X-NUCLEO-NFC03A1 Send Receive Command not detecting RFID tag

[ClosedBridge]

Hello,

I'm using the X-NUCLEO-NFC03A1 dev kit with the CR95HF RFID chip. The protocol to talk to the chip I'm using is SPI, and the ISO configured is 15693. I can confirm SPI comms are working as both the ID and ECHO commands work. I also seem to get the correct response from the chip with the protocol is selected and configured for 15693. Unfortunately it seems like RFID tags are not getting detected. 

I can confirm the RFID tags are programmed and work as expected as I can used my phone's RFID scanner to detect the tag, and the protocol is detected to be 15693. I've attached a Saleae capture of the SPI comms between the MCU and the CR95HF when using a Send/Receive command. The error code that is returned by the CR95HF is 0x87, which corresponds to not detecting an RFID tag.

Currently I'm using the default 15693 protocol config of 0x00, but have tried lowering the protocol bit rate and waiting for SOF.

Help would be greatly appreciated!

Capture of configuring the protocol

Capture of Send/Receive Command

[Brian TIDAL]

Hi,

the sendReceive command in the trace (0x04 0x00) contains an empty payload. Therefore the device only sends an isolated EOF. Thus no tag replies.

I would recommend to use the various libraries and demos provided on st.com web site rather that reimplementing the protocol.

Rgds

BT

[ClosedBridge]

Thanks for responding. Is the necessary payload described by the RFID tag manufacturer?

[Brian TIDAL]

Hi,

the various commands are described in datasheets of tag manufacturer based on mandatory commands from the ISO 15693 standard, optional commands from the ISO 15693 standard and proprietary/custom commands defined by the tag manufacturer.

I would suggest to use the X-CUBE-NFC3 package or the ST25 embedded NFC library package that provide supports for usual ISO 15693 commands for tag inventory and data exchange.

Rgds

BT