Can I use two RTC in nRF5340?

[Carl Sun]

Hello,

In nRF5340 I use one RTC and it works. Here is my code:

1) in prj.conf:

CONFIG_NRFX_RTC=y
CONFIG_NRFX_RTC0=y

2) in the code:

a) define:
nrfx_rtc_t sti_period_rtc_0 = NRFX_RTC_INSTANCE(0);

b):

IRQ_CONNECT(DT_IRQN(DT_NODELABEL(rtc0)),
DT_IRQ(DT_NODELABEL(rtc0), priority),
nrfx_isr, nrfx_rtc_0_irq_handler, 0);

nrfx_rtc_config_t period_rtc_0_config = NRFX_RTC_DEFAULT_CONFIG;

period_rtc_0_config.prescaler = 0;

nrfx_rtc_init( &sti_period_rtc_0, &period_rtc_0_config, period_rtc_0_handler );

==================================================

Now I want to use two RTC, so I add :

1) in prj.conf:

CONFIG_NRFX_RTC=y
CONFIG_NRFX_RTC0=y
CONFIG_NRFX_RTC1=y

2) in the code:

a) define:
nrfx_rtc_t sti_period_rtc_0 = NRFX_RTC_INSTANCE(0);

nrfx_rtc_t sti_period_rtc_1 = NRFX_RTC_INSTANCE(1);

b)

IRQ_CONNECT(DT_IRQN(DT_NODELABEL(rtc0)),
DT_IRQ(DT_NODELABEL(rtc0), priority),
nrfx_isr, nrfx_rtc_0_irq_handler, 0);

nrfx_rtc_config_t period_rtc_0_config = NRFX_RTC_DEFAULT_CONFIG;

period_rtc_0_config.prescaler = 0;

nrfx_rtc_init( &sti_period_rtc_0, &period_rtc_0_config, period_rtc_0_handler );

/////////////////////////////////////

IRQ_CONNECT(DT_IRQN(DT_NODELABEL(rtc1)),
DT_IRQ(DT_NODELABEL(rtc1), priority),
nrfx_isr, nrfx_rtc_1_irq_handler, 0);

nrfx_rtc_config_t period_rtc_1_config = NRFX_RTC_DEFAULT_CONFIG;

period_rtc_1_config.prescaler = 0;

nrfx_rtc_init( &sti_period_rtc_1, &period_rtc_1_config, period_rtc_1_handler );

///////////////////
then I run Project->run CMake in SEGGER EMbedded studio
and I got this error:

1> Combining ‘zephyr/isr_tables.c’
1> gen_isr_tables.py: error: multiple registrations at table_index 21 for irq 21 (0x15)
1> Existing handler 0x16d05, new handler 0x57e5
1> Has IRQ_CONNECT or IRQ_DIRECT_CONNECT accidentally been invoked on the same irq multiple times?

Can you help to solve this problem? how can I use two RTC in nRF5340?

Thanks.

Carl

[Sigurd]

Hi,

Maybe you can try this instead, snippet:

	
	IRQ_CONNECT(RTC0_IRQn, NRFX_RTC_DEFAULT_CONFIG_IRQ_PRIORITY,
		nrfx_rtc_0_irq_handler, NULL, 0);

			IRQ_CONNECT(RTC1_IRQn, NRFX_RTC_DEFAULT_CONFIG_IRQ_PRIORITY,
		nrfx_rtc_1_irq_handler, NULL, 0);

(If this does not work either, then please upload your project.)

[Carl Sun]

By the way, I already used 3 timers and 1 GPIO as below:

IRQ_CONNECT(DT_IRQN(DT_NODELABEL(timer0)),
DT_IRQ(DT_NODELABEL(timer0), priority),
nrfx_isr, nrfx_timer_0_irq_handler, 0);

IRQ_CONNECT(DT_IRQN(DT_NODELABEL(timer1)),
DT_IRQ(DT_NODELABEL(timer1), priority),
nrfx_isr, nrfx_timer_1_irq_handler, 0);

IRQ_CONNECT(DT_IRQN(DT_NODELABEL(timer2)),
DT_IRQ(DT_NODELABEL(timer2), priority),
nrfx_isr, nrfx_timer_2_irq_handler, 0);

IRQ_CONNECT(DT_IRQN(DT_NODELABEL(gpiote)),
DT_IRQ(DT_NODELABEL(gpiote), priority),
nrfx_isr, nrfx_gpiote_irq_handler, 0);

Is this the reason why I got those errors when I tried to register the second RTC?

Thanks.

Carl..

[Sigurd]

You are getting this error because RTC1 is reserved and used by the Zephyr RTOS kernel timer:

https://github.com/nrfconnect/sdk-zephyr/blob/v2.6.0-ncs1-rc3/drivers/timer/Kconfig#L158

I would recommend looking into using the Zephyr RTOS kernel timer for implementing application timers:

https://docs.zephyrproject.org/latest/reference/kernel/timing/timers.html

[Carl Sun]

Hi, understood, Thanks for your help.

In this one RTC, do we have two channels? Can I use two channels?

If yes, can the two channels have two different period( generate two enents)?

Thanks.

[Sigurd]

Hi,

Yes, you have 4 CC Compare register, CC[n] (n=0..3), so you can get 4 different events, EVENTS_COMPARE[n] (n=0..3) , based on what CC register you are using.

[Carl Sun]

Thanks,

Do you have some code example on how to use one RTC with two or several compare channels?

enable, disable, start, stop, update, or event handler of the channels.

Thanks.

Carl.

[Carl Sun]

Does that mean: if the content of the CC Compare register is different, then the duration(period) is different?

Thanks.