How to write data to Mifare DESFire EV2 NV memory?

[yu_vincentcy]

Hello,

I am developing an NFC reader using S32K144 and NFC3321 developement board. I got  "aNfcRdLib_SDK_Evaluation_v2.33" and imported "aNfc_S32K144_MIFAREDESFire_EVx". It is fine to run sample code (This sample code will read NFC first and write data back to card). But I found that when I put the same Mifare EV2 card in again, the previously written data would be reset to zero. What parameters should I change or what file should I use to write non-volatile information to the DESFire EV2 card?

[KaiLi]

Hello @yu_vincentcy 

Please check the routine "aNfc_S32K144_MIFAREDESFire_EVx". There should be formatting behavior in this. If you are only reading the card, you need to make some modification.

[yu_vincentcy]

Hello KaiLi

I am developing a digital key with NFC3321 and Mefire Desfire card.
1. I need to write some encrypted data to NFC card.
2. Use S32k144 as controller to read NFC data throuth NFC3321.

I did see a similar action to format the Application in the program example of "aNfcRdLib_SDK_Evaluation_v2.33", and I skipped these step (phalMfdfEVx_Format , phalMfdfEVx_CreateApplication) when I executed the example for the second time, but an error occurred when executing "phalMfdfEVx_SelectApplication". Which document I can referance to understand the flow of reading/writing data from DESfire card and function description of "aNfcRdLib_SDK_Evaluation_v2.33" library.

[KaiLi]

Hello @yu_vincentcy 

For MIFARE DESFire EVx development, you need to refer to the following documents at least:
1. AN12757 MIFARE DESFire EV3 features and hints
2. MF3D(H)x3 MIFARE DESFire EV3 contactless smartcard IC
But they are security files, which are available for you under NDA, if you have an NDA, please send email to [email protected] to apply for access rights of the two documents.