ST25R3918 I2C driver space-B access issue

[_AK]

Hello,

I am writing interface for ST25R3918 NFC chip for our BSPs using I2C protocol. The datasheet of the chip mentions non-standard I2C command for space-B access that there is no ACK from chip after sending of first byte "FBh".

I can see that ST provided driver handles this by special flag "I2C_FIRST_AND_NEXT_FRAME", but how would I handle it for non-STM32 external MCUs as this would generally throw error of NACK? Does that mean that this NFC chip will not work with non-STM32 MCUs using I2C protocol?

Thanks

[Brian TIDAL]

Hi,

here is an I2C trace of reading B-registers 30h, 31h, 32h and 33h:

 

And the related SCL and SDA lines:

The I2C interface is being used with non-ST MCU (e.g. R-Pi), so I am confident this will work with your MCU. 

Rgds

BT

[_AK]

Hi,
Thanks for the trace, I will test it. The trace you shared has ACK after the "FBh" byte sent, but not in the datasheet. Is it a mistake or something else I might be missing?

Thanks

[Brian TIDAL]

Hi, 

this is obviously a typo in the datasheet. I've just reported it internally. Thanks for reporting this issue.

Rgds

BT