2020-05-20 01:00 AM
Hello ST community
We are making a customized PCB as an RF front end based on ST25U3993 (but without carrier cancellation circuit and log ampifier). We would use the eval kit with the ST GUI for tag reading. . My question is
1.) I would connect SPI interface (CLK, MISO, MOSI) and 93-signal(EN, IRQ, NSC) of our external RFID chip to the jumpers L and M (J10, J12) on the eval board. How do i disable the on-board RFID chip ?
2.) Since there is no carrier cancellation on our PCB and SPI interface on the eval board is a part of it (MOSi, CLK, ETC), do we need to do some changes other than disabling the on-board RFID chip.
Best and thanks for the support
LK
2020-05-27 01:09 AM
Hello
Alternatively,
1.) do i need to keep NCS pin of the board RFID chip (on the eval board) high to disable it's SPI ?
2.) I think sharing two RFID chips on the same SPI and controlled by the eval board- microcontroller should also be possible but this would require changing the FW of the uC.
3.) A similar approach https://community.st.com/s/question/0D50X0000CBlGLuSQN/how-to-port-the-st25ru3993-firmware-to-a-stand-alone-mcu-board uses a different uC by disconnecting R7-R13 and putting the on-board uC in low power mode. Would it be possible to put on board RFID chip to low power or shutdown ?
I am a hardware engineer and best would be to to use the same FW and Eval GUI. What is the recommend way to verify customer design board for such cross-connections. We need to know this to decide the next steps on this project.
Thanks for the support
LK