Program hangs in sd_softdevice_enable

[Cyril Hruscak]

Hello,

I'm trying to start softdevice on a custom board with nRF51822 chip and S110 device. The code hangs in SOFTDEVICE_HANDLER_INIT. It seems that EVENTS_LFCLKSTARTED is never set.

Here's the used part of the code:

// Start 32 MHz crystal oscillator NRF_CLOCK->XTALFREQ = 0; NRF_CLOCK->EVENTS_HFCLKSTARTED = 0; NRF_CLOCK->TASKS_HFCLKSTART = 1; // Wait for the external oscillator to start up while (NRF_CLOCK->EVENTS_HFCLKSTARTED == 0) {} SOFTDEVICE_HANDLER_INIT(NRF_CLOCK_LFCLKSRC_RC_250_PPM_4000MS_CALIBRATION, false);

The problem is there also without debugger. What could be wrong?

Best regards, Cyril.

[Ole Morten]

This sounds very strange. Normally, there shouldn't be any problems like this when using the RC oscillator. Have you checked to see if sd_ble_softdevice_enable() returns any error code? That's easiest done by following the procedure described here, regarding app_error_handler(). Also, if you run your project with a debugger, let it run freely from reset, and then halt it after some time, where does it hang (on which address?)? Could you perhaps get a screenshot of this situation?

Have you had your schematics and layout reviewed? If not, I suggest that you create a regular support case, making sure to upload schematics and Gerber (or Altium) files so that we can verify that the hardware is ok.

[Cyril Hruscak]

sd_softdevice_enable does not return at all (app_error_handler is not reached). It stays in loop waiting for EVENTS_LFCLKSTARTED as seen in disassembly window (see attachement). It never gets outside of the loop.

Best Regards, Cyril.

[Cyril Hruscak]

We're using 32MHz crystal oscillator for HFCLK. Is it eventually necessary to tell the softdevice that 32MHz crystal is used? If yes, how can it be done? I did not find any function for this in the API.

[Ole Morten]

There is a PAN on using a 32 MHz crystal with the first revision chip, so you should make sure to apply the workaround from the PAN document: https://www.nordicsemi.com/eng/content/download/29490/494569/file/nRF51822-PAN%20v2.0.pdf

However, I don't think this is the problem you're seeing here. Which version of S110 are you working with? It seems that you're using SDK 5.1.0 or similar, and this is only compatible with S110 version 6.0.0.

Also, have you tried running your project with command-line gdb? I've sometimes seen strange issues stemming from Eclipse's debugger startup-behavior.

[Cyril Hruscak]

We've used S110 version 5.2.1 which made the problems. After switching to version 6.0.0 it works. Thank you.