6 Replies Latest reply on May 2, 2017 7:40 AM by e.pratt_1639216

    Problem with SPI Master communication between PSOC BLE and External devices (Pi and LM74)?

    user_504416177

      Hi Every one,

         

      I am back once again with my stupid questions :p.

         

      But, I am very thankful to you all for your quick help.

         

      This time I have the following problem : May be there is a problem in understanding the thing, but your suggestions are highly needed.

         

      I am using PSOC 4 Ble chip, Temperature sensor (LM74) and Raspberry Pi.

         

      1. I want to read data from LM74 via PSOC 4 BLE and Pi.

         

      2. I also like to get data (from other sensor) via SPI from PSOC to Pi.

         

      But, LM74 can only act as 3-wire SPI salve: this means Pi and PSOC will act as SPI master (bidirectional).

         

      Since i have limited resources in PSOC 4 BLE I cannot use both spi master and slave blocks in one project design: I thought the following way:

         

      Pi will be the master for both PSOC and LM74 and will operate in daisy chain.

         

      PSOC will act as master for LM74 and slave for Pi, this means PSOC spi master will have two chip select line(controlled via control register).

         

      Now the question is: Is it possible for 3 wire PSOC SPI master to act as master for LM74 and slave for Raspberry PI?

         

      Looking forward for your suggestions

         

      Regards

         

      maknight