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Visitor II
June 29, 2022
Solved

ST25RU3993-HPEV Read_Gen2 command

  • June 29, 2022
  • 1 reply
  • 785 views

While trying to read gen2 tags with the ST25RU3993 reader. Reading address 0x02 in the EPC memory bank seem to work, but word addresses beyond 0x7F in the User bank give me an error (ERR_RXCOUNT). I know that the memory is accessible with another reader in my lab, so it should work with this reader. The tag is based on the EM4325 chip and I'm trying to access system memory located at 0xEC and beyond, the datasheet says these pages have no read protection.

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    Best answer by Nick K

    Hello NRowa.1,

    I checked and tried to read system memory from a EM4325 transponder and have no issue with reading word addresses above 0xEC when using the ST25RU3993 SDK. 

    The error ERR_RXCOUNT happens when the ST25RU3993 do not receive the expected number of bits from the transponder during the reply. Reason could be noise or some other disturbance. Also a not tuned antenna could be the reason. Please try to tuned the antenna before accessing the transponder. As a reference you could find in the STUHFL_demo a code snippet to run tuning.

    BR 

    1 reply

    Nick KAnswer
    ST Employee
    September 13, 2022

    Hello NRowa.1,

    I checked and tried to read system memory from a EM4325 transponder and have no issue with reading word addresses above 0xEC when using the ST25RU3993 SDK. 

    The error ERR_RXCOUNT happens when the ST25RU3993 do not receive the expected number of bits from the transponder during the reply. Reason could be noise or some other disturbance. Also a not tuned antenna could be the reason. Please try to tuned the antenna before accessing the transponder. As a reference you could find in the STUHFL_demo a code snippet to run tuning.

    BR