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VCecc.1
Associate
May 4, 2020
Solved

Hi, I'm using ST25DV04K. I'm trying to write 16 Bytes in System Configuration Area, but after two Bytes of the stream I get a NACK from the device. Instead, if I write two Bytes at a time, it works and I can write everything... Suggestions?

  • May 4, 2020
  • 4 replies
  • 1014 views

..

    This topic has been closed for replies.
    Best answer by Rene Lenerve

    Hi @VCecc.1​ ,

    Sorry I was wrong, I've read more carefully the datasheet of the ST25DV (https://www.st.com/content/st_com/en/products/nfc/st25-nfc-rfid-tags-readers/st25-dynamic-nfc-tags/st25dv-i2c-series-dynamic-nfc-tags/st25dv04k.html) and it is mentioned that registers can be read continuously but same behavior is not available for the write command (chap 4.3 p 17).

    Hope this help you.

    Regards.

    4 replies

    Rene Lenerve
    ST Employee
    May 4, 2020

    Hi @VCecc.1​ ,

    This is strange, you should be able to write the 16 bytes in one command. I'm guessing that you are writing at address 0000h in the system area, so all 16 registers are accessible in write.

    Do you have same problem writing in the user area?

    Best Regards.

    VCecc.1
    VCecc.1Author
    Associate
    May 4, 2020

    Hi Rene,

    Yes, I set 0000h as start address then try to write 16 Bytes (from 0000h to 000Fh). It does not work. Session is open, in factif I write one byte at a time, I can customize/modify all 16 Bytes of Sys Config Area. If I try to do the same thing in User Area (same adresses but E2 bit = 0), it works, I write and read what I wrote.

    Best Regards

    Rene Lenerve
    Rene LenerveBest answer
    ST Employee
    May 4, 2020

    Hi @VCecc.1​ ,

    Sorry I was wrong, I've read more carefully the datasheet of the ST25DV (https://www.st.com/content/st_com/en/products/nfc/st25-nfc-rfid-tags-readers/st25-dynamic-nfc-tags/st25dv-i2c-series-dynamic-nfc-tags/st25dv04k.html) and it is mentioned that registers can be read continuously but same behavior is not available for the write command (chap 4.3 p 17).

    Hope this help you.

    Regards.

    VCecc.1
    VCecc.1Author
    Associate
    May 4, 2020

    Hi,

    ok, I understand, thankyou for your precious info