TMS320F280049: I2C Repeated Start Behavior / RM bit / Accurate RX Count

//###########################################################################
//
// FILE:    Example_2807xI2C_eeprom.c
//
// TITLE:   I2C EEPROM Example
//
//! \addtogroup cpu01_example_list
//! <h1>I2C EEPROM Example (i2c_eeprom)</h1>
//!
//! This program will write 1-14 words to EEPROM and read them back.
//! The data written and the EEPROM address written to are contained
//! in the message structure, I2cMsgOut1. The data read back will be
//! contained in the message structure I2cMsgIn1.
//!
//! \b External \b Connections \n
//! - This program requires an external I2C EEPROM connected to
//!   the I2C bus at address 0x50.
//!
//
//###########################################################################
// $TI Release: F2807x Support Library v3.10.00.00 $
// $Release Date: Tue May 26 17:19:45 IST 2020 $
// $Copyright:
// Copyright (C) 2014-2020 Texas Instruments Incorporated - http://www.ti.com/
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions
// are met:
//
//   Redistributions of source code must retain the above copyright
//   notice, this list of conditions and the following disclaimer.
//
//   Redistributions in binary form must reproduce the above copyright
//   notice, this list of conditions and the following disclaimer in the
//   documentation and/or other materials provided with the
//   distribution.
//
//   Neither the name of Texas Instruments Incorporated nor the names of
//   its contributors may be used to endorse or promote products derived
//   from this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
// $
//###########################################################################

//
// Included Files
//
#include "F28x_Project.h"


//
// Defines
//
#define I2C_SLAVE_ADDR        0x50
#define I2C_NUMBYTES          2
#define I2C_EEPROM_ADDRESS    0x0000
#define I2C_FIFO_LEVEL        16

#define I2C_SUCCESS                 0
#define I2C_BUS_BUSY_ERROR          999
#define I2C_STP_NOT_READY_ERROR     1
#define SLAVE_NOT_READY_ERROR       2

#define DEVICE_SYSCLK_FREQ          120000000//SYSCLK = 120 MHz

#define EEPROM_MAX_WRITE_CYCLE      5     //5ms

#define WRITE_DELAY_TIME            (((EEPROM_MAX_WRITE_CYCLE * DEVICE_SYSCLK_FREQ)/1000)-9)/5

#define DEVICE_DELAY_US(x) F28x_usDelay(x)



//
// Function Prototypes
//
void i2c_init_old(void);
void I2C_GPIO_confi(void);
void I2CA_Init(void);
Uint16 handleNACK(void);

Uint16 checkBusStatus(void);

Uint16 I2CA_WriteData(Uint16 SlaveAddress, Uint16 address, Uint16 *txbuffer, Uint16 NumOfBytes);
Uint16 I2CA_ReadData(uint16_t SlaveAddress, uint16_t address, uint16_t *txbuffer, uint16_t NumOfBytes);

Uint16 PassCount=0;
Uint16 FailCount=0;


__interrupt void i2c_int1a_isr(void);

void pass(void);
void fail(void);

Uint16 r;

Uint16 I2C_status = 9;

//
// Main
//


uint16_t TXdata[66];
uint16_t RXdata[256];

void main(void)
{


//
// Step 1. Initialize System Control:
// PLL, WatchDog, enable Peripheral Clocks
// This example function is found in the F2837xS_SysCtrl.c file.
//
    InitSysCtrl();

//
// Step 2. Initialize GPIO:
// This example function is found in the F2837xS_Gpio.c file and
// illustrates how to set the GPIO to it's default state.
//
    InitGpio();

//
// For this example, only init the pins for the SCI-A port.
// These functions are found in the F2837xS_Gpio.c file.

    //XCLKOUT = GPIO73
    GPIO_SetupPinMux(73, GPIO_MUX_CPU1, 3);


    EALLOW;
    ClkCfgRegs.CLKSRCCTL3.bit.XCLKOUTSEL = 0;
    ClkCfgRegs.XCLKOUTDIVSEL.bit.XCLKOUTDIV = 3;
    EDIS;



    I2C_GPIO_confi();
//      i2c_init_old();
//
// Step 3. Clear all __interrupts and initialize PIE vector table:
// Disable CPU __interrupts
//
    DINT;

//
// Initialize PIE control registers to their default state.
// The default state is all PIE __interrupts disabled and flags
// are cleared.
// This function is found in the F2837xS_PieCtrl.c file.
//
    InitPieCtrl();

//
// Disable CPU __interrupts and clear all CPU __interrupt flags:
//
    IER = 0x0000;
    IFR = 0x0000;

//
// Initialize the PIE vector table with pointers to the shell Interrupt
// Service Routines (ISR).
// This will populate the entire table, even if the __interrupt
// is not used in this example.  This is useful for debug purposes.
// The shell ISR routines are found in F2837xS_DefaultIsr.c.
// This function is found in F2837xS_PieVect.c.
//
    InitPieVectTable();

//
// Interrupts that are used in this example are re-mapped to
// ISR functions found within this file.
//
    EALLOW;    // This is needed to write to EALLOW protected registers
    PieVectTable.I2CA_INT = &i2c_int1a_isr;
    EDIS;      // This is needed to disable write to EALLOW protected registers

//
// Step 4. Initialize the Device Peripherals:
//
    I2CA_Init();

//
// Step 5. User specific code
//

//
// Clear Counters
//
    PassCount = 0;
    FailCount = 0;

//
// Enable __interrupts required for this example
//

//
// Enable I2C __interrupt 1 in the PIE: Group 8 __interrupt 1
//
    PieCtrlRegs.PIEIER8.bit.INTx1 = 1;      //Enabling I2C non-FIFO interrupt

//
// Enable CPU INT8 which is connected to PIE group 8
//
    IER |= M_INT8;
    EINT;

    ESTOP0;

    r = 2;
    while(r<=66)
    {

       TXdata[r] = 55;
       RXdata[r] = 0;
       r++;
    }

    I2C_status = I2CA_WriteData(I2C_SLAVE_ADDR+10, I2C_EEPROM_ADDRESS, TXdata, 4);
    DEVICE_DELAY_US(2*WRITE_DELAY_TIME); //wait for 5ms for max write time for EEPROM i'm using
    I2C_status = I2CA_ReadData(I2C_SLAVE_ADDR+30, I2C_EEPROM_ADDRESS, RXdata, 4);

    ESTOP0;

    r = 0;
    while(r<=1)
    {
        I2C_status = I2CA_WriteData(I2C_SLAVE_ADDR, I2C_EEPROM_ADDRESS+r*64, TXdata, 64);
        DEVICE_DELAY_US(WRITE_DELAY_TIME); //wait for 5ms for max write time for EEPROM i'm using
        r++;
    }

    I2C_status = I2CA_ReadData(I2C_SLAVE_ADDR, I2C_EEPROM_ADDRESS, RXdata, 128);

    ESTOP0;


    TXdata[2] = 0;
    I2C_status = I2CA_WriteData(I2C_SLAVE_ADDR, I2C_EEPROM_ADDRESS, TXdata, 1);
    DEVICE_DELAY_US(WRITE_DELAY_TIME); //wait for 5ms for max write time for EEPROM i'm using

    I2C_status = I2CA_ReadData(I2C_SLAVE_ADDR, I2C_EEPROM_ADDRESS, RXdata, 1);

    TXdata[2] = 1;
    TXdata[3] = 2;
    I2C_status = I2CA_WriteData(I2C_SLAVE_ADDR, I2C_EEPROM_ADDRESS+1, TXdata, 2);
    DEVICE_DELAY_US(WRITE_DELAY_TIME); //wait for 5ms for max write time for EEPROM i'm using

    I2C_status = I2CA_ReadData(I2C_SLAVE_ADDR, I2C_EEPROM_ADDRESS, RXdata, 3);

    TXdata[2] = 3;
    TXdata[3] = 4;
    TXdata[4] = 5;
    TXdata[5] = 6;
    I2C_status = I2CA_WriteData(I2C_SLAVE_ADDR, I2C_EEPROM_ADDRESS+3, TXdata, 4);
    DEVICE_DELAY_US(WRITE_DELAY_TIME); //wait for 5ms for max write time for EEPROM i'm using

    I2C_status = I2CA_ReadData(I2C_SLAVE_ADDR, I2C_EEPROM_ADDRESS, RXdata, 7);

    ESTOP0;

    r = 2;
    while(r<=66)
    {

       TXdata[r] = 100 + r - 2;
       RXdata[r] = 0;
       r++;
    }

    I2C_status = I2CA_WriteData(I2C_SLAVE_ADDR, I2C_EEPROM_ADDRESS+64, TXdata, 64);
    DEVICE_DELAY_US(WRITE_DELAY_TIME); //wait for 5ms for max write time for EEPROM i'm using

    I2C_status = I2CA_ReadData(I2C_SLAVE_ADDR, I2C_EEPROM_ADDRESS, RXdata, 128);

    ESTOP0;

    I2C_status = I2CA_ReadData(I2C_SLAVE_ADDR, I2C_EEPROM_ADDRESS+3, RXdata, 10);

    I2C_status = I2CA_WriteData(I2C_SLAVE_ADDR, I2C_EEPROM_ADDRESS+128, TXdata, 64);
    DEVICE_DELAY_US(WRITE_DELAY_TIME); //wait for 5ms for max write time for EEPROM i'm using

    I2C_status = I2CA_ReadData(I2C_SLAVE_ADDR, I2C_EEPROM_ADDRESS, RXdata, 128);

    I2C_status = I2CA_ReadData(I2C_SLAVE_ADDR, I2C_EEPROM_ADDRESS+128, RXdata, 128);

    I2C_status = I2CA_ReadData(I2C_SLAVE_ADDR+10, I2C_EEPROM_ADDRESS+128, RXdata, 17);

    ESTOP0;

}

//
// I2CA_Init - Initialize I2CA settings
//
void I2CA_Init(void)
{
    I2caRegs.I2CSAR.all = 0x0050;     // Slave address - EEPROM control code

    I2caRegs.I2CPSC.all = 11;         // Prescaler - need 7-12 Mhz on module clk //I2C Module clock = 100 MHz / (9+1) = 10 MHz
    I2caRegs.I2CCLKL = 45;            // NOTE: must be non zero //I2C configured in standard mode
    I2caRegs.I2CCLKH = 45;             // NOTE: must be non zero
    I2caRegs.I2CIER.all = 0x24;       // Enable SCD & ARDY __interrupts

    I2caRegs.I2CMDR.all = 0x0020;     // Take I2C out of reset
                                      // Stop I2C when suspended

    I2caRegs.I2CFFTX.all = 0x6000;    // Enable FIFO mode and TXFIFO
    I2caRegs.I2CFFRX.all = 0x2040;    // Enable RXFIFO, clear RXFFINT,

    return;
}

//
// I2CA_WriteData - Transmit I2CA message
//
Uint16 I2CA_WriteData(Uint16 SlaveAddress, Uint16 address, Uint16 *txbuffer, Uint16 NumOfBytes)
//Uint16 I2CA_WriteData(uint16_t SlaveAddress, Uint16 address)
{
    Uint16 status;

    Uint16 numofSixteenByte  = (2+NumOfBytes) / I2C_FIFO_LEVEL;
    Uint16 remainingBytes    = (2+NumOfBytes) % I2C_FIFO_LEVEL;

    status = checkBusStatus();
    if(status)
    {
        return status;
    }

    //
    // Setup slave address
    //
    I2caRegs.I2CSAR.all = SlaveAddress;


    txbuffer[0] = address >> 8;
    txbuffer[1] = (address) & 0xFF;

    I2caRegs.I2CCNT = 2+NumOfBytes;
    I2caRegs.I2CMDR.all = 0x6E20;
    F28x_usDelay(3000);

    status = handleNACK();
    if(status)
    {
       return status;
    }

    Uint16 count,i;

    count = 0;
    while(count < numofSixteenByte)
    {
        for(i=1;i<=I2C_FIFO_LEVEL;i++)
        {
            I2caRegs.I2CDXR.all = *(txbuffer);
            txbuffer++;
            status = handleNACK();
            if(status)
            {
               return status;
            }
        }

        count++;
        while(I2caRegs.I2CFFTX.bit.TXFFST);
    }

    //I2caRegs.I2CCNT = remainingBytes;
    for (i=0; i < remainingBytes; i++)
    {
        I2caRegs.I2CDXR.all = *(txbuffer);
        txbuffer++;
        status = handleNACK();
        if(status)
        {
          return status;
        }
    }

    while(I2caRegs.I2CMDR.bit.STP);
    //
    // Send start as master transmitter
    //
    status = I2C_SUCCESS;

    return status;
}

//
// I2CA_ReadData - Read I2CA Message
//
Uint16 I2CA_ReadData(uint16_t SlaveAddress, uint16_t address, uint16_t *rxbuffer, uint16_t NumOfBytes)
{

    Uint16 status;

    Uint16 numofSixteenByte  = NumOfBytes / I2C_FIFO_LEVEL;
    Uint16 remainingBytes    = NumOfBytes % I2C_FIFO_LEVEL;

    status = checkBusStatus();
    if(status)
    {
      return status;
    }
    //
    // Setup slave address
    //
    I2caRegs.I2CSAR.all = SlaveAddress;

    //
    // Setup number of bytes to send
    // MsgBuffer + Address
    //
    I2caRegs.I2CCNT = 2; //Additional 2 bytes for transmitting eeprom address

    //
    // Setup data to send
    //
    I2caRegs.I2CDXR.all = address >> 8;
    I2caRegs.I2CDXR.all = (address) & 0xFF;

    I2caRegs.I2CFFTX.bit.TXFFINTCLR = 1;

    I2caRegs.I2CMDR.all = 0x6620;
    F28x_usDelay(5000);

    status = handleNACK();
    if(status)
    {
      return status;
    }

    remainingBytes    = NumOfBytes % I2C_FIFO_LEVEL;
    while(I2caRegs.I2CFFTX.bit.TXFFST);

    I2caRegs.I2CCNT = NumOfBytes;    // Setup how many bytes to expect

    I2caRegs.I2CMDR.all = 0x6C20;    // Send restart as master receiver

    Uint16 count,i;

    count = 0;
    while(count < numofSixteenByte)
    {
        status = handleNACK();
        if(status)
        {

          return status;
        }

        count++;
        while(!(I2caRegs.I2CFFRX.bit.RXFFST == 16));

        for(i=0; i<I2C_FIFO_LEVEL; i++)
        {
            *rxbuffer = I2caRegs.I2CDRR.all;
            rxbuffer++;
        }

    }

    while(!(I2caRegs.I2CFFRX.bit.RXFFST == remainingBytes));
    for(i=0; i<remainingBytes; i++)
    {
           *rxbuffer = I2caRegs.I2CDRR.all;
           rxbuffer++;
    }

    status = handleNACK();
    if(status)
    {
      return status;
    }


    while(I2caRegs.I2CMDR.bit.STP);

    return I2C_SUCCESS;
}

Uint16 checkBusStatus(void)
{
    if(I2caRegs.I2CMDR.bit.STP == 1)
    {
     // ESTOP0;
        return I2C_STP_NOT_READY_ERROR;
    }
    if(I2caRegs.I2CSTR.bit.BB == 1)
    {
        ESTOP0;
        return I2C_BUS_BUSY_ERROR;
    }

    if(I2caRegs.I2CSTR.bit.NACK)
    {
        ESTOP0;
        return SLAVE_NOT_READY_ERROR;
    }

    return 0;

}

Uint16 handleNACK(void)
{
    if(I2caRegs.I2CSTR.bit.NACK)
    {
        I2caRegs.I2CSTR.bit.NACK = 1; //Clear NACK bit to receive future NACKs
        I2caRegs.I2CFFTX.bit.TXFFRST = 0; //Reset TX FIFO to flush FIFO
        I2caRegs.I2CMDR.bit.STP = 1;      //Generate STOP condition
        I2caRegs.I2CFFTX.bit.TXFFRST = 1; //Re-enable TX FIFO

        return SLAVE_NOT_READY_ERROR;
    }

    return 0;
}

//
// i2c_int1a_isr - I2CA ISR
//
__interrupt void i2c_int1a_isr(void)
{
//    Uint16 IntSource;

    //
    // Read __interrupt source
    //
//    IntSource = I2caRegs.I2CISRC.all;



    //
    // Enable future I2C (PIE Group 8) __interrupts
    //
    PieCtrlRegs.PIEACK.all = PIEACK_GROUP8;
}

//
// pass - Halt debugger and signify pass
//
void pass()
{
    __asm("   ESTOP0");
    for(;;);
}

//
// fail - Halt debugger and signify fail
//
void fail()
{
    __asm("   ESTOP0");
    for(;;);
}

//
// End of file
//
/*
void i2c_init_old(void)
{

//Assign GetWordData to the I2C-A version of the
//function. GetWordData is a pointer to a function.
//GetWordData = I2C_GetWord;

I2C_GPIO_confi(); //configure the GPIO for I2C

EALLOW;
//CpuSysRegs.PCLKCR9.bit.I2C_A = 1; // Turn I2C module clock on
// EDIS;

// Initialize I2C in master transmitter mode
I2caRegs.I2CFFRX.bit.RXFFIL = 3;
I2caRegs.I2CSAR.all= 0x68; //50// Slave address - EEPROM control code
I2caRegs.I2CPSC.all =0X14; //9 I2C clock should be between 7Mhz-12Mhz 50MHz/6=8.33
I2caRegs.I2CCLKL = 40; //43 // Pre scalers set for 100kHz bit rate
I2caRegs.I2CCLKH = 40; //43 // At a 10Mhz I2C clock

I2caRegs.I2CMDR.all = 0x0620; // Master transmitter
// Take I2C out of reset
// Stop when suspended

I2caRegs.I2CFFTX.all = 0x6000; // Enable FIFO mode and TXFIFO
I2caRegs.I2CFFRX.all = 0x2000; // Enable RXFIFO

EDIS;
return;
}
*/

void I2C_GPIO_confi(void)
{
    GPIO_SetupPinOptions(104, GPIO_INPUT, (GPIO_ASYNC | GPIO_PULLUP));
    GPIO_SetupPinMux(104, GPIO_MUX_CPU1, 1);

    GPIO_SetupPinOptions(105, GPIO_INPUT, (GPIO_ASYNC | GPIO_PULLUP));
    GPIO_SetupPinMux(105, GPIO_MUX_CPU1, 1);
}


/*
 * main.c
 *
 *  Created on: 31-Aug-2020
 *      Author: shakti
 */