Anyone here used the PIC32 peripheral library for I2C?  I'm having a=20
hard time with this, and can't find my ICD3 to help diagnose what's=20
happening.
I'm continuously reading data from a slave I2C device (PIC18F25K42=20
based), and the master (PIC32MX320F128H) crashes (reboots) regularly. =20
I'm posting about the maser here...

Flags on reboot only have the POR and BOR flags set.  Adding a bit of=20
bulk capacitance (10uf) does not help.  And this is happening with both=20
Pickit3 power or LiPo w/5V DC-DC power.  I also don't see a way to=20
change BOR threshold voltage as with other PIC series.
Logic analyzer says that it's happening at different points, but always=20
between I2C start and stop.

I'm at a loss as to what to test next, but perhaps someone can identify=20
something I'm doing wrong?  This is my master code to read data.  The=20
delays were put in earlier when testing w/o error-checking, and seems to=20
still help to reduce crashes.
HandleI2CErrors() is just a quick function to check and clear=20
arbitration, TX overflow, and RX overflow errors, and also sets an LED=20
to alert me, but that LED stays off.

signed int ReadAFEValue(void)
{
     signed int result, inVal, retVal;


     retVal =3D 1;

     if (PLIB_I2C_BusIsIdle(I2C_ID_1))
     {
         PLIB_I2C_MasterStart(I2C_ID_1);

         // Tell AFE to restart result counter and be ready to send data...
//        delay_us(100);
         DelayMs(1);
         if (PLIB_I2C_TransmitterIsReady(I2C_ID_1))
         {

             PLIB_I2C_TransmitterByteSend(I2C_ID_1,0x54);             //=20
Slave addr 0x2A in bits 7:1. 1 in LSB =3D read request, or 0 =3D write req.=
..
             if (PLIB_I2C_TransmitterByteWasAcknowledged(I2C_ID_1))
             {
//                delay_us(100);
                 DelayMs(1);
                 if (PLIB_I2C_TransmitterIsReady(I2C_ID_1))
                 {
                     PLIB_I2C_TransmitterByteSend(I2C_ID_1,0xB0);    =20
                 // Command for set mode to read_data mode
                     if (PLIB_I2C_TransmitterByteWasAcknowledged(I2C_ID_1))
                     {
                         HandleI2CErrors();

                         // Restart...
//                        delay_us(200);
                         DelayMs(1);
                         if (PLIB_I2C_BusIsIdle(I2C_ID_1))
                         {
                             PLIB_I2C_MasterStartRepeat(I2C_ID_1);

                             HandleI2CErrors();

                             // Tell AFE we want to read data now...
//                            delay_us(200);
                             DelayMs(1);
                             if (PLIB_I2C_TransmitterIsReady(I2C_ID_1))
                             {
PLIB_I2C_TransmitterByteSend(I2C_ID_1,0x55); // Slave addr 0x2A in bits=20
7:1. 1 in LSB =3D read request, or 0 =3D write req..
                                 if=20
(PLIB_I2C_TransmitterByteWasAcknowledged(I2C_ID_1))
                                 {
                                     HandleI2CErrors();

//                                    delay_us(200);
                                     DelayMs(1);
PLIB_I2C_MasterReceiverClock1Byte(I2C_ID_1); // Get first byte back from=20
AFE.

//                                    delay_us(100);
                                     DelayMs(1);
                                     if=20
(PLIB_I2C_ReceivedByteIsAvailable(I2C_ID_1))
                                     {
                                         if=20
(PLIB_I2C_MasterReceiverReadyToAcknowledge(I2C_ID_1))
                                         {
                                             result =3D=20
PLIB_I2C_ReceivedByteGet(I2C_ID_1);                // TODO -- store this=20
somewhere
PLIB_I2C_ReceivedByteAcknowledge(I2C_ID_1, true);
                                 //            while=20
(!PLIB_I2C_ReceiverByteAcknowledgeHasCompleted(I2C_ID_1));
                                         }
                                     }

                                     HandleI2CErrors();

//                                    delay_us(200);
                                     DelayMs(1);
PLIB_I2C_MasterReceiverClock1Byte(I2C_ID_1); // Get second byte back=20
from AFE.

//                                    delay_us(200);
                                     DelayMs(1);
                                     if=20
(PLIB_I2C_ReceivedByteIsAvailable(I2C_ID_1))
                                     {
                                         if=20
(PLIB_I2C_MasterReceiverReadyToAcknowledge(I2C_ID_1))
                                         {
                                             inVal =3D=20
PLIB_I2C_ReceivedByteGet(I2C_ID_1);                    // TODO -- store=20
this somewhere
PLIB_I2C_ReceivedByteAcknowledge(I2C_ID_1, false);            // NAK=20
here is required for last byte
                                             result  =3D result | (inVal=20
<< 8);
                                             retVal =3D result;
                                         }
                                     }

                                     HandleI2CErrors();

                                 //    DelayMs(1);
//                                    delay_us(200);
                                     DelayMs(1);
                                     while=20
(PLIB_I2C_TransmitterIsReady(I2C_ID_1) =3D=3D 0);                    // TOD=
O=20
-- countdown and timeout here?
                                 }
                                 else
                                     retVal =3D -8;
                             }
                             else
                                 retVal =3D -7;
                         }
                         else
                             retVal =3D -6;
                     }
                     else
                         retVal =3D -5;
                 }
                 else
                     retVal =3D -4;
             }
             else
                 retVal =3D -3;
         }
         else
             retVal =3D -2;

         PLIB_I2C_MasterStop(I2C_ID_1);
     }

     return retVal;
}        // ReadAFEValue()



Cheers,
-Neil



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