How to set BLE device name based on device parameters

[StefXinet]

Dear Nordic,

we would like to set the BLE device name like this: "model" "serial number" (for example: "Model 024585").

The serial number is on a EEPROM, and the device name will have the same nave from the startup to the poweroff.

Following your example, the device name is a #define and sd_ble_gap_device_name_set() accepts only pointer to constant string, so please could you tell me how can I set a different device name based on custom serial number for each different device?

Thanks.

[Vidar Berg]

Hello,

You need to prepare the string into a contiguous buffer before you pass it to sd_ble_gap_device_name_set(). It may look something like this:

static void gap_params_init(void)
{
    uint32_t err_code;
    char device_name_str[BLE_GAP_DEVNAME_DEFAULT_LEN];
    char name[] = "Model";
    char sn[]   = "024585"; // Serial number to be loaded from an ext. EEPROM  
    
    sprintf(device_name_str, "%s %s", name, sn);

    err_code = sd_ble_gap_device_name_set(&sec_mode,
                                          (const uint8_t *) device_name_str,
                                          strlen(device_name_str));
    APP_ERROR_CHECK(err_code);
        
    ...    

Hope this helps. If anything is unclear, let me know.

Best regards,

Vidar

[StefXinet]

Thanks Vidar,

your solution is clear, but in this case you are passing to sd_ble_gap_device_name_set() a uint8_t* that isn't const

Ok for the typecasting, but could sd_ble_gap_device_name_set() accept a NON const pointer to string?

[Vidar Berg]

I left the typecast there because we use it in our examples, but it's not required.

[Randy Lee]

I'm using SDK 15.3 on a 52840 and this works on startup, no problem.

Now suppose I want to change the name every couple of minutes?  I can set the name with this code but it's not changing on the adverts as far as I can see.  Must be missing something.

This post ( How to change the device name?) says to issue a function call that doesn't exist in this version of SDK (the post is quite old) and I haven't figured out what the right one is in this version of SDK.  If I go back for an init using ble_advertising_init(), I get an 8 error code back.