topic CLRC663 T0 underflow and T0COUNTERVAL register does not keep values in NFC

CLRC663 T0 underflow and T0COUNTERVAL register does not keep values

M_Chene — Tue, 17 Aug 2021 16:36:33 GMT

Hello everybody,

I am working on a project in which I use a CLRC663 for NFC communication with type 2 tags. I use this library that I adapted for the RS232 communication protocol ( I just defined write_reg and read_reg functions) : https://github.com/kenny5660/CLRC663

When I try to read/ write registers as Version register or command register all works as it should. However, when I try to send the REQA protocole, I have T0 underflow IRQ and when I try to change the value in T0COUNTERVAL[HI/LO] registers nothing change and the CLRC answer me that the 2 registers are at 0x00 when I read them.

As initialisation I use CLRC663_AN1102_recommended_registers(CLRC663_PROTO_ISO14443A_106_MILLER_MANCHESTER); function and I do my REQA after.

Do you have some ideas to help me with this problem ?

Thanks in advance

Mathieu

Re: CLRC663 T0 underflow and T0COUNTERVAL register does not keep values

fangfang — Wed, 18 Aug 2021 02:20:35 GMT

Hello,

One may refer to the code as the link.

URL:https://community.nxp.com/t5/NFC-Knowledge-Base/how-to-communicate-between-LPC1769-and-RC663-via-SPI-based-on/ta-p/1303617.

It is SPI communication .But the application can meet your requirement.

Have a nice day.

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Re: CLRC663 T0 underflow and T0COUNTERVAL register does not keep values

lcenni — Tue, 02 Aug 2022 15:46:09 GMT

Hi,

I am developing a similar product on a microcontroller different from NXP, and the whole library is very hard to integrate and very poorly documented

Would you like to get in touch?

Write me at cgaudiolaboratories.cg2@gmail.com

Bye