TMS570LC4 SCI Receive Interrupt problem

Werner Motz

Intellectual 585 points

Other Parts Discussed in Thread: HALCOGEN

Hello,

I hope someone can help me:

I am using Halcogen 04.04 and want to receive messages on SCI1 via interrupt.

Sending works fine. I connected TX and RX with each other and after sending,

the receive interrupt SCI1HighLevelInterrupt(void) gets called TWICE. Unfortunately the

callback function sciNotification(sciREG1, (uint32)SCI_RX_INT) never gets called

because *g_sciTransfer_t[0U].rx_length is always = 0. Because I scoped the

TX signal with an oscilloscope I am sure that I sent a byte. Vec is also correct

(11 = Receive interrupt).

void SCI1HighLevelInterrupt(void)
{
    uint32 vec = sciREG1->INTVECT0;
	uint8 byte;

/* USER CODE BEGIN (28) */
/* USER CODE END */

    switch (vec)
    {
    case 1U:
        sciNotification(sciREG1, (uint32)SCI_WAKE_INT);
        break;
    case 3U:
        sciNotification(sciREG1, (uint32)SCI_PE_INT);
        break;
    case 6U:
        sciNotification(sciREG1, (uint32)SCI_FE_INT);
        break;
    case 7U:
        sciNotification(sciREG1, (uint32)SCI_BREAK_INT);
        break;
    case 9U:
        sciNotification(sciREG1, (uint32)SCI_OE_INT);
        break;

    case 11U:
        /* receive */
        byte = (uint8)(sciREG1->RD & 0x000000FFU);

            if (g_sciTransfer_t[0U].rx_length > 0U)
            {
                *g_sciTransfer_t[0U].rx_data = byte;
                g_sciTransfer_t[0U].rx_data++;
                
                g_sciTransfer_t[0U].rx_length--;
                if (g_sciTransfer_t[0U].rx_length == 0U)
                {
                    sciNotification(sciREG1, (uint32)SCI_RX_INT);
                }
            }
        
        break;

Why is g_sciTransfer_t[0U].rx_length always 0??? What am I doing wrong?

I am looking forward to your answer(s).

Kindly regards.

Werner

over 10 years ago

0 Vineeth Thomas Alex over 10 years ago

TI__Intellectual 1855 points

Hi Werner,

I think you need to call sciReceive() before getting the receive interrupt.
g_sciTransfer_t[0U].rx_length is configured using this function. Can you check if you are doing this while we wait for an expert's opinion?

Thanks and Regards,
Vineeth

0 Werner Motz over 10 years ago in reply to Vineeth Thomas Alex

Intellectual 585 points

Hi,
Thank you for your answer. My application is Interrupt driven, where should I call sciReceive()?

0 Vineeth Thomas Alex over 10 years ago in reply to Werner Motz

TI__Intellectual 1855 points

Since you're using Loopback method, I think you can use it right after sciSend(). You can go ahead and try this. I will still confirm this with an expert and get back to you.

Thanks and Regards,
Vineeth

0 Chuck Davenport over 10 years ago

TI__Guru 59540 points

Hello Werner,

Is it possible for you to post a zip file with your entire project so that I can debug it on my bench? If not can you post your Halcogen project (dil and hcg) files and sys_main.c?

0 Werner Motz over 10 years ago in reply to Chuck Davenport

Intellectual 585 points

Hello,

Thank you very much for your answer. I tried calling sciReceive() before the interrupt without success.

Please have a look on my project.

8780.TMS570LC4.zip

0 Werner Motz over 10 years ago in reply to Vineeth Thomas Alex

Intellectual 585 points

I tried again calling sciReceive() before the interrupt is called (physical loopback mode) and I really can receive the byte I sent. Now I want to receive messages not in loopback mode. I cannot call sciReceive() before interrupt because if I do not use loopback mode, I don't know when a message is sent. Any idea what to do?

0 Chuck Davenport over 10 years ago in reply to Werner Motz

TI__Guru 59540 points

Hello Werner,

Unfortunately, this thread got overlooked and left hanging. Are you still having the issue described in the thread or have you been able to work through it?

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TMS570LC4 SCI Receive Interrupt problem