MSPM0G1507: When communicating in Fast-mode (400kHz), the controller side shifts the data by 1 byte in repeated start operation

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#include "ti_msp_dl_config.h"

/* Maximum size of TX packet */
#define I2C_TX_MAX_PACKET_SIZE (16)

/* Maximum size of RX packet */
#define I2C_RX_MAX_PACKET_SIZE (16)

/* Data sent to Controller in response to Read transfer */
uint8_t gTxPacket[I2C_TX_MAX_PACKET_SIZE] = {0x00};

/* Counters for TX length and bytes sent */
uint32_t gTxLen, gTxCount;
uint8_t TX_Flag;
/* Data received from Controller during a Write transfer */
uint8_t gRxPacket[I2C_RX_MAX_PACKET_SIZE];
/* Counters for TX length and bytes sent */
uint32_t gRxLen, gRxCount;

int main(void)
{
    SYSCFG_DL_init();

    /* Set LED to indicate start of transfer */
    //DL_GPIO_setPins(GPIO_LEDS_PORT, GPIO_LEDS_USER_LED_1_PIN);

    /*
     * Fill FIFO with data.
     * Note that transactions are initiated by the Controller, so this example
     * only fills the buffer and the Target device will send this data when
     * requested by the Controller.
     * The TX FIFO is initialized to zero and then it will echo the data sent
     * by Controller.
     */
     TX_Flag = 0;
    gTxCount = 0;
    gTxLen   = I2C_TX_MAX_PACKET_SIZE;
    DL_I2C_enableInterrupt(I2C_INST, DL_I2C_INTERRUPT_TARGET_TXFIFO_TRIGGER);

    /* Initialize variables to receive data inside RX ISR */
    gRxCount = 0;
    gRxLen   = I2C_RX_MAX_PACKET_SIZE;

    NVIC_EnableIRQ(I2C_INST_INT_IRQN);

    /* Calling WFI after calling DL_SYSCTL_enableSleepOnExit will result in
     * only ISR code to be executed. This is done to showcase the device's
     * low power consumption when sleeping.
     */
    DL_SYSCTL_enableSleepOnExit();

    while (1) {
        __WFI();
    }
}

void I2C_INST_IRQHandler(void)
{
    static bool dataRx = false;
 DL_GPIO_setPins(GPIO_LEDS_PORT, GPIO_LEDS_USER_LED_1_PIN);
    switch (DL_I2C_getPendingInterrupt(I2C_INST)) {
        case DL_I2C_IIDX_TARGET_START:
            /* Initialize RX or TX after Start condition is received */

            gRxCount = 0;
            dataRx   = false;
            /* Flush TX FIFO to refill it */
            if(TX_Flag == 0)
            {
                DL_I2C_flushTargetTXFIFO(I2C_INST);
                gTxCount = 0;
            }

             
            break;
        case DL_I2C_IIDX_TARGET_RXFIFO_TRIGGER:
            /* Store received data in buffer */
            dataRx = true;
            while (DL_I2C_isTargetRXFIFOEmpty(I2C_INST) != true) {
                if (gRxCount < gRxLen) {
                    gRxPacket[gRxCount++] = DL_I2C_receiveTargetData(I2C_INST);
                } else {
                    /* Prevent overflow and just ignore data */
                    DL_I2C_receiveTargetData(I2C_INST);
                }
            }
            if (dataRx == true) {
                for (uint16_t i = 0;
                     (i < gRxCount) && (i < I2C_TX_MAX_PACKET_SIZE); i++) {
                    gTxPacket[i] = gRxPacket[i];
                    DL_I2C_flushTargetTXFIFO(I2C_INST);
                }
                gTxCount = 0;
                gTxCount += DL_I2C_fillTargetTXFIFO(
                    I2C_INST, &gTxPacket[gTxCount], (gTxLen - gTxCount));
                TX_Flag = 1;
            }

            break;
        case DL_I2C_IIDX_TARGET_TXFIFO_TRIGGER:
            /* Fill TX FIFO if there are more bytes to send */
            if (gTxCount < gTxLen) {
                gTxCount += DL_I2C_fillTargetTXFIFO(
                    I2C_INST, &gTxPacket[gTxCount], (gTxLen - gTxCount));
            } else {
                /*
                 * Fill FIFO with 0x00 if more data is requested than
                 * expected gTxLen
                 */
                while (DL_I2C_transmitTargetDataCheck(I2C_INST, 0x00) != false)
                    ;
            }
            DL_GPIO_togglePins(GPIO_LEDS_PORT, GPIO_LEDS_PIN_0_PIN);
            break;
        case DL_I2C_IIDX_TARGET_STOP:
            /* If data was received, echo to TX buffer */
            if (dataRx == true) {
                for (uint16_t i = 0;
                     (i < gRxCount) && (i < I2C_TX_MAX_PACKET_SIZE); i++) {
                    gTxPacket[i] = gRxPacket[i];
                    DL_I2C_flushTargetTXFIFO(I2C_INST);
                }
                gTxCount = 0;
                gTxCount += DL_I2C_fillTargetTXFIFO(
                    I2C_INST, &gTxPacket[gTxCount], (gTxLen - gTxCount));
                TX_Flag = 1;
                dataRx = false;
            }else {
            TX_Flag = 0;
            }
        

            
            /* Toggle LED to indicate successful RX or TX */
           
            break;
        case DL_I2C_IIDX_TARGET_RX_DONE:
            /* Not used for this example */
        case DL_I2C_IIDX_TARGET_RXFIFO_FULL:
            /* Not used for this example */
        case DL_I2C_IIDX_TARGET_GENERAL_CALL:
            /* Not used for this example */
        case DL_I2C_IIDX_TARGET_EVENT1_DMA_DONE:
            /* Not used for this example */
        case DL_I2C_IIDX_TARGET_EVENT2_DMA_DONE:
            /* Not used for this example */
        default:
            break;
    }
     DL_GPIO_clearPins(GPIO_LEDS_PORT, GPIO_LEDS_USER_LED_1_PIN);
}