XMC™ Forum Discussions

Hello Forum.

I thought I had an understanding of the USIC (in UART mode).

I have a 20 byte buffer that I need to send packets out on to a listening peripheral.
However, I'm only seeing16 bytes. Well that's all the other side is receiving.

I am using an XMC4500.

My code is setup:

#define UART_RX				P3_12
#define UART_TX				P3_11

XMC_GPIO_CONFIG_t uart_tx =
{
	.mode = XMC_GPIO_MODE_OUTPUT_PUSH_PULL_ALT1,
	.output_level     = XMC_GPIO_OUTPUT_LEVEL_HIGH,
	.output_strength  = XMC_GPIO_OUTPUT_STRENGTH_STRONG_SOFT_EDGE
};
XMC_GPIO_CONFIG_t uart_rx =
{
	 .mode             = XMC_GPIO_MODE_INPUT_TRISTATE,
	.output_level     = XMC_GPIO_OUTPUT_LEVEL_HIGH,
	.output_strength  = XMC_GPIO_OUTPUT_STRENGTH_STRONG_SOFT_EDGE
};

XMC_UART_CH_CONFIG_t uart_config =
{

	.baudrate = 115200U,
	.data_bits     = 8U,
	.frame_length  = 8U,
	.stop_bits     = 1U,
	.oversampling  = 16U,
	.parity_mode   = XMC_USIC_CH_PARITY_MODE_NONE

};

/* code to setup uart */
	XMC_UART_CH_Init(XMC_UART2_CH1, &uart_config);
	XMC_UART_CH_SetInputSource(XMC_UART2_CH1, XMC_UART_CH_INPUT_RXD, USIC2_C1_DX0_P3_12);


	/* Setup FIFO's */
	XMC_USIC_CH_TXFIFO_Configure(XMC_UART2_CH1,32U,XMC_USIC_CH_FIFO_SIZE_32WORDS,1U);
	XMC_USIC_CH_RXFIFO_Configure(XMC_UART2_CH1,0U, XMC_USIC_CH_FIFO_SIZE_32WORDS,0U);

	XMC_UART_CH_Start(XMC_UART2_CH1);
	
	XMC_GPIO_Init(UART_TX,&uart_tx);
	XMC_GPIO_Init(UART_RX,&uart_rx);
	
	 /*Set service request for UART protocol events*/
	XMC_USIC_CH_SetInterruptNodePointer(XMC_UART2_CH1, XMC_USIC_CH_INTERRUPT_NODE_POINTER_PROTOCOL,0U);
  
	/*Set service request for tx FIFO transmit interrupt*/
	XMC_USIC_CH_TXFIFO_SetInterruptNodePointer(XMC_UART2_CH1, XMC_USIC_CH_TXFIFO_INTERRUPT_NODE_POINTER_STANDARD, 3U);
 
	/*Set service request for rx FIFO receive interrupt*/
	XMC_USIC_CH_RXFIFO_SetInterruptNodePointer(XMC_UART2_CH1, XMC_USIC_CH_RXFIFO_INTERRUPT_NODE_POINTER_STANDARD, 0x5U);
	XMC_USIC_CH_RXFIFO_SetInterruptNodePointer(XMC_UART2_CH1, XMC_USIC_CH_RXFIFO_INTERRUPT_NODE_POINTER_ALTERNATE, 0x5U);
	
	/*Set priority and enable NVIC node for transmit interrupt*/
	NVIC_SetPriority(USIC2_3_IRQn, NVIC_EncodePriority(NVIC_GetPriorityGrouping(), 63U, 0U));
	NVIC_EnableIRQ(USIC2_3_IRQn);
  
	/*Set priority and enable NVIC node for receive interrupt*/
	NVIC_SetPriority(USIC2_5_IRQn, NVIC_EncodePriority(NVIC_GetPriorityGrouping(), 63U, 0U));
	NVIC_EnableIRQ(USIC2_5_IRQn);
 
	/* Ready to receive */
	XMC_USIC_CH_RXFIFO_EnableEvent(XMC_UART2_CH1, (uint32_t)((uint32_t)XMC_USIC_CH_RXFIFO_EVENT_CONF_STANDARD | (uint32_t)XMC_USIC_CH_RXFIFO_EVENT_CONF_ALTERNATE));

Help? Show Less

Hi

To start with, a bit of background information:

I have a RaspberryPI with Apache webserver installed serving a webpage which sends messages to the activeMQ server using MQTT over websockets.
ActiveMQ is also installed on the RPi and it receives the messages. So this is working correctly.

What I like to achieve is that I can subscribe my XMC4800 to the activeMQ server such that I can receive these messages on the XMC4800.

Therefore, I have installed CMSIS RTX (Dave App) and also installed the CycloneTCP library* on my microcontroller. CycloneTCP is fully compatible with Infineon XMC microcontrollers and it has even some example code for the XMC4800.

Everything compiles fine and the CMSIS RTX example from the app runs correctly.
However, when I try to run the CycloneTCP example it seems that the microcontroller is blocking (?) while initialising the TCP/IP stack.

Code fragment of my main function:

int main(void) {
	DAVE_STATUS_t status;

	status = DAVE_Init(); /* Initialization of DAVE APPs  */

	SystemCoreClockUpdate();

	//Initialize kernel
	osInitKernel();
	ioInit();

	if (status == DAVE_STATUS_SUCCESS) {

		error_t error;
		OsTask *task;
		NetInterface *interface;

		MacAddr macAddr;

		Ipv4Addr ipv4Addr;

		//TCP/IP stack initialization
		error = netInit();
...

The source of the netInit() function ( http://www.oryx-embedded.com/doc/net_8c_source.html#l00101 ) executes on line# 120 the method below

/**
 * @brief Create an event object
 * @param[in] event Pointer to the event object
 * @return The function returns TRUE if the event object was successfully
 *   created. Otherwise, FALSE is returned
 **/

bool_t osCreateEvent(OsEvent *event)
{
   ...
   //Create a binary semaphore object
   event->id = osSemaphoreCreate(&semaphoreDef, 1);

   //Check whether the returned semaphore ID is valid
   if(event->id != NULL)
   {
      //Force the specified event to the nonsignaled state
      osSemaphoreWait(event->id, 0);
      //Event successfully created
      return TRUE;
   }
   else
   {
      //Failed to create event object
      return FALSE;
   }
}

The call to osSemaphoreWait(event->id, 0) does not return. However, the second parameter tells me that it should return immediately.
It seems that the micrcontroller is waiting for something but I cannot figure out what it could be.

I have little experience with RTOS and Networking, but if someone could help me with this, I would very much appreciate it.
I have debugged this to the very bottom and it ultimately blocks on the call to the assemby instruction BLX R4:



Maybe some extra usefull information:
- raspberryPi has a static IP address (10.0.0.2) and is connected using a crossover UTP cable with the XMC4800
- cycloneTCP has the appropriate drivers included for the PHY (ksz8081.h) and for the network interface (xmc4800_eth.h)

*CycloneTCP is a free (for non-commercial use) open-source full tcp/ip stack from http://www.oryx-embedded.com Show Less

Hello,

I have created a MUTLICAN+ program which runs smoothly in loop-back mode. If I switch off the loob-balck mode and try to send via a PCAN-View can messages to my XMC4700 Relax Kit or receive some from it, it does not work. My bus seem to be BUSHEAVY all the time. Now I am unsure whether I have something wrong in the configuration.

In order to send messages without Loob-Balck mode, I have to connect the respective pins (here: P1.12 and P1.13) to the MULTICAN_CONFIG APP, if I understood correctly?
Now I have created over two instances of the DIGITAL_IO APP and assigned them the two pins. Furthermore, I renamed the two instances to CAN_TX and CAN_RX.
CAN_TX was set as Input/Output and CAN_RX as Input. Now I would nevertheless in the "HW Signal Connections" tool of the MULTICAN_CONFIG APP assign the pins as well as the interrupt.

Now I have the problem that I can assign nothing to the transmit node (node0), as well as the receive node (node1). Only their counterparts, as seen below.

# event_lmo_01_rxinp -----> INTERUPT_0, sr_irq
# tx_pin_node1 -----> CAN_TX, pin
# rx_pin_node0 -----> MULTICAN_CONFIG_0, rx_pin_node1

This is the only configuration I could do but now it should really look more like this:

# event_lmo_01_rxinp -----> INTERUPT_0, sr_irq
# rx_pin_node1 -----> CAN_RX, pin
# tx_pin_node0 -----> CAN_TX, pin

However, these settings can not be made !?

I hope you can help me, how I can set with DAVE 4 in the latest version the pins for my XMC4700 Relax Kit correct for CAN right?
As already mentioned in Loop-Back mode everything works without errors!

Best regards
TUMstudent Show Less

In the reference manul for XMC45, figure 18-18 shows the transmission of a message object. According to the figure, the transmission is aborted and no interrupt is generated if transmission was not successful.

Questions:
1. Under what circumstances can the transmission fail?
2. If no interrupt is generated if transmission fails, then how is one to know that buffer is no longer in use by hardware? Show Less

Hi,

after transmitting many Bytes (more than the rx fifo can hold) to an spi eeprom I would like to flush the receive fifo by setting TRBSCR->FLUSHRB to 1. But the receive fifo will not be cleared. A second write to TRBSCR->FLUSHRB with 1 clears it. That behaviour occurs when the rx fifo is full.

If the rx fifo is not full (but holds some elements) I need to write TRBSCR->FLUSHRB only once (as noted in the datasheet).

USIC1 CH0 and CH1 are configured for 16 rx and 16 tx fifo Slots each. (64 fifo Slots on XMC4500 availabe).

Why do I Need to flush the rx fifo twice?

Regards

Tobias Show Less

We've got a board that originally had an XMC4400. We compiled and built code for it using IAR Embedded Workbench and everything was hunky dory. We replaced the XMC4400 with a 4500 and rebuilt the code telling the IAR compiler that the target was now a 4500. The resulting binary doesn't run.

Our next step is to add a connector to the board for a J-TAG, but I wanted to check first with this forum and see if there's something that needs to change other than just changing the target to "XMC4500" in the IAR tools. Show Less

Hello,

I am using DSD Demodulator on the XMC4500 with the Hexagon board.
I cannot get it to work with acquisitions synchronized to a PWM signal.
Is there any Dave4 example showing how to connect the EVENT_DETECTOR / GENERATOR that seem to be mandatory ?
Any help or suggestion is welcome

Jorge Show Less

Hello,

I'm using the XMC1302 Microcontroller for a BLDC Motor Control.
The clock of the controller ist set up with SystemInit to 32Mhz.

Now I have written a little function for a 1us delay.
To measure the time i use a GPIO Port.

void delay1us(void)

/*Turn LED on*/
PORT0->OUT |= 1<<12;

volatile uint16_t a;
for(a=0; a<1; a++);

/*Turn LED off*/
PORT0->OUT &= ~(1<<12);

With this code i measure a time of 1,7us.

/*Turn LED on*/
PORT0->OUT |= 1<<12;

/*Turn LED off*/
PORT0->OUT &= ~(1<<12);

With this code, I measure a time of 564ns.

Why ist this time so long when the clock ist set up to 32Mhz and the cycle time is 31ns?

Thanks for Your Response! Show Less

Hello.

I have a PWM working with a set frequency and duty cycle using CCU4, slice 0. I have functions that set the duty cycle and frequency of the slice.
But I am driving an external speaker alarm and it needs two different PWM frequency and duty cycles over two time periods to work properly.

Sounds confusing but it's really not. What I need is the following:

PWM Freq of 2.149 kHz and Duty at 58% for 200ms and then
PWM Freq of 1.517 kHz and Duty at 59% for 810ms.

Now I was going to do something simple like set up a timer to interrupt at 200ms and then reconfigure it.
Inside the ISR after I reconfigure the timer(to 200ms or 810ms), I was going to change the PWM as well.

Reading all the forums and the docs about CCU4 or CCU8, I think there is a much less CPU intensive way of doing this, but I just can't get my head around how this is done. I am working in Keil and not DAVE.

Can anyone enlighten me on how to do this? If I figure it out, I'll be back to answer my own question, but surely someone out here can help me out. 🙂

Thanks.
-stv Show Less