CHAPTER 7 INTERRUPT/EXCEPTION PROCESSING FUNCTION
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User’s Manual U15195EJ5V0UD
(4) Timer 2 input filter mode registers 0 to 5 (FEM0 to FEM5)
These registers specify the valid edge for external interrupts input to timer 2 (INTP20 to INTP25). The
correspondence between each register and the external interrupt request that register controls is shown
below.
•
FEM0: INTP20
•
FEM1: INTP21
•
FEM2: INTP22
•
FEM3: INTP23
•
FEM4: INTP24
•
FEM5: INTP25
The valid edge can be specified independently for each pin (rising edge, falling edge, or both rising and falling
edges).
These registers can be read/written in 8-bit or 1-bit units.
Cautions 1. Be sure to clear (0) the STFTE bit of timer 2 clock stop register 0 (STOPTE0) even when
using the TI2/INTP20, TO21/INTP21, TO22/INTP22, TO23/INTP23, TO24/INTP24, and
TCLR2/INTP25 pins as INTP20, INTP21, INTP22, INTP23, INTP24, and INTP25,
respectively, even if not using timer 2.
2. Setting the trigger mode of the INTP2n pin should be performed after setting the PMC2
register.
If the PMC2 register is set after setting the FEMn register, an invalid interrupt may occur
when the PMC2 register is set (n = 0 to 5).
3. The noise elimination function starts operating by setting the CEEn bit of the TCRE0
register to 1 (enabling count operations).