No bluetooth advertisement is found

[danny0007]

Hi Community,

I made a custom board based on thingy53.

the custom board can be flashed with nRF5340-DK, I see the "merged_domains.hex" is flashed.

Also tried with nRF connect for desktop to flash the "dfu_application.zip", the result is the same.

the appliaction seems no problem, the output from the console looks same as on Thingy53:

*******************************************************************************

[00:00:00.005,187] <inf> Custom_MYMO: Starting Custom

[00:00:00.011,138] <inf> fs_nvs: 8 Sectors of 4096 bytes
[00:00:00.011,138] <inf> fs_nvs: alloc wra: 0, fd0
[00:00:00.011,138] <inf> fs_nvs: data wra: 0, 1c
[00:00:00.036,437] <inf> bt_hci_core: HW Platform: Nordic Semiconductor (0x0002)
[00:00:00.036,468] <inf> bt_hci_core: HW Variant: nRF53x (0x0003)
[00:00:00.036,468] <inf> bt_hci_core: Firmware: Standard Bluetooth controller (0x00) Version 54.58864 Build 1214809870
[00:00:00.038,757] <inf> bt_hci_core: No ID address. App must call settings_load()
[00:00:00.041,198] <inf> bt_hci_core: Identity: E6:0B:3C:01:47:D0 (random)
[00:00:00.041,229] <inf> bt_hci_core: HCI: version 5.4 (0x0d) revision 0x218f, manufacturer 0x0059
[00:00:00.041,259] <inf> bt_hci_core: LMP: version 5.4 (0x0d) subver 0x218f
return of bt_services_init:0
[00:00:00.044,982] <inf> Custom_MYMO: test print---0

[00:00:00.044,982] <inf> Custom_MYMO: Bluetooth initialized

[00:00:00.044,982] <inf> Custom_MYMO: test print---1

[00:00:00.050,628] <inf> Custom_MYMO: test print---2

[00:00:00.050,628] <inf> Custom_MYMO: Advertising successfully started

MCUBOOT_IMAGE_VERSION:0.0.3
switch LED
switch LED
switch LED
switch LED
switch LED

**************************************************************************************

As you can see "Advertising successfully started" , that means no issue for this function in main:

err = bt_le_adv_start(BT_LE_ADV_CONN, ad, ARRAY_SIZE(ad), sd, ARRAY_SIZE(sd));

    if (err) {

        LOG_ERR("Advertising failed to start (err %d)\n", err);

        return err;

    }

the problem is I can not find the bluetooth advertisement with mobile phone. how can I verify if the network core works correctly? or any other idea?

Best regards

Danny 

[ketiljo]

What's the specification for the 32 MHz crystal you're uisng? Espesially the CL value is important. The default value for the internal load caps is set for a crystal with CL = 8pF and you need to adjust this if you're using a different crystal. Else the frequency of the carrier will be out of spec. 

[danny0007]

this is the 32MHz I'm using: ndk_08142018_NX2016SA-32M-EXS00A-CS06465_SS-1389053.pdf

according to the datasheet, CL=10pF. 

this is the 32.768KHz c_NX2012SA_STD_MUB_1_e-1317508.pdf CL=12.5pF

shall I change them to other crystals? 

[Einar Thorsrud]

Hi,

It is difficult to read the value right of the XOSC32MCAPS registet (0x400045c4) as the calculation includes calibration values that vary from chip to chip, but the key was that if you see this change when you use different CONFIG_SOC_HFXO_CAP_INT_VALUE_X2 values you know you are setting it.

You could try to remove C20 and C30 and replace L6 with a 0 ohm resistor and see if that improves things? Other than that, I would recomend that you submit your design for a review.

PS: Even if the truning is bad, you would normally get something radatd, so that if you place a sniffer or a phone or similar right next to the device, you I would expect you should se something as long as it is advertising.

[danny0007]

Hi Einar,

our schematic is uploaded here: Nordic DevZone please check it out. Many thanks.

[Einar Thorsrud]

Hi,

Please upload the layout as gerber files in the private case as well so that we get a better understanding of your hardware.

[danny0007]

Hi Einar,

gerber file is uploaded.

[Einar Thorsrud]

Hi,

Thank you. We have looked at your design and are giving some feedback on that in the private ticket.

Regarding the issue of no advertising,  given that all looks good in the log and advertising is started, I susepct issues with the HFXO. Could it be that it is not properly starting or is oscillatign with wrong frequency?

If you have a spectrum analyzer, you can use the radio test sample and set up a constant carrier. Is the carrier located in the correct channel/frequency?. If you do not have a spectrum analyzer, you can also use the nRF Connect for Dekstop RSSI viewer app to see which channel there is traffic. The outcome of this test woul be if we see any radio TX at all, and if so, if we see it at the right frequency.

If there is no radio Tx acticity, perhaps you can measure on the crystal with an oscilliscope when doing advertising or similar? That will affect the crystal making the frequency off, but we can see if the XO is starting or not.