NTAG Plus: Can read session reg, but not memory

[claushm]

Hi all

I'm trying to bring up my own board with a NT3H2111 NTAG Plus.

I can read the session registers, but nothing else.

I have attached two logic analyser snap shots. One is showing the session register access that is working and the other a read from block 0x04 from the memory. As you can see, the second slave address is not acknowledged and then the communication stops.

I have not written to any of the registers. But using the "Connected Tags Explorer" demo, I can read the memory and registers. I cannot find anything wrong anywhere.

Is there a simple thing I'm missing?

Kind regards, Claus

[Kan_Li]

Hi Claus Mortensen ,

Thanks for the information! Referring to Memory Loc.png, it looks like the delay is too short between the first stop condition and the second start condition. The data sheet recommends at least 50us, please refer to the following for details.

Hope that helps,

Have a great day,
Kan

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[claushm]

Hi Kan

I already did the delay in a earlier try and it did not make any difference. And the documentation is saying "when I2C_CLOCK_STR is set to 0". It looks like it is default set to 1, so I read it as being not relevant.

As you know the session register read works. I then put in that access before the read from the EEPROM and now it works. I then changed to to times the same read to block zero. The first read does not work, but the second one does. And the delay of 50us is not needed. It will work anyway. This test is done with 65 us delay in it.

I have made a new screen shot and I hope I managed to insert it below :-)

Do you have any idea why first access do not work, except it is a session register read?

Kind regards, Claus

[Kan_Li]

Hi Claus,

Thanks for the information! does this issue always happen like that? or just for the first time access? and is it possible to share a snapshot of the schematics for the NT3H2111?

Thanks for your patience!

Have a great day,
Kan

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