2 Replies Latest reply on Apr 6, 2011 10:20 AM by udayanu_

    I2C Wake feature on ES3 is not working

      Hi, I am having trouble testing the I2C Wake feature using an ES3 CY8C3866.  The basic read and write slave functionality works fine but it does not wake up.  I cannot figure out if I am missing anything.  Can anyone help?  I am listing the hardware setup and source for a basic I2C Slave.  Thanks.




      The hardware is setup as follows:


      Mode: Slave
      Data Rate: 100 kps
      Implementation: Fixed Function
      Address Decode: Hardware
      Slave Address: 0x3F
      Pin Connections: I2C0
      Enable wakeup from Sleep Mode: Yes.


      Pin settings:
      Input: Bidirectional, OpenDrain Low, Input Buffer Enabled, Input Synchronized
      Output: Fast, Vddio, 4mA source/ 8mA sink, Output Synchronized








      #include <device.h>


      uint8 I2CReadBuffer[128];
      uint8 I2CWriteBuffer[128];
      uint8 cloopCount;


      void main()
          /* Place your initialization/startup code here (e.g. MyInst_Start()) */


          I2C_SlaveInitWriteBuf( &I2CWriteBuffer, 128);
          I2C_SlaveInitReadBuf( &I2CReadBuffer, 128 );


          CYGlobalIntEnable; /* Uncomment this line to enable global interrupts.*/ 


              if ( I2C_SlaveStatus() & I2C_SSTAT_WR_CMPT )
                  for ( cloopCount = 0; cloopCount < I2C_SlaveGetWriteBufSize(); cloopCount++ )
                      I2CReadBuffer[cloopCount] = I2CWriteBuffer[cloopCount];


              if ( I2C_SlaveStatus() & I2C_SSTAT_RD_CMPT )
              if ( I2CWriteBuffer[0] == 0x24 )
                  CyPmSleep(PM_SLEEP_TIME_NONE, PM_SLEEP_SRC_I2C);
                  I2CWriteBuffer[0] == 0;

        • 1. Re: I2C Wake feature on ES3 is not working

           Nvm, I found the problem.  It was my mistake.  With the following.  Thanks anyway.


              "I2CWriteBuffer[0] == 0;"

          • 2. Re: I2C Wake feature on ES3 is not working

            Things to be made sure to use I2C Sleep wake up on PSoC3,

            • The I2C pin used should be either I2C0 or I2C1. I2C0 is the pair, and I2C1 is the pair.
            • The Wakeup on address match parameter should be enabled.
            • I2C should be set as the source of wake up before entering sleep.
            • In addition to this, the I2C component should be prepared for sleep mode operation before the devcie is put to sleep, the same can be done using the API, "I2C_Sleep()". After device comes out of sleep, the component active mode configuration has to be restored using the API, "I2C_RestoreConfig()".

            Note: I2C Sleep Wakeup functionality is available only on PSoC2 ES3 revision and later.