Timer Pulse Output Function (timers 2, 3)

Settings for the timer pulse output function are listed below. Timer 2 is used as an example.

(1)Set the TM2EN flag of the timer 2 mode register (TM2MD) to "0" to stop the count operation of timer 2.

(2)Set bit 2 of the port 1 output/input mode register (P1OMD) to "1" to set the special function pin. Bit 2 of port 1 will be specified as the pulse output pin.

(3)Set the TM2CK2 to 0 flags of the TM2MD register to select fs, fs/4, fx, or synchronized fx as the clock source.

(4)Set the TM2PWM flag of the TM2MD register to "0" so that normal timer operation is selected.

(5)Set a value in compare register 2 (TM2OC).

(6)Set the TM2EN flag of the TM2MD register to "1" to start the timer.

(7)When timer 2 begins operation, binary counter 2 will count upward from X'00'.

(8)When the value of binary counter 2 matches that of the TM2OC register, the timer 2 interrupt request flag is set, and the binary counter 2 is reset to X'00' and begins to count upward again.

Matches compare register

Binary counter

TM2OUT

Figure 4-2-3 Timer Pulse Output Timing

Chapter 4 Timer Functions

The period of a signal output to the port is 1/2 of the period set in the TM2OC register.

If port 1 is to be used as a pulse output pin, it is necessary to set the port 1 output direction control register (P1DIR) and the port 1 pull-up/pull-down resistor control register (P1PLU).

8-bit Timer Operation (timers 2, 3)

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Panasonic MN101C00 user manual Timer Pulse Output Timing, Matches compare register Binary counter