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INT 16h,  03h (3)        Set Typematic Rate                  PCjr, XT-286, AT

    Sets the typematic rate and delay of the keyboard.

       On entry:      AH         03h
                      AL         Subservice
                                    0 - Return to default keyboard state
                                    1 - Increase initial delay
                                    2 - Slow typematic rate by 1/2
                                    3 - Perform Subservices 1 and 2
                                    4 - Turns off typematic characters
                                    5 - Set typematic rate and delay
                                        BL - Typematic rate (see below)
                                        BH - Delay value (see below)

       Returns:       None

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  Typematic Rate in Characters per Second (BL)

     BL        Rate              BL        Rate              BL        Rate
     00h       30.0              0Bh       10.9              16h        4.3
     01h       26.7              0Ch       10.0              17h        4.0
     02h       24.0              0Dh        9.2              18h        3.7
     03h       21.8              0Eh        8.6              19h        3.3
     04h       20.0              0Fh        8.0              1Ah        3.0
     05h       18.5              10h        7.5              1Bh        2.7
     06h       17.1              11h        6.7              1Ch        2.5
     07h       16.0              12h        6.0              1Dh        2.3
     08h       15.0              13h        5.5              1Eh        2.1
     09h       13.3              14h        5.0              1Fh        2.0
     0Ah       12.0              15h        4.6

  Delay Value in Milliseconds (BH)

          BH             Delay
           0              250
           1              500
           2              750
           3             1000

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       Notes:         Subservices 0 through 4 are available only for the
                      PCjr. Subservice 5 is available only for ATs dated
                      11/15/85 and after, and for XT-286s.

                      Subservice 0 (Return to Default Keyboard State)
                      restores the keyboard to its original state. The
                      original state at power-on is typematic on, normal
                      initial delay and normal typematic rate.

                      Subservice 1 (Increase Initial Delay) increases the
                      delay between the first character typed and the
                      burst of typematic characters.

                      For Subservices 0 through 4, each time the typematic
                      rate is changed, all previous states are removed.
                      For example, if you want to increase the typematic
                      delay and the rate is currently being slowed, use
                      Subservice 3 (Perform Subservices 1 and 2) rather
                      than Subservice 1 (Increase Initial Delay) by
                      itself.