INT 1Ch (28)             User Timer Tick

Called at every timer tick (18.2 times per second, or every 55 ms) by
INT 08h (System Timer).

                                                                          

By default, the interrupt handler for this interrupt IRETs back to the
caller. The user can supply his own handler so he can attain control
at every timer tick.

Notes:         Note that this interrupt is called by the hardware
timer interrupt (INT 08h), which has not signaled
the end of the interrupt back to the interrupt
controller. Therefore, this routine is limited in
the actions it can take, since all interrupts will
be disabled. A better approach to this problem is to
intercept INT 08h. The new INT 08h handler will
first call the standard INT 08h, which will handle
the interrupt controller completion signals
mentioned above. Then after the standard INT 08h is
completed, the new handler can do whatever it has to
do at every timer tick.

See also: INT 08h

INT 1Ch (28) User Timer Tick