RTOS/TDA2P-ACD: Unable To Receive Databytes over UART2

Abhay Sorte

Part Number: TDA2P-ACD

Tool/software: TI-RTOS

Hello,

I am working with TDA2P based customized board in which TDA2P is interfaced to a safety micro TI TMS570. I am using Processor SDK 03.03.

I am trying to establish a communication between TDA2P and TMS over UART. TDA2P's UART2 (instance 1) is interfaced to the UART of TMS.

For TDA2P, I referred to "uart_echo" example code from "PROCESSOR_SDK_VISION_03_03_00_00/ti_components/drivers/pdk_01_09_00_17/packages/ti/drv/bsp_lld/uart/examples". Using this example code, I have created an application which has a read task to read data over UART2 from TMS.

Currently, the data bytes sent by TDA2P are received by TMS but TDA2P does not receive anything from TMS. I debugged the code to find out that in the read task, my code never comes out of the GIO_read API call.

Below code is UART init and my read task,

    /* Adding UART2 device */
    status = GIO_addDevice("/uart1", (xdc_Ptr) &Uart_IOMFXNS, &init_UART,
    UART2_INSTANCE, (xdc_Ptr) &uartParams);

void init_UART(void)
{
    uartParams = Uart_PARAMS;
    uartParams.opMode = UART_OPMODE_POLLED;
    uartParams.hwiNumber = 8U;
    uartParams.rxThreshold = UART_RXTRIGLVL_8;
    uartParams.txThreshold = UART_TXTRIGLVL_56;
    uartParams.baudRate = UART_BAUDRATE_115_2K;
    uartParams.charLen = UART_CHARLEN_8;
    uartParams.stopBits = UART_NUMSTOPBITS_1;
    uartParams.parity = UART_PARITY_NO;
    uartParams.prcmDevId = 1; /* 1 is instance number of UART2 */
}

void uart2_ReadTsk(void)
{
    Bool exitLoop = FALSE;
    size_t len = 0, totalLen = 0;
    char *pRxBuf = NULL;
    Int status = IOM_COMPLETED;

    /* Now the user will input a string of APP_UART_NUM_BYTES bytes.
     * Hence submit a read request for APP_UART_NUM_BYTES bytes and loop
     * till we receive that many bytes */
    while (exitLoop != TRUE)
    {
        len = APP_UART_NUM_BYTES - totalLen;
        status = GIO_read(uartRxHndl, &uart2RxBuf[totalLen], &len);
        if (IOM_COMPLETED != status)
        {
            /* Report Error */
            Vps_printf("\r\nUART : GIO_read failed. returned : %d \r\n",
                       status);
        }

        totalLen += len;
         if (totalLen >= APP_UART_NUM_BYTES)
         {
         exitLoop = TRUE;
         }
    }

    return;
}

I have highlighted the GIO_read call where my code hangs. I have not called "Uart_init()" as it already called from Utils functions during init.

Can anyone suggest what can be the issue here as I am able to transmit data but I am not able to receive any data over UART2.

Regards,

Abhay

over 5 years ago

0 Prasad Konnur over 5 years ago

TI__Expert 6065 points

Hi Abhay,

The GIO_read is a blocking call and the function will not return unless the len number of bytes are received or LF/CR is received.

Can you check if the pinmux is done for hte Rx lines?

Also note that the instance numbers in driver (parameter to GIO_addDevice) starts from 0.
Make sure you have initialized the driver for proper instance which is connected on your EVM.

Regards,
Prasad

0 Abhay Sorte over 5 years ago in reply to Prasad Konnur

Genius 4105 points

Hi Prasad,

Thanks for your reply.
I have done the pinmuxing for UART2 and checked the registers in memory browser. Also proper instance num (1 for UART2) is given to GIO_addDevice API.
I think TMS is not sending len number of bytes to TDA2P that's why GIO_read API is blocked. I will check this and update you.

Thanks,
Abhay

0 Rishabh Garg over 5 years ago in reply to Abhay Sorte

TI__Guru 55685 points

Hi Abhay,

As a quick experiment you can send one byte data from TMS and receive it on TDA2P.
This will confirm if the connection is fine.

Regards,
Rishabh

0 Abhay Sorte over 5 years ago in reply to Rishabh Garg

Genius 4105 points

Hi Prasad,

I tried by sending len number of bytes from TMS side, still GIO_read() is blocked. Can you verify my below UART settings and let me know if anything is missing.

Uint32 configureUART(void)
{
    Uint32 status = uSTATUS_OK;
    Uart_ChanParams chanParams;
    Error_Block eb;
    GIO_Params ioParams;

    status = GIO_addDevice("/uart1", (xdc_Ptr) &Uart_IOMFXNS, &init_UART, 1U, (xdc_Ptr) &uartParams);

    Error_init(&eb);

    /* Initialize channel attributes */
    GIO_Params_init(&ioParams);

    /* Cross bar event disabled */
    chanParams.crossBarEvtParam.isCrossBarIntEn = (UInt32) TRUE/*FALSE*/;
    chanParams.crossBarEvtParam.intNumToBeMapped = CSL_XBAR_INST_IPU1_IRQ_31/*0xFF*/;

    ioParams.chanParams = (Ptr) &chanParams;
    ioParams.model = GIO_Model_STANDARD;

    /* create the required channels(TX/RX) for the UART2 */
    uartTxHndl = GIO_create("/uart1", GIO_OUTPUT, &ioParams, &eb);
    uartRxHndl = GIO_create("/uart1", GIO_INPUT, &ioParams, &eb);

    if ((NULL == uartRxHndl) || (NULL == uartTxHndl))
    {
        status = uSTATUS_FAIL;
    }

    return status;
}

void init_UART(void)
{
    UInt32 uartDevId = 1U;
    DEV_Params devParams;

    uartParams = Uart_PARAMS;
    uartParams.opMode = UART_OPMODE_POLLED;
    uartParams.hwiNumber = CSL_XBAR_INST_IPU1_IRQ_31; //8U or 9U;
    uartParams.rxThreshold = UART_RXTRIGLVL_8;
    uartParams.txThreshold = UART_TXTRIGLVL_56;
    uartParams.baudRate = UART_BAUDRATE_115_2K;
    uartParams.charLen = UART_CHARLEN_8;
    uartParams.stopBits = UART_NUMSTOPBITS_1;
    uartParams.parity = UART_PARITY_NO;
    uartParams.prcmDevId = 1; /* 1 is instance number of UART2 */
    uartParams.enableCache = (Bool) FALSE;

    DEV_Params_init(&devParams);
    devParams.deviceParams = &uartParams;
    devParams.initFxn = NULL;
    devParams.devid = uartDevId;
}

With the above settings I am able to transmit over UART2 though.

Hi Rishabh,

I tried by sending a single byte data from TMS to TDA2P. But GIO_read() call on TDA2P is not receiving anything.

Regards,

Abhay

0 Rishabh Garg over 5 years ago in reply to Abhay Sorte

TI__Guru 55685 points

Hi Abhay,

Is pin mux fine? Can you probe and check if any data is being sent by TMS.

Regards,
Rishabh

0 Abhay Sorte over 5 years ago in reply to Rishabh Garg

Genius 4105 points

Hi Rishabh,

Yes I checked the register values in the memory browser of CCS for which I am doing the pinmux as below and I was able to read the values which were set.

void PlatformUART2SetPinMux(void)
{
/* Pin_num, Muxmode, pullud_enable, pull_typeselect, io, slewrate, wakeupmode */
HW_WR_REG32(SOC_CORE_PAD_IO_REGISTERS_BASE + CTRL_CORE_PAD_UART2_TXD, //UART2 TXD
0x00000);
HW_WR_REG32(SOC_CORE_PAD_IO_REGISTERS_BASE + CTRL_CORE_PAD_UART2_RXD, //UART2 RXD
0x40000);

/* Enabling UART2 CLK */
HW_WR_REG32(SOC_L4PER_CM_CORE_BASE + CM_L4PER_UART2_CLKCTRL, PRCM_ENABLE);
while ((HW_RD_REG32(SOC_L4PER_CM_CORE_BASE + CM_L4PER_UART2_CLKCTRL)
& ((UInt32) (0x00030000))) != 0x0)
{
/* Do nothing - Busy wait */
}
}

I will check for probe points on our custom board to see whether TMS is sending the data or not.

Thanks,
Abhay

0 Rishabh Garg over 5 years ago in reply to Abhay Sorte

TI__Guru 55685 points

Hi Abhay,

Can you also see what is the value of CM_L4PER_UART2_CLKCTRL register.

Regards,
Rishabh

0 Abhay Sorte over 5 years ago in reply to Rishabh Garg

Genius 4105 points

Hi Rishabh,

The value of CM_L4PER_UART2_CLKCTRL (0x4A009848) was read as 0x00000002.

Regards,
Abhay

0 Rishabh Garg over 5 years ago in reply to Abhay Sorte

TI__Guru 55685 points

Hi Abhay,

PRCM seems fine. Can you probe and see if TMS is sending data as suggested earlier.

Regards,
Rishabh

0 Abhay Sorte over 5 years ago in reply to Rishabh Garg

Genius 4105 points

Hi Rishabh,

I probed and found that data is sent by TMS on UART. But TDA2P does not receive anything.

Can you verify my UART settings from the above post. Am I missing anything.

Regards,

Abhay

0 Abhay Sorte over 5 years ago in reply to Abhay Sorte

Genius 4105 points

Hi Rishabh,

Do you think I have missed anything in UART settings ?

Regards,
Abhay

0 Abhay Sorte over 5 years ago in reply to Abhay Sorte

Genius 4105 points

Hi Rishabh,

Can you guide us where exactly to look for to solve this issue.

Thanks,
Abhay

0 Prasad Konnur over 5 years ago in reply to Abhay Sorte

TI__Expert 6065 points

Hi Abhay,

The pad configuration for UART2_Rxd looks incorrect.
For the pad CTRL_CORE_PAD_UART2_RXD, mux mode of 0 is reserved. You need to set mux mode to 4 for UART2_Rxd
Can you update that and check?

Regards,
Prasad

0 Abhay Sorte over 5 years ago in reply to Prasad Konnur

Genius 4105 points

Hi Prasad,

Thanks for reply. I will test it with the pin mux change suggested by you and will update you.

Regards,
Abhay

0 Abhay Sorte over 5 years ago in reply to Abhay Sorte

Genius 4105 points

Hi Prasad,

With the below pin mux settings we are able to receive data over UART2,

HW_WR_REG32(SOC_CORE_PAD_IO_REGISTERS_BASE + CTRL_CORE_PAD_UART2_TXD, //UART2 TXD
0x00004);
HW_WR_REG32(SOC_CORE_PAD_IO_REGISTERS_BASE + CTRL_CORE_PAD_UART2_RXD, //UART2 RXD
0x40004);

I have one more doubt regarding the number of bytes to be received. While calling GIO_read(), is it necessary to specify the number of bytes to be received ?

"
len = 8;
status = GIO_read(uartRxHndl, &uart2RxBuf, &len);
"

In the above code snippet, when I don't specify any value to "len", we don't receive anything.
If I want to receive random number of data bytes from TMS to TDA2P over UART2, how can I do that.

Regards,
Abhay

0 Rishabh Garg over 5 years ago in reply to Abhay Sorte

TI__Guru 55685 points

Hi Abhay,

Glad that the issue to receive data over UART2 is resolved.
GIO_read is used to read a specified number of data from the communication channel.
Hence you need to specify the number of bytes you want to read.

Regards,
Rishabh

0 Abhay Sorte over 5 years ago in reply to Rishabh Garg

Genius 4105 points

Hi Rishabh,

Ok. We will updated our code accordingly.
Thank you for your support.

Hi Prasad,

Thank you for your support.

Regards,
Abhay

0 Rishabh Garg over 5 years ago in reply to Abhay Sorte

TI__Guru 55685 points

Hi Abhay,

Kindly mark the post that answers your query as "This resolved my issue" and close the thread.

Regards,
Rishabh

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RTOS/TDA2P-ACD: Unable To Receive Databytes over UART2