zephyr pwm sequence

[Jay]

In SDK 15 I was able to build a 3 output arbitrary waveform generator using a pwm module in sequence mode. 

Is this possible with the Zephyr pwm API?

If so Is there an example of this somewhere using the Zephyr API?

Or do I need to bypass zephyr and hook into the nrfx device driver directly?

  

[Jay]

In the old SDK the irq defines such as APP_IRQ_PRIORITY_LOWEST were defined in the  in the file app_util_platform.h.

In the new ncs SDK where can I find the irq defines?

[Einar Thorsrud]

The interrupt priority comes from the devicetree file. For PWM0 on the nRF52833 you have this section in zephyr/dts/arm/nordic/nrf52833.dtsi (there are also similar for the other PWM instances):

		pwm0: pwm@4001c000 {
			compatible = "nordic,nrf-pwm";
			reg = <0x4001c000 0x1000>;
			interrupts = <28 NRF_DEFAULT_IRQ_PRIORITY>;
			status = "disabled";
			label = "PWM_0";
			#pwm-cells = <3>;
		};

The default priority is 1. If you want to change the interrupt priority, you can make an overlay file for your board where you set a different priority. The PWM related part would then be something like this (here the priority is set to 0, adjust as needed):

&pwm0 {
	interrupts = <28 0>;
};