UARTE Frame error receiving

[Thomas]

Hi

I am seing framing errors when receiving using UARTE.

It is not external hardware, I have checked with different other interfaces and measured timing, no problems there.

BUT, doing the same with UART instead of UARTE I do not get any framing errors (same hardware setup).

Actually with UARTE I only get one rx character then framing errors....

[Einar Thorsrud]

Hi,

I am not sure what is going on. A typical reason for UART framing errors is if you have a baud-rate mismatch between the two UART devices, for instance, if you have not started the high-frequency crystal oscillator. Can you try doing that? If that is not the problem (which may be unlikely, since you see a difference between using UART and UARTE), then we should probably look at your code.

[Thomas]

// Initialize uarte 

      nrfx_uarte_config_t config = NRFX_UARTE_DEFAULT_CONFIG;

      // Initialize uart 
      result = nrfx_uarte_init(&m_serial[id].uart, &config, SerialInterfaceEventHandler);
      APP_ERROR_CHECK(result);
      
      // Start receiving and specify buffer for double buffering
      result = nrfx_uarte_rx(&m_serial[id].uart, &m_serial[id].rxBuffer[0], 1);
      APP_ERROR_CHECK(result);
      result = nrfx_uarte_rx(&m_serial[id].uart, &m_serial[id].rxBuffer[1], 1);
      APP_ERROR_CHECK(result);

// Event handler

static void SerialInterfaceEventHandler(nrfx_uarte_event_t const * p_event, void* p_context)
{
   ret_code_t ret;
   int id = (uint32_t)p_context;
   
   switch (p_event->type)
   {
      case NRFX_UARTE_EVT_TX_DONE:   //!< Chunk of data has been sent.
         SerialCallEventHandler(id, SE_TX_COMPLETE);
         break;
      
      case NRFX_UARTE_EVT_RX_DONE:   //!< New chunk of data has been received.
         rxCount++;
         if (p_event->data.rxtx.bytes > 0)
         {
            SerialReceiveInsert(id, p_event->data.rxtx.p_data[0]);
         }
// Previous test, not sure if a new nrfx_uarte_rx call is needed when using 
// double buffering (but it works like below for UART interface
//         SerialReceiveInsert(id, m_serial[id].rxBuffer[m_serial[id].rxIndex]);
//         ret = nrfx_uarte_rx(&m_serial[id].uart, &m_serial[id].rxBuffer[m_serial[id].rxIndex], 1);
//         APP_ERROR_CHECK(ret);
//         m_serial[id].rxIndex = 1-m_serial[id].rxIndex;
         SerialCallEventHandler(id, SE_RX_READY);
         break;
         
      case NRFX_UARTE_EVT_ERROR:
         serError++;
         error = p_event->data.error.error_mask;
         SerialCallEventHandler(id, SE_ERROR);
         break;
   }
}

I have attached the basic initialization and eventhandler code. 

[Thomas]

Thanks - It seems there are multible locations for download, the one I found looked different and had latest 8.26.

I am not starting now but modifiying an existing project from using one uart to using two uarts. And that had shown to be very difficult.

Will SDK 16 require a SoftDevice update in my targets?

[Einar Thorsrud]

Hi,

Yes, SD 16 is only API compatible with version 7 SoftDevices (see SDKs and SoftDevices compatibility matrix).

[Thomas]

Fixed the device family pack thing, but a little bit messy as version 8.27 is not available so I can download 8.28 and then the example project still has error and complains, so the pack selection has to be fixed in the setup….

I will see if I can get it running with 15.3 to begin with.

[Einar Thorsrud]

Hi,

You can specify 8.28 in the Keil project though Under "Manage runtime environment", and changing the options of the Device in the project tree. But it is a bit of a hassle. SDK 15.3 should be just fine, though libuarte is improved in SDK 16 (first time out of experimental).

[Thomas]

I will try to copy the version from SDK 16 to SDK 15.3 and see if I succeed.