change IEEE MAC address of nrf51822

Question

If I bought unique MAC address from IEEE. How can I update to nrf51822?

Eric Stutzenberger · Accepted Answer

Hi Fiske and Jones, 
 This answer expands a bit on Einar's answer to give you an idea of what I do for our product. 
 In our factory, we program the MAC address we want to use to the UICR using our JLink script. This way it is only erased if the entire part is erased which shouldn't happen during production. If you want to use a Public Static Address, then you need to buy a block of MAC addresses from IEEE. 
 Next, what we do is during boot, I check the UICR to see if it contains a MAC address (essentially, check that it is not FFFFFFFFFFFF or 000000000000. I read the data out of that UICR into the ble_gap_addr_t structure and then set it as a BLE_GAP_ADDR_TYPE_PUBLIC. Here is a code snippet: 
 /* Get the stored MAC address, little-endian (LSB first). Returns
 true if it came from the UICR, or false if it came from the
 FICR. */
bool get_mac_le(uint8_t *buf)
{
 bool uicr = true;
 const uint8_t *mac = MAC_UICR_ADDR;

 if (all_equal(mac, 0x00, 6) || all_equal(mac, 0xff, 6))
 {
 mac = (const uint8_t *)&(NRF_FICR->DEVICEADDR[0]);
 uicr = false;
 }
 memcpy(buf, mac, 6);

 /* If we pulled a random address from the FICR, the top
 two bits must be 11 per BT spec */
 if (uicr == false)
 buf[5] |= 0xc0;

 return uicr;
}
 
 Then I do the following elsewhere when booting up: 
 //set the mac
 ble_gap_addr_t addr;
 
 if(get_mac_le(addr.addr))
 {
 addr.addr_type = BLE_GAP_ADDR_TYPE_PUBLIC;
 }
 else
 {
 addr.addr_type = BLE_GAP_ADDR_TYPE_RANDOM_STATIC;
 }
 err_code = sd_ble_gap_address_set(BLE_GAP_ADDR_CYCLE_MODE_NONE, &addr);
 APP_ERROR_CHECK(err_code);
 
 Note that as I said earlier, this method is not protected from having the MAC address erased. There is no way to safely store a MAC on the nRF51. Our programming script reads out this location to see if there is a current MAC and writes it back later if there is one. 
 Hope this helps, 
 Eric

change IEEE MAC address of nrf51822

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