How to receive data over ethernet using LWIP, UDP

Mbed OS
,
1

Im trying to send data to and from my computer and an STM32H745 over ethernet using LWIP and UDP. I have successfully configured the card and right now i can send data from the card to a python script running on the computer. However i dont understand how udp_recv works lwIP: UDP (nongnu.org) or how to recieve data with udp on lwip in general, and i cant find examples that do what i want to do. Where is the data being recieved? Should i even use udp_recv?

Below is the main code, just for refference.

const char* message = "a";

HAL_GPIO_TogglePin(GPIOE, GPIO_PIN_1); // orange

ip_addr_t PC_IPADDR;
IP_ADDR4(&PC_IPADDR, 192, 168, 1, 200);

u16_t port = 8000;

struct udp_pcb* my_udp = udp_new();

struct pbuf* udp_buffer = NULL;

/* Infinite loop */
for (;; )
{
	MX_LWIP_Process();
	HAL_GPIO_TogglePin(GPIOE, GPIO_PIN_1); // orange
	HAL_Delay(1000);

	udp_buffer = pbuf_alloc(PBUF_TRANSPORT, strlen(message), PBUF_RAM);
	if (udp_buffer != NULL)
	{
		memcpy(udp_buffer->payload, message, strlen(message));
		udp_sendto(my_udp, udp_buffer,&PC_IPADDR, port);
		pbuf_free(udp_buffer);
	}

	//udp_recv (struct udp_pcb *pcb, udp_recv_fn recv, void *recv_arg)

}

Any help is greatly appreciated!

2

Hello,

this forum is about MbedOS and related things.
So if you want to use MbedOS (it also use LWIP) then just visit its docs UDPSocket - API references and tutorials | Mbed OS 6 Documentation, owerwhise you probably need to find another place.

BR, Jan