Posted on March 30, 2012 at 16:19
Hi everybody,
I want to
make
an Ethernet connection
between the stm32f4 discovery board and my computer. I use a DP83848 Ethernet Board (
http://www.wvshare.com/product/DP83848-Ethernet-Board.htm
) to the Ethernet Physical Layer.
I implement the LwIP TCP/IP stack on my board. And for the moment
I try to send
UDP
data
to the computer
from the card
.
I configure ethernet with the file stm32f4x7_eth_bsp.c. And when
I test
ping
between
my card and
the computer
it works
.
I create an function to send UDP Data :
void
udp_send_data(
void
)
{
struct
udp_pcb *ptel_pcb;
char
msg[]=
''testing''
;
struct
pbuf *p;
struct
ip_addr ipaddr;
/* Mise à jour de l'adresse IP du dest */
IP4_ADDR(&ipaddr, IP_DEST_ADDR0, IP_DEST_ADDR1, IP_DEST_ADDR2, IP_DEST_ADDR3);
ptel_pcb = udp_new();
udp_bind(ptel_pcb, &ipaddr, 1235);
//udp_recv(ptel_pcb, udp_echo_recv, NULL);
p = pbuf_alloc(PBUF_TRANSPORT,
sizeof
(msg),PBUF_RAM);
memcpy
(p->payload, msg,
sizeof
(msg));
udp_sendto(ptel_pcb, p, &ipaddr, 1234);
pbuf_free(p);
//De-allocate packet buffer
}
And I use it in the main program :
int
main(
void
)
{
/*!< At this stage the microcontroller clock setting is already configured to
168 MHz, this is done through SystemInit() function which is called from
startup file (startup_stm32f4xx.s) before to branch to application main.
To reconfigure the default setting of SystemInit() function, refer to
system_stm32f4xx.c file
*/
unsigned
int
i;
/* configure ethernet */
ETH_BSP_Config();
/* Initilaize the LwIP stack */
LwIP_Init();
/* UDP echoserver */
udp_echoserver_init();
/* Infinite loop */
while
(1)
{
/* check if any packet received */
if
(ETH_CheckFrameReceived())
{
/* process received ethernet packet */
LwIP_Pkt_Handle();
}
/* handle periodic timers for LwIP */
LwIP_Periodic_Handle(LocalTime);
Delay(100);
udp_send_data();
}
}
In this configuration this
data
are
sent in
UDP
but if remove the following code :
/* check if any packet received */
if
(ETH_CheckFrameReceived())
{
/* process received ethernet packet */
LwIP_Pkt_Handle();
}
/* handle periodic timers for LwIP */
LwIP_Periodic_Handle(LocalTime);
There aren't UDP Frame !!! So I don't understand UDP
protocol
:(
I look for
examples
of
simple
UDP connection
?
