52832 NFC change the serial number

[jwx]

i download the sample code (\examples\nfc\record_text) to pca10040,it can be detected by NFC reader,the serial number is 5f:46:ac:eb:75:a7:ea,if i want to change this number ,what can i do?

[endnode]

You probably mean ISO14443 7-byte UID (sometimes called Card Serial Number = CSN in RFID) which Nordic calls NFCID. Read more about it here. As you see it's about setting NFCIDSIZE part of SENSRES register and then and UID itself in NFCID1_LAST, NFCID1_2ND_LAST and NFCID1_3RD_LAST. It is populated by default from FICR NFC.TAGHEADERx registers.

(In other words I don't see any API function call to manage this so I'd write to NFCID1_xxx after NFC library is initialized.)

[CurtisHx]

Looks like nfc_t4t_setup loads the values from the FICR into the NFCID registers, but also caches it in RAM. Setting the NFCID registers after NFC library initialization does not appear to change the actual serial number.