NRF52805 BLE and PWM

RE: NRF52805 BLE and PWM

MsaYpsomed — Thu, 24 Jun 2021 10:07:12 GMT

Heija Carl,

thanks for your answer. I could fix our problem with adding the ppi-base line. Infact We had to change it to

ppi-base = <11>

Now it works as intended.

Best regards,

Marc

RE: NRF52805 BLE and PWM

Carl Richard — Wed, 23 Jun 2021 10:37:54 GMT

Hello again!

You can change the PPI base used by the SW PWM using a DTS overlay. In this case add the file "nrf52dk_nrf52805.overlay" to the project, containing the following code:

&sw_pwm {
    status = "okay";
    ppi-base = <10>;
};

This sets the "ppi-base" to 10, as the previous channels are used by the radio.

One note. I see that you have enabled "CONFIG_BT_LL_SW_SPLIT=y", which forces the application to use the Zephyr Bluetooth LE controller. I did not see the error when using Nordic's Softdevice Controller (used by default on nRF5x devices), so you could consider doing that instead.

Best regards,
Carl Richard

RE: NRF52805 BLE and PWM

MsaYpsomed — Tue, 22 Jun 2021 05:50:29 GMT

Heija Carl,

thanks for your help. I got the driver configuration from the zephyr samples:

- BLE: beacon

- PWM: fade_led

I later found in a post, that they suggest using CONFIG_PWM_NRF5_SW for softwarebased pwm, since the NRF52805 does not have an hardware implemented pwm module.

Best regards,

Marc

RE: NRF52805 BLE and PWM

Carl Richard — Mon, 21 Jun 2021 14:50:58 GMT

Hello!

Thanks for reaching out. I will take a look at this. In the meantime, may I ask why you're using a legacy driver and not nRFX? (since CONFIG_PWM_NRF5_SW is enabled)

Best regards,
Carl Richard