CC2652P: UART2 in SDK 6.10 can't trigger Send Callback

Hi,

I have modified the uart2callback in the following fashion, and I can see the write callback being executed:

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/*
 *  ======== uart2callback.c ========
 */
#include <stdint.h>
#include <stddef.h>

/* POSIX Header files */
#include <semaphore.h>

/* Driver Header files */
#include <ti/drivers/GPIO.h>
#include <ti/drivers/UART2.h>

/* Driver configuration */
#include "ti_drivers_config.h"

static sem_t sem;
static volatile size_t numBytesRead;
static volatile size_t numBytesWrite;
/*
 *  ======== callbackReadFxn ========
 */
void callbackReadFxn(UART2_Handle handle, void *buffer, size_t count,
        void *userArg, int_fast16_t status)
{
    if (status != UART2_STATUS_SUCCESS) {
        /* RX error occured in UART2_read() */
        while (1);
    }

    numBytesRead = count;
    sem_post(&sem);
}

/*
 *  ======== callbackWriteFxn ========
 */
void callbackWriteFxn(UART2_Handle handle, void *buffer, size_t count,
        void *userArg, int_fast16_t status)
{
    if (status != UART2_STATUS_SUCCESS) {
        /* RX error occured in UART2_read() */
        while (1);
    }

    numBytesWrite = count;
}

/*
 *  ======== mainThread ========
 */
void *mainThread(void *arg0)
{
    char              input;
    const char        echoPrompt[] = "Echoing characters:\r\n";
    UART2_Handle      uart;
    UART2_Params      uartParams;
    int32_t           semStatus;
    uint32_t          status = UART2_STATUS_SUCCESS;

    /* Call driver init functions */
    GPIO_init();

    /* Configure the LED pin */
    GPIO_setConfig(CONFIG_GPIO_LED_0, GPIO_CFG_OUT_STD | GPIO_CFG_OUT_LOW);

    /* Create semaphore */
    semStatus = sem_init(&sem, 0, 0);

    if (semStatus != 0) {
        /* Error creating semaphore */
        while (1);
    }

    /* Create a UART in CALLBACK read mode */
    UART2_Params_init(&uartParams);
    uartParams.readMode = UART2_Mode_CALLBACK;
    uartParams.readCallback = callbackReadFxn;
    uartParams.writeMode = UART2_Mode_CALLBACK;
    uartParams.writeCallback = callbackWriteFxn;
    uartParams.baudRate = 115200;

    uart = UART2_open(CONFIG_UART2_0, &uartParams);

    if (uart == NULL) {
        /* UART2_open() failed */
        while (1);
    }

    /* Turn on user LED to indicate successful initialization */
    GPIO_write(CONFIG_GPIO_LED_0, CONFIG_GPIO_LED_ON);

    /* Pass NULL for bytesWritten since it's not used in this example */
    UART2_write(uart, echoPrompt, sizeof(echoPrompt), NULL);

    /* Loop forever echoing */
    while (1) {
        numBytesRead = 0;

        /* Pass NULL for bytesRead since it's not used in this example */
        status = UART2_read(uart, &input, 1, NULL);

        if (status != UART2_STATUS_SUCCESS) {
            /* UART2_read() failed */
            while (1);
        }

        /* Do not write until read callback executes */
        sem_wait(&sem);

        if (numBytesRead > 0) {
            status = UART2_write(uart, &input, 1, NULL);

            if (status != UART2_STATUS_SUCCESS) {
                /* UART2_write() failed */
                while (1);
            }
        }
    }
}

Please make sure that you configured the writeMode to UART2_Mode_CALLBACK.

Regards,

Arthur