Timer is not stable(phase/duty change all the time).

[Stanley]

Dears, I am working for an application on [email protected] including PWM, Timer and a few peripheral functions. I was trying to create a timer on timer1 in us tick. The timer was created, but not stable. I implemented a pin toggle in timer even handler to check the timer stability. The only way to get a stable output pin toggle signal is that set the timer priority to 1(original is 3), but it will cause the system crash. Is there any mistake I implemented the timer for us application?

---

void sTimerInit(void) { uint32_t time_us = 20; //Time(in micro-seconds) between consecutive compare events. uint32_t time_ticks; uint32_t err_code = NRF_SUCCESS;

//Configure TIMER_LED for generating simple light effect - leds on board will invert his state one after the other.
nrf_drv_timer_config_t timer_cfg = NRF_DRV_TIMER_DEFAULT_CONFIG;
err_code = nrf_drv_timer_init(&TIMER_COUNTER_IR, &timer_cfg, timer_led_event_handler);
APP_ERROR_CHECK(err_code);

time_ticks = nrf_drv_timer_us_to_ticks(&TIMER_COUNTER_IR, time_us);

nrf_drv_timer_extended_compare(
     &TIMER_COUNTER_IR, NRF_TIMER_CC_CHANNEL0, time_ticks, NRF_TIMER_SHORT_COMPARE0_CLEAR_MASK, true);

nrf_drv_timer_enable(&TIMER_COUNTER_IR);

}

[FormerMember]

Could you share more of your code so that it is easier to get an overview?

It is most likely not related, but what is the value returned by nrf_drv_timer_us_to_ticks()? From what I can see, the arguments should be the time in microseconds and the frequency of the timer..

[Stanley]

Hello Kristin, Thanks for your reply. Should I open the complete C code to you? Please let me know if any questions. I have doubt as you mentioned. But also as I mentioned, it will get stable when I changed the priority of Timer to 1.(// Priorities 0,2 (nRF51) and 0,1,4,5 (nRF52) are reserved for SoftDevice) The value from nrf_drv_timer_us_to_ticks() is 0x140. I think it could the reason of the other timers againsting the timer1 when I set it as priority 3.

[FormerMember]

I would only need the relevant part of main.c, so I can test it here.

[Stanley]

I separate the original main.c to several c files. I can send it to you for reference. Where should I send to?

[FormerMember]

You can create a new support case on myPage from www.nordicsemi.com, upload the file there and refer to this thread.

[Stanley]

I have tried on the nRF52 EVB(pca10040) to check this issue. It also came out. I will upload the file(main.c) for your reference.