1 Reply Latest reply on Jul 7, 2017 2:57 AM by user_1377889

    SPI Glitch when going to deepsleep

    jyu_2228016

      Hey i'm on the CYBLE-224110-00 with SPI pins set to

         

      MISO = P2.1

         

      MOSI = P3.1

         

      SCLK = P3.4

         

      SS_BLK = P3.5

         

      And I attach a pic of my pin cofiguration of SS_BLK and SCLK.

         

      So what happens is that I put the device to deepsleep and I see a ~180 uSec glitch (starts at Vdd, down to Vss, back to Vdd) whenever I wake up from a timer wake up interrupt. I see this glitch on P3.4 and P3.5 but not P2.1 or P3.1. I don't know if the glitch is occurring on other pins, I have not sampled the other pins yet. ( I tried to manually write(1) to the SS_BLK and SCLK pins right before I sleep but it didn't help solve the glitch. 

         

      Anyone have an idea what the hell I'm seeing?

         

      I have a work around right now by putting the device to sleep instead of deepsleep. This seems to solve the glitch I'm seeing.

         

      Sleep code:

         

      SPI_ACCX_Sleep();
              UART_DEB_Sleep(); 

         

      CySysPmDeepSleep();
              SPI_ACCX_Wakeup();
              UART_DEB_Wakeup();