No device found with bt_le_scan_start and observer

[warcomeb-am]

Dear,

I am using nRF5340 and I am trying to scan devices around me. With the example observer my device founds other devices around me, but when I use the same configuration and the same functions into my project the device doesn't find anything. The code is the same, exactly the same but I can't see anything.

The prj.conf is

#Peripherals
CONFIG_GPIO=y
CONFIG_SPI=y

CONFIG_FLASH=y
CONFIG_FLASH_PAGE_LAYOUT=y
CONFIG_MPU_ALLOW_FLASH_WRITE=y

CONFIG_PRINTK=y


# Bootloader
CONFIG_BOOTLOADER_MCUBOOT=y

# Bluetooth configuration
CONFIG_BT=y
#CONFIG_BT_PERIPHERAL=y
#CONFIG_BT_DEVICE_NAME="Test"
#CONFIG_BT_DEBUG_LOG=y
#CONFIG_BT_CENTRAL=y
#CONFIG_BT_SCAN=y
CONFIG_BT_OBSERVER=y

# Other 
CONFIG_MAIN_STACK_SIZE=2048

CONFIG_LOG=y

And the code is:

#include <zephyr/bluetooth/bluetooth.h>
#include <zephyr/bluetooth/hci.h>


#if (APP_DEBUG_ON == 1)
#include <zephyr/sys/printk.h>
#endif

#define DEVICE_NAME CONFIG_BT_DEVICE_NAME
#define DEVICE_NAME_LEN (sizeof(DEVICE_NAME) - 1)

static void deviceFound (const bt_addr_le_t *addr, 
                         int8_t rssi, 
                         uint8_t type,
                         struct net_buf_simple *buf)
{
    char dev[BT_ADDR_LE_STR_LEN];

    // if (type == BT_GAP_ADV_TYPE_ADV_SCAN_IND)
    // {
        bt_addr_le_to_str(addr, dev, sizeof(dev));
        printk("[DEVICE]: %s, AD evt type %u, AD data len %u, RSSI %i\n",dev, type, buf->len, rssi);
    // }


}

void Bluetooth_init (void)
{
    int err = 0;

    err = bt_enable(NULL);
    if (err) 
    {
#if (APP_DEBUG_ON == 1)
        printk("ERROR: Bluetooth init failed (err %d)\n", err);
#endif
        goto bluetooth_init_error;
    }

#if (APP_DEBUG_ON == 1)
    printk("BLUETOOTH0: Bluetooth initialized\n");
#endif

	struct bt_le_scan_param scanParam = 
    {
        .type       = BT_LE_SCAN_TYPE_PASSIVE,
        .options    = BT_LE_SCAN_OPT_FILTER_DUPLICATE,
        .interval   = BT_GAP_SCAN_FAST_INTERVAL,
        .window     = BT_GAP_SCAN_FAST_WINDOW,
    };

    err = bt_le_scan_start(&scanParam, deviceFound);
    if (err) 
    {
#if (APP_DEBUG_ON == 1)
        printk("ERROR: Scanning failed to start (err %d)\n", err);
#endif
        goto bluetooth_init_error;
    }
#if (APP_DEBUG_ON == 1)
    printk("BLUETOOTH0: Scanning successfully started\n");
#endif

bluetooth_init_error:
    if (err)
    {
        // TODO
    }
}

The output log is:

BLUETOOTH0: Bluetooth initialized
BLUETOOTH0: Scanning successfully started

Where is it the error? Haw can I debug this issue?

Thanks

Marco

[Simonr]

Hi Marco

Can you try enabling CONFIG_BT_HCI=y as well in your config file. I'm not quite sure why you're not able to scan as expected with this implementation, might be because I'm missing insight, but your code builds fine in hello_world on our end. What Bluetooth controller are you using on the NET core? The Zephyr BLE controller or Nordic's SoftDevice controller?

Best regards,

Simon

[warcomeb-am]

Hi Simon,

I added the row into the config file. I put the start scan a little bit earlier than before and now somethings came up as you can see in the image (the black side is the app core, the white side is the network core)... but after some seconds no more can be found... nothing.

Just to be sure of this behaviour I switched off some beacons,  start the scan, and now switch on the beacons.. and it doesn't show these devices.  

I am sure that the app core is not blocked in a while loop or in a fail, because it does other things!

Best regards

Marco

[Hieu]

Hi Marco,

Simon is out of office and I will substitute for him here.

From your description and your log, does the scan stop working after mere five seconds?

To ensure the net core is also working, could you also setup another BLE activities running in parallel with scanning and get the log? Perhaps the easiest is a beacon broadcasting without a timeout.

Best regards,

Hieu

[warcomeb-am]

Hi Hieu,

nice to meet you. 

Yes, the scan stops working after mere five seconds.

For the test: can you suggest me the code to add this functionality?

Thanks

Marco

[Hieu]

Hi Marco,

Nice to meet you too!

Sorry for the late follow up. We are having a holiday staffing situation.

You could start advertising concurrently without timeout. The Scan & Advertise Sample shows you how to do it.

Hieu

[warcomeb-am]

Hi Hieu,

by enabling the advertising concurrently without timeout the scanning works without problems as you can see in the image.

What can I do?

Thanks

Marco

[Hieu]

Hi Marco,

This is too strange.

Unfortunately, I am accessing my DKs remotely and I didn't set a nRF5340 DK up. I will try to reproduce and debug this when I get back to office next week. I will follow up latest by the end of Wednesday Jan 4. Sorry if that seems a bit long. We are a bit understaffed because of the holidays.

Hieu

[Hieu]

P.s: Are you enabling debug options in your build? If so, can you try the scan-only setup again without debug options? And if that works, can you try again with debug options but on NCS v2.0.2?

[Hieu]

Hi Marco,

I tried on my nRF5340 DK and I cannot reproduce your issue where the device hangs after 5 seconds.

Could you please retry what you are doing on a fresh Hello World project? If possible, add each piece of code one at a time, with a quick test to see if it is behaving as you expected.

Attached below is my test project which I tested in NCS v2.2.0 with debug options. You can find that I am using pretty much the same code you provided here, and it works normaly. If you try it, when build, please remember to include "add_scan.conf" and "nrf5340.conf."

hello_world_add_scan.zip

Hieu

[warcomeb-am]

Hi Hieu,

sorry for the delay, but I was out-of-office for holiday.

Your code work without any problem. I tried a new fresh project... but not works! Same code, it is only a new project! It is unbelivable for me!

Marco

[Hieu]

Hi Marco,

The fact that my project works on your end suggests that at least the problem is somewhere in the project setup, so it might be a good sign.

Could you run a diff/compare of the projects, see what the differences are? Remember to exclude the build folder.

Hieu

[warcomeb-am]

Hi Hieu,

it is very strange... there are no differences between the two project!

I am going crazy with that!

Marco