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As of 2025-11-07

Timer0 .. 4

Timer, PWM (mwx::periph_timer)

Timers have two functions: generating software interrupts at specified intervals and producing PWM output at specified intervals. The TWELITE wireless module provides five timers, from 0 to 4.

Although the embedded object names are Timer0..4, this page refers to them as TimerX.

Methods

`setup()`

void setup()

Initializes the timer. This call allocates the required memory area.

`begin()`

void begin(uint16_t u16Hz, bool b_sw_int = true, bool b_pwm_out = false)

Starts the timer. The first parameter specifies the timer frequency in Hz. If the second parameter is set to true, software interrupts are enabled. If the third parameter is set to true, PWM output is enabled.

You can change the frequency with change_hz(). This method allows more precise control than begin().

You can modify the PWM duty cycle using change_duty().

To describe the interrupt handler process, you need to define Application Behavior.

`end()`

void end()

Stops the timer operation.

`available()`

inline bool available()

Becomes true in the loop() immediately after a timer interrupt occurs, and turns false after the loop() finishes.

`change_duty()`

void change_duty(uint16_t duty, uint16_t duty_max = 1024)

Sets the duty cycle. The first parameter specifies the duty value (a smaller value brings the average waveform level closer to GND, while a larger value brings it closer to Vcc). The second parameter specifies the maximum duty value.

It is recommended to set duty_max to one of 1024, 4096, or 16384.

Although internal count value calculations involve division, these three values allow bit-shift operations instead. Other values result in heavier division calculations.

`change_hz()`

void change_hz(uint16_t hz, uint16_t mil = 0)

Sets the timer frequency. The second parameter specifies the fractional part (three decimal places) of the frequency as an integer. For example, to set 10.4 Hz, specify hz=10, mil=400.