esb with softdevice - clock initialization failes (urgent)

RE: esb with softdevice - clock initialization failes (urgent)

ovrebekk — Fri, 30 Oct 2020 07:47:54 GMT

That is excellent news Michał, I will close the case then 🙂

RE: esb with softdevice - clock initialization failes (urgent)

Michal — Thu, 29 Oct 2020 11:59:42 GMT

Hi,

Turns out I changed something in nrf_esb.c when testing in the beginning and that change only affected RX part. After reverting all changes in nrf_esb.c everything works smooth. So after all looks like only change I needed was to make an offset in linker for those 8 bytes used by softdevice.

Thank you all for the support!

Best regards,
Michał

RE: esb with softdevice - clock initialization failes (urgent)

Krzysztof Chruscinski — Thu, 29 Oct 2020 07:37:11 GMT

Could it be some stack size? As now interrupt goes through mbr and softdevice a bit more stack is needed.

RE: esb with softdevice - clock initialization failes (urgent)

Michal — Wed, 28 Oct 2020 15:12:45 GMT

Hi Torbjørn,

I am calling __WFE() in main loop but the code seems to enter hardfault even if I remove that. Also I don't configure RAM retention in my application, I don't know if it is enabled by default?

Code goes to A60 and then enters Hardfault from ses_startup_nrf52840.s.

Best regards,
Michał

RE: esb with softdevice - clock initialization failes (urgent)

ovrebekk — Wed, 28 Oct 2020 12:17:30 GMT

Hi Michał

I assume you are using sleep modes occasionally?

If so, which ones?

Any chance you are disabling RAM retention in sleep to reduce current draw?

[quote user="biolu"]0x00000A60 is not mysterious anymore it is MBR's hardfault handler function address right?[/quote]

That is correct, but this should forward to the hardfault handler or app_error_handler of the application. Will the code execution not continue after reaching 0x00000A60?

Best regards
Torbjørn

RE: esb with softdevice - clock initialization failes (urgent)

Michal — Tue, 27 Oct 2020 23:08:03 GMT

Here is the s140 documentation - link . It says that with softdevice disable RAM consumption is 8bytes. Anything I am missing?

RE: esb with softdevice - clock initialization failes (urgent)

Nguyen Hoan Hoang — Tue, 27 Oct 2020 22:46:24 GMT

At a min, check in the softdevice doc for min ram required not just 80 or 160. It is much more than that with SD7. Secondly check the interrupt handler for ESB and any devices you are using. Make sure you have them hookup.

RE: esb with softdevice - clock initialization failes (urgent)

Michal — Tue, 27 Oct 2020 22:41:34 GMT

Minimum RAM required by Softdevice when it is not enabled is 8 bytes as mentioned in documentation linked by Torbjørn.

But I also thought that maybe more bytes are required and tried to move RAM start by 80 and 160 bytes. But that didn't help and I was still getting hardfault.

Do you have any suggestion on this?

RE: esb with softdevice - clock initialization failes (urgent)

Nguyen Hoan Hoang — Tue, 27 Oct 2020 22:29:39 GMT

8 bytes RAM are not sufficient. You need the reserve at least the minimum required by Softdevice. I have written a firmware using ESB and Softdevice only used for DFU just like yours.

RE: esb with softdevice - clock initialization failes (urgent)

Michal — Tue, 27 Oct 2020 19:49:18 GMT

Hi Torbjørn,

Actually it did help! I2C and spi initialized without a problem. But now after ESB init, code executes few more lines and then again jumps to that mysterious 0x00000A60 address and then I get HardFualt.

What else can be wrong here?

Best regards

EDIT:

0x00000A60 is not mysterious anymore it is MBR's hardfault handler function address right?

Also I can see that application runs for few more cycles before I get this hardfault. Just sharing an observation.

EDIT2:

I found out that my tx works fine ! I was testing only with rx so far. Unfortunately rx still crashes with hardfault without clear reason

RE: esb with softdevice - clock initialization failes (urgent)

ovrebekk — Tue, 27 Oct 2020 19:37:26 GMT

Hi Michał

A colleague of mine pointed out that when you have a SoftDevice added you actually have to reserve 8 bytes of RAM for the SoftDevice, even if you don't enable it.

This is mentioned in the documentation, here.

Could you try changing the RAM start address from 0x20000000 to 0x20000008 and see if it solves the issue?

Best regards
Torbjørn

RE: esb with softdevice - clock initialization failes (urgent)

Michal — Tue, 27 Oct 2020 18:48:45 GMT

Hi Krzysztof :)

thank you for the input but that doesn't fix the issue. I am actually testing this without btl right now, just sd + application (and I get the same behaviour in both cases) so I wasn't expecting this to help in my case.

Any other suggestions?

Thanks,
Michał B

RE: esb with softdevice - clock initialization failes (urgent)

Krzysztof Chruscinski — Tue, 27 Oct 2020 11:13:11 GMT

can you try to add following code at the beginning of your application

sd_softdevice_vector_table_base_set(CODE_START);

If you are jumping to the application from the bootloader, softdevice might not forward interrupts to the application.

RE: esb with softdevice - clock initialization failes (urgent)

Michal — Tue, 27 Oct 2020 10:00:29 GMT

Hi Torbjørn,

So I tried to access NRF_CLOCK registers directly as you suggested. I was observing CLOCK registers in SES ide and I can see that both clocks has status "running" so this seems to be fine.

Still there seems to be a problem when accessing i2c or spi - device bricks then. As those peripherals require hfclk I believe there is still something wrong with hfclk initialization.

I noticed while debugging that code goes to 0x00000A60 addres which I believe is softdevice? Does it make sense ? I am using s140 sd 7.0.1 for nrf52840

Thanks

RE: esb with softdevice - clock initialization failes (urgent)

ovrebekk — Tue, 27 Oct 2020 08:00:34 GMT

Hi Michał

Sorry, I didn't realize that the issue happens even when the SoftDevice is disabled. I will have to check internally if this is a known issue.

In the mean time, could you try to start the clocks by accessing the hardware registers directly and see if that works?

To start the LF clock just run the following code:

NRF_CLOCK->EVENTS_LFCLKSTARTED = 0;
NRF_CLOCK->TASKS_LFCLKSTART = 1;
while(NRF_CLOCK->EVENTS_LFCLKSTARTED == 0);

You can also do something similar for the HF clock, just replace LF with HF in the code snippet above.

Best regards
Torbjørn

RE: esb with softdevice - clock initialization failes (urgent)

Michal — Mon, 26 Oct 2020 16:55:19 GMT

Hi Torbjørn,

Yes, I can not enable the SoftDevice in my main application. This is actually what I am trying to do.

But as mentioned in first post - if I just put softdevice in flash and not enable it, the application crashes on clock request. How should I request hfclk when softdevice is present in flash but not enabled in software?

Thanks

RE: esb with softdevice - clock initialization failes (urgent)

ovrebekk — Mon, 26 Oct 2020 16:34:04 GMT

Hi Michał

My apologies, it is true that accessing the RADIO peripheral directly when the SoftDevice is enabled is not possible. I should have realized this when reading your original question.

As you can read here many peripherals are either blocked or restricted when the SoftDevice is enabled. Blocked peripherals can not be accessed at all, while restricted peripherals can be accessed only if you use the SoftDevice API's.

The only way to use the ESB library while the SoftDevice is enabled is to run all ESB activity inside a SoftDevice timeslot, which adds quite a lot of complexity to the application.

Is there a way you can modify your application to not enable the SoftDevice when running ESB?

Best regards
Torbjørn

RE: esb with softdevice - clock initialization failes (urgent)

Michal — Mon, 26 Oct 2020 13:44:21 GMT

Hi Torbjørn,

I am a bit confused: I don't want to use softdevice in my main application so I am not enabling softdevice at all. Shouldn't in that case "standard" nrfx_clock api be fine as suggested by Nguyen? I tried that but it doesn't work for me.

I tried to add softdevice to my application by using softdevice handler module, because I also need flash access. Then I am only requesting hfclk and that works fine. Unfortunately when initializing ESB protocol, exactly when accesing first RADIO register (which is TXPOWER but I don't this matters) application hangs. Is using ESB with softdevice enabled a valid use case? I guess all RADIO registers should be accessed via SD api when it is enabled but there no such ESB implementation which uses SD api.

Best regards

RE: esb with softdevice - clock initialization failes (urgent)

ovrebekk — Mon, 26 Oct 2020 08:39:28 GMT

Hi Michał

When using the SoftDevice you shouldn't access the clock peripheral directly, which is what the nrfx_clock driver is doing.

Starting LF clock is not necessary, since the SoftDevice starts this automatically, but if you want to change the LF clock source you have to do this as a part of the SoftDevice initialization.

Starting the external HF clock can be done by calling sd_clock_hfclk_request(), after you have enabled the SoftDevice.

Best regards
Torbjørn

RE: esb with softdevice - clock initialization failes (urgent)

Nguyen Hoan Hoang — Mon, 26 Oct 2020 07:35:02 GMT

I removed that clocks_start() and only use nrfx_clock_hfclk_start() directly without the while and that works for me.