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Arduino not communicating with CR95HF properly Answered

I'm building an NFC reader/writer with Arduino Uno, Arduino click board and RFid click on ( http://www.mikroe.com/click/rfid/ ).
The click on board has a microcontroller called CR95HF ( http://www.st.com/st-web-ui/static/active/en/resource/technical/document/datasheet/DM00025644.pdf ). 

In order to make this work, i have to communicate through SPI. But I got the feeling it's not properly done. 
I keep sending data in the way I believe is right (because all found examples do it this way and the datasheet says so), 
yet I keep getting either 0 or 255 (when I move or touch the board). 
Mostly I've tried to send and receive the ECHO, but nothing seems to work. 

I'm starting to run out of ideas. If anyone please would like to help, it would be greatly appreciated. 
(my code is included in the attachment).

PS: this is an example that uses the same microcontroller on a different version of the RFid click board. 



3 years ago

I believe I understand the problem. It's the Arduino Uno Click Shield who creates short circuit.