UNITED STATES
                     SECURITIES AND EXCHANGE COMMISSION
                           Washington, D.C.  20549

                                SCHEDULE 13G

                 Under the Securities Exchange Act of 1934

                             (Amendment No. __4__)*

                            Datakey, Incorporated
- ------------------------------------------------------------------------------
                              (Name of Issuer)

                                Common Stock
- ------------------------------------------------------------------------------
                       (Title of Class of Securities)

                                237909-10-6
- ------------------------------------------------------------------------------
                              (CUSIP Number)

                             December 31, 1999
- ------------------------------------------------------------------------------
          (Date of Event Which Requires Filing of this Statement)

Check the appropriate box to designate the rule pursuant to which this Schedule
is filed:

     /X/   Rule 13d-1(b)
     /_/   Rule 13d-1(c)
     /_/   Rule 13d-1(d)


*The remainder of this cover page shall be filled out for a reporting person's
initial filing on this form with respect to the subject class of securities, and
for any subsequent amendment containing information which would alter the
disclosures provided in a prior cover page.

The information required in the remainder of this cover page shall not be deemed
to be "filed" for the purpose of Section 18 of the Securities Exchange Act of
1934 ("Act") or otherwise subject to the liabilities of that section of the Act
but shall be subject to all other provisions of the Act (however, see the
Notes).



SEC 1745 (2/92)              Page 1 of 5 pages



CUSIP No.  237909-10-6              13G               Page 2 of 5 pages

1     NAME OF REPORTING PERSON
      S.S. OR I.R.S. IDENTIFICATION NO. OF THE ABOVE PERSON

             Perkins Capital Management, Inc.
             IRS ID No.: 41-1501962

2    CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*
                                               (a) /_/
                                               (b) /_/

3    SEC USE ONLY

4    CITIZENSHIP OR PLACE OF ORGANIZATION

            730 East Lake Street, Wayzata, MN  55391-1769

NUMBER OF SHARES         5    SOLE VOTING POWER
                              300,997

BENEFICIALLY OWNED       6    SHARED VOTING POWER
                              0

BY EACH REPORTING        7    SOLE DISPOSITIVE POWER
                              1,213,725

PERSON WITH              8    SHARED DISPOSITIVE POWER
                              0
9    AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
     1,213,725

10   CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES*


11   PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9
     21.0%

12   TYPE OF REPORTING PERSON*
     IA


SEC 1745    (2/92)               Page 2 of 5 pages




CUSIP No.  237909-10-6                 13G              Page 3 of 5 pages


Item 1.
     (a) Name of Issuer
         Datakey, Incorporated

     (b) Address of Issuer's Pricipal Executive Offices
         407 West Travelers Trail, Burnsville, MN  55337
Item 2.
     (a) Name of Person Filing
         Perkins Capital Management, Inc.

     (b) Address of Principal Business Office or, if none, residence
         730 East Lake Street
         Wayzata, MN  55391-1769

     (c) Citizenship
         Minnesota Corporation

     (d) Title of Class of Securities
         Common Stock

     (e) CUSIP Number
         237909-10-6

Item 3.  If this statement is filed pursuant to Rule 13d-1(b), or 13d-2(b),
         check whether the person filing is a:

      (a) /_/     Broker or Dealer registered under Section 15 of the Act

      (b) /_/     Bank as defined in section 3 (a) (6) of the Act

      (c) /_/     Insurance Company as defined in section 3 (a) (6) of the Act

      (d) /_/     Investment Company registered under section 8 of the
                  Investment Company Act.

      (e) /X/    Investment Adviser registered under section 203 of the
                 Investment Advisers act of 1940

      (f) /_/     Employee Benefit Plan, Pension Fund which is subject to the
                  provisions of the Employee Retirement Income Security Act
                  of 1974 or Endowment Fund; see 240.13d-1 (b) (1) (ii) (F)

      (g) /_/     Parent Holding Company, in accordance with
                  240.13d-1 (b) (ii) (G)  (Note:  See Item 7)


SEC 1745 (2/92)                 Page 3 of 5 pages




CUSIP No.  237909-10-6                13G               Page 4 of 5 pages

     (h) /_/     Group, in accordance with 240.13d-1(b) (1) (ii) (H)

Item 4.  Ownership

If the percent of the class owned, as of December 31 of the year covered by
the statement, or as of the last day of any month described in Rule 13d-1
(b) (2), if applicable, exceeds five percent, provide the following
information as of that date and identify those shares which there is a right
to acquire.

     (a)     The amount beneficially owned is 1,213,725 (includes 1,027,025
             common equivalents and 186,700 warrants, exercisable within
             60 days).

     (b)     The percent of class is 21.0%

     (c)     Number of shares as to which such person has:
             (i)    sole power to vote or to direct the vote
                    300,997
             (ii)   shared power to vote or to direct the vote
                    0
             (iii)  Perkins Capital Management, Inc. has the sole power to
                    dispose of 1,213,725 (includes 1,027,025 common equivalents
                    and 186,700 warrants, exercisable within 60 days).
             (iv)   shared power to dispose or to direct the disposition of
                    0

Item 5.  Ownership of Five Percent or Less of a Class
         Not applicable.

Item 6.  Ownership of more than Five Percent on Behalf of Another Person.
         None

Item 7.  Identification and Classification of the Subsidiary Which Acquired
         the Security Being Reported on By the Parent Holding Company
         None

Item 8.  Identification and Classification of Members of the Group
         None

Item 9.  Notice of Dissolution of Group
         None


SEC 1745 (2/92)                   Page 4 of 5 pages




CUSIP No.  237909-10-6                   13G              Page 5 of 5 pages


Item 10.  Certification

          By signing below I certify that, to the best of my knowledge and
          belief, the securities referred to above were acquired in the
          ordinary course of business and were not acquired for the purpose
          of and do not have the effect of changing or influencing the
          control of the issuer of such securities and were not acquired in
          connection with or as a participant in any transaction having such
          purposes or effect.

After reasonable inquiry and to the best of my knowledge and belief, I
certify that the information set forth in this statement is true, complete
and correct.


January 31, 2000
- ----------------------------------------
Date

By   /s/ Richard C. Perkins
- ----------------------------------------
            Signature

Richard C. Perkins, VP/Port Mgr
- ----------------------------------------
           Name/Title


SEC 1745 (2/92)                  Page 5 of 5 pages