices or the rate
                  or rates of conversion or exchange and the method, if any, of
                  adjusting the same; provided, that shares of such series may
                  not be convertible into shares of a series or class that has
                  prior or superior rights and preferences as to dividends or
                  distribution of assets of the corporation upon voluntary or
                  involuntary liquidation, dissolution or winding-up of the
                  affairs of the corporation.

                           (g) The voting rights, if any, on the shares of such
                  series (in addition to voting rights provided by law).

                           (h) Any or all other preferences and relative,
                  participating, optional or other special rights, or
                  qualifications, limitations or restrictions thereof, as shall
                  not be inconsistent with the law or with this Article III.

                  3. All shares of any one series of Preferred Stock shall be
         identical with each other in all respects, except that shares of any
         one series issued at different times may differ as to the dates from
         which dividends thereon, if any, shall commence to accrue or
         accumulate; and all series shall rank equally and be identical in all
         respects, except as permitted by this Section C.

                  4. Except as provided in the resolution or resolutions adopted
         by the board of directors providing for the issue of the series of
         Preferred Stock, no vote or consent of the holders of outstanding
         shares of that series shall be required for the issue by the board of
         directors of any other series of Preferred Stock, whether or not the
         rights and preferences of any such other series shall be fixed by the
         board of directors as senior to, or on a parity with, the rights and
         preferences of that outstanding series.

                                   ARTICLE IV

Responsibility for the management of the business and conduct of the affairs of
the corporation shall be vested in the board of directors. In furtherance and
not in limitation of the powers conferred by the laws of the State of Texas, the
board of directors is expressly authorized:

         (A) Pursuant to Article 2.23 of the Texas Business Corporation Act, to
adopt bylaws for the corporation and to alter, amend and repeal said bylaws,
subject only to any limitations imposed by the Texas Business Corporation Act,
which reserves a power exclusively to the shareholders, whether in whole or in
part;


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         (B) To include in said bylaws any provision for the regulation and
management of the affairs of the corporation not inconsistent with the Texas
Business Corporation Act or these Restated Articles of Incorporation; and

         (C) To adopt a corporate seal.

                                    ARTICLE V

The corporation may, upon adoption of a resolution by its board of directors,
purchase its own shares to the extent of unreserved and unrestricted capital
surplus available therefor. The board of directors of the corporation may, from
time to time, in its discretion and without the prior approval of the
shareholders of the corporation, distribute a portion of its assets to the
shareholders out of capital surplus of the corporation.

                                   ARTICLE VI

Subject to the provisions hereof, the corporation reserves the right, at any
time and from time to time, to amend, alter, repeal, or rescind any provision
contained herein in the manner now or hereafter prescribed by law; and other
provisions authorized by the laws of the State of Texas at the time in force may
be added or inserted in the manner now or hereafter prescribed by law; and all
rights, preferences and privileges of whatsoever nature conferred upon
shareholders, directors or any other persons whomsoever by and pursuant to these
Restated Articles of Incorporation in its present form or as hereafter amended
are granted subject to this reservation.

                                   ARTICLE VII

In furtherance and not in limitation of the powers conferred by statute, the
board of directors is expressly authorized by a majority of the whole board of
directors to designate one or more committees, each committee to consist of one
or more of the directors of the corporation. Any such committee, to the extent
provided in the resolution or in the bylaws of the corporation, shall have and
may exercise the powers of the board of directors in the management of the
business and affairs of the corporation and may authorize the seal of the
corporation to be affixed to all papers which may require it; provided, however,
the bylaws may provide that in the absence or disqualification of any member of
such committee or committees, the member or members thereof present at any
meeting and not disqualified from voting, whether or not he or they constitute a
quorum, may unanimously appoint another member of the board of directors to act
at the meeting in the place of such absent or disqualified member.

                                  ARTICLE VIII

The board of directors is expressly authorized to create and issue rights
entitling the holders of such rights to purchase from the corporation shares of
capital stock or other securities or property. The board of directors shall
have, in its sole discretion, the authority to determine the time at which and
terms upon which such rights are to be issued and set forth in the contracts or
instruments that evidence such rights.


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                                   ARTICLE IX

A director of the corporation shall not be personally liable to the corporation
or its shareholders for monetary damages for breach of duty or care or other
duty as a director, except for liability for (i) any appropriation, in violation
of his duties, of any business opportunity of the corporation; (ii) acts or
omissions not in good faith or which involve intentional misconduct or a knowing
violation of law; (iii) any type of liability not contemplated by the Texas
Business Corporation Act; or (iv) any transaction from which the director
derived an improper personal benefit. If the Texas Business Corporation Act is
hereafter amended to authorize further elimination or limitation of the
liability of the directors, then the liability of the director shall be
eliminated or limited to the fullest extent permitted by the law of Texas, as
amended. In addition to the limitation on personal liability of directors
provided herein, the corporation shall, to the fullest extent permitted by the
Texas Business Corporation Act, indemnify its officers and directors and advance
expenses incurred by such officers or directors in relation to any action, suit
or proceeding. Any repeal or modification of this Article IX by the shareholders
of the corporation shall be prospective only and shall not adversely affect any
limitation on the personal liability or right to indemnification or advancement
of expenses hereunder existing at the time of such repeal or modification.

                                    ARTICLE X

The street address of the registered office of the corporation is 1601 Elm
Street, Suite 3000, Dallas, Texas 75201, and the name of the registered agent of
the corporation at such address is David G. McLane.


         IN WITNESS HEREOF, the undersigned has executed these Restated Articles
of Incorporation on March 9, 2000.

                                            MICRO-ASI, INC.



                                            By: /s/ JOEL E. CLAYBROOK
                                               --------------------------------
                                                Joel E. Claybrook, President



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