specific unique id for device detection

[capricorn]

Hi

I am looking for unique id of nrf52. is there any to set or generate unique id throughout all nrf52 devices.

Thanks & Regards Paramvir Singh

[Sigurd]

Hi,

You have the DEVICEID registers in FICR(Factory information configuration registers). The 2 DEVICEID registers each contain a 64 bit unique device identifier.

If you want to read and print the DEVICEID in the FICR register, you can do it like this:

NRF_LOG_INFO("DEVICEID0: %08X\n", NRF_FICR->DEVICEID[0]);
NRF_LOG_INFO("DEVICEID1: %08X\n", NRF_FICR->DEVICEID[1]);

[butch]

The FICR contains one.

// But only use LSB six bytes
define MAX_DEVICE_ID   0xfFfFfFfFfFfF

// FUTURE use a 48-bit bit field


DeviceID myID() {
/*
 * NRF_FICR->DEVICEADDR[] is array of 32-bit words.
 * NRF_FICR->DEVICEADDR yields type (unit32_t*)
 * Cast: (uint64_t*) NRF_FICR->DEVICEADDR yields type (unit64_t*)
 * Dereferencing: *(uint64_t*) NRF_FICR->DEVICEADDR yields type uint64_t
 *
 * Nordic doc asserts upper two bytes read all ones.
 */
uint64_t result = *((uint64_t*) NRF_FICR->DEVICEADDR);

// Mask off upper bytes, to match over-the-air length of 6 bytes.
result = result & MAX_DEVICE_ID;

assert(result <= MAX_DEVICE_ID);
return result;
}

[erltot]

Is there any relation towards the MAC address you see when you use BLE ? Can you also use that as a unique identifer?

[Sigurd]

Hi Erlot,

The DEVICEADDR registers are used for that(48 bit device address). See this answer on how the MAC address is derived from the DEVICEADDR .

[erltot]

What is the difference between upper and lower case letters in

define MAX_DEVICE_ID 0xfFfFfFfFfFfF

?