STM32F20x USART3

[Tabulous]

Dont seem to be able to recieve data on USART3.

It is a 100 pin device and have it setup on PC10 and PC11, using alternate function 7.

I can send data out of USART3 ok using

chprintf((BaseSequentialStream*)&SD3, "Test String!! \r\n");

But i cant receive data, my recieve thread is this.

Code: Select all

static msg_t ThreadBacta(void *arg)
{
msg_t charbuf;
flagsmask_t flags;
BACTA_ST *ps = &pd;
EventListener elBactadata;

    (void)arg;

    chRegSetThreadName("bacd");
    sdStart(&SD3, &bactaconfig);

    chEvtRegisterMask((EventSource *)chnGetEventSource(&SD3),
                      &elBactadata, EVENT_MASK(1));

    while(TRUE)
    {
        bactaCommsHandler(ps);

        flags = chEvtGetAndClearFlags(&elBactadata);

        if(flags & CHN_INPUT_AVAILABLE)
        {
           do
           {
              charbuf = chnGetTimeout(&SD3, TIME_IMMEDIATE);

              if ( charbuf != Q_TIMEOUT )
              {
//                  chprintf((BaseSequentialStream*)&SD3, "%c", charbuf);

                  decodeBactaStatemachine( ps, (char)charbuf );
              }
           }
           while (charbuf != Q_TIMEOUT);
        }

        chEvtWaitOneTimeout(EVENT_MASK(1), MS2ST(10));
    }

    return( 0 );
}

decodeBactaStatemachine is never called, which i would except if there was data been recieved

[Giovanni]

Is the problem related to the code (it looks OK) or SD3 itself? you may try another USART.

Giovanni

[Tabulous]

with relation to SD3. If i change to SD6 everything works oks.

As i said it seems to be the recieve on SD3 that is not firing an event ?

[Giovanni]

It could be a bug, for example an ISR not linked correctly to its vector. I'll verify.

Giovanni

[Giovanni]

I don't see obvious errors in the driver and definitions, are you using an F4?

Try putting a breakpoint into the ISR and see if it is triggered, if not verify the HW RX line (connected, conflicted etc).

Giovanni

[Tabulous]

F2 as per title of this post

I can see data on Pin79 which is USART3_RX with scope, but i dont get any interrupts on

Code: Select all

CH_IRQ_HANDLER(STM32_USART3_HANDLER) {

  CH_IRQ_PROLOGUE();

  serve_interrupt(&SD3);

  CH_IRQ_EPILOGUE();
}

[Giovanni]

Is the UART3 RX signal declared alternate on a single pin? verify your board.h.

Giovanni

[Tabulous]

PC10 and PC11 are set to Alternate 7, which is USART3_TX and USART3_RX respectively.

[Giovanni]

Just PC10 and PC11 or you have some alt(7) on other pins? that is forbidden.

You may inspect the USART registers and see if some data is received but not handled by the driver. I doubt that, most likely the signal does not get to the USART for some reason.

Giovanni

[Tabulous]

Right alt(7) is also use on another USART this might be the issue.....