In S110 SoftDevice, NRF_POWER->SYSTEMOFF is written. Why?

RE: In S110 SoftDevice, NRF_POWER->SYSTEMOFF is written. Why?

Yokoyama, Atsushi — Fri, 13 Mar 2015 01:49:36 GMT

I could resolve the problem. Thanks, Ulrich! I found the following sections in the "nRF51 Series Reference Manual Version 3.0." In the section "14.1 Functional description", we see

When the correct level is detected on any such configured pin, the sense mechanism will set the DETECT signal high.
POWER: uses the DETECT signal to exit from System OFF

and in the section "12.1.5 System OFF mode", we see

The system can be woken up from System OFF mode either from the DETECT signal (when active) generated by the GPIO peripheral

I understood the specification. Thanks and Regards, Atsushi

RE: In S110 SoftDevice, NRF_POWER->SYSTEMOFF is written. Why?

Yokoyama, Atsushi — Thu, 12 Mar 2015 23:59:29 GMT

Thank you! I'll take care of that.

Regards,

Atsushi

RE: In S110 SoftDevice, NRF_POWER->SYSTEMOFF is written. Why?

Mathias — Thu, 12 Mar 2015 12:29:45 GMT

Don't forget to update to SDK 8.0.0 before, otherwise it won't work. Had the same issue since there was a new softdevice available but no SDK to support it for some time!

BR Mathias

RE: In S110 SoftDevice, NRF_POWER->SYSTEMOFF is written. Why?

Yokoyama, Atsushi — Thu, 12 Mar 2015 11:21:48 GMT

Hi Mathias,

Thank you for commenting! The reason why I'm sticking to the version is, unfortunately the 8.0.0 demo code did not work at all in my environment. I was thinking I should try 8.0.0 later again when my application worked fine based on the 7.x.0. (I need to run the my application for a customer demo ASAP...)

Thanks again and Best Regards,

Atsushi

RE: In S110 SoftDevice, NRF_POWER->SYSTEMOFF is written. Why?

Yokoyama, Atsushi — Thu, 12 Mar 2015 11:21:24 GMT

Hi Ulrich,

Thank you for the prompt answer! I'm afraid I didn't notice the code and the comment. I was reading the "S110 nRF51822 SoftDevice Specification" document only... I should have gone through the code entirely prior to panic. (I didn't image that CPU would restart by any reason if it once went to the HardFault. I'm new to ARM Cortex-M.)

I will try the keypress tomorrow as you pointed out.

Thanks and Best Regards,

Atsushi

RE: In S110 SoftDevice, NRF_POWER->SYSTEMOFF is written. Why?

Ulrich Myhre — Thu, 12 Mar 2015 09:30:14 GMT

The SYSTEMOFF will be triggered at that point in the SoftDevice if you call sd_power_system_off(). This happens at line 709 in the app you are using, in the on_ble_evt handler:

case BLE_GAP_EVT_TIMEOUT:
        if (p_ble_evt->evt.gap_evt.params.timeout.src == BLE_GAP_TIMEOUT_SRC_ADVERTISEMENT)
        {
            nrf_gpio_pin_clear(ADVERTISING_LED_PIN_NO);

            // Go to system-off mode (this function will not return; wakeup will cause a reset).
            err_code = sd_power_system_off();
            APP_ERROR_CHECK(err_code);
        }
        break;

Is this what you are seeing? The purpose for this example is to enable advertisements for some time after startup, then shut down and wait for a keypress if no connection is established within the time limits.

RE: In S110 SoftDevice, NRF_POWER->SYSTEMOFF is written. Why?

Mathias — Thu, 12 Mar 2015 07:43:22 GMT

Hi Atsushi,

sorry for hijacking your thread but I am having similar issues with the nrF51822 QFAA Gx0 (0x3C) using the softdevice 8.0.0. (Hangup after some time)

Is there a reason why you are staying on 7.1.0, because when looking at nRF51 Series Compatibility Matrix in Version 1.2 a nRF51 IC rev. of 3 is recommended for a softdevice > 7.0.0 anyway.

In the release notes of the S110 in rev. 8.0.0 it is only noted that IC rev. 1 is not supported anymore.

It would be very interresting to get an information what if there are any limitations when using softdevice version > 7.0.0 with IC ref. 2.

BR Mathias