Hello,
Could somebody please help me with my problem in setting up a TCP client.
The code is as posted below.
I call the TCPConnection_start before i go into the main loop, which
initializes the connection. Then i call the TCP_send periodically( to send
some ADC values).
When my server opens a connection on Port 7 and I run my program it works
fine and the ADC values are sent. However sometimes it just goes into a hard
fault handler. Could someone please let me know where i am wrong?
void TCPConnection_start(void)
{
struct ip_addr DestIPaddr;
/* create new tcp pcb */
pcb = tcp_new();
if (pcb != NULL)
{
IP4_ADDR( &DestIPaddr, DEST_IP_ADDR0, DEST_IP_ADDR1, DEST_IP_ADDR2,
DEST_IP_ADDR3 );
/* connect to destination address/port */
tcp_connect(pcb,&DestIPaddr,DEST_PORT,TCPConnection_Established);
}
}
/**
* @brief Function called when TCP connection established
* @param tpcb: pointer on the connection contol block
* @param err: when connection correctly established err should be ERR_OK
* @retval err_t: returned error
*/
static err_t TCPConnection_Established(void *arg, struct tcp_pcb *pcb, err_t
err)
{
if (err == ERR_OK)
{
/* allocate structure es to maintain tcp connection informations */
es = (struct echoclient *)mem_malloc(sizeof(struct echoclient));
if (es != NULL)
{
es->state = ES_CONNECTED;
es->pcb = pcb;
}
}
}
void TCP_send(void)
{
uint32_t (*ptr)[3]; // pointer to the ADC_TDstamped_SRAM array.
#ifdef UserButton_InteruptFor_ADCConversion
sprintf((char*)data, "Potentiometer value is, %d\n",
ADC3ConvertedValue);
/* allocate pbuf */
es->p_tx = pbuf_alloc(PBUF_TRANSPORT, strlen((char*)data) ,
PBUF_POOL);
if (es->p_tx)
{
/* copy data to pbuf */
pbuf_take(es->p_tx, (char*)data, strlen((char*)data));
/* send data */
TCPData_send(pcb,es);
}
}
/**
* @brief function used to send data
* @param tpcb: tcp control block
* @param es: pointer on structure of type echoclient containing info on
data
* to be sent
* @retval None
*/
static void TCPData_send(struct tcp_pcb *pcb, struct echoclient * es)
{
struct pbuf *ptr;
err_t wr_err = ERR_OK;
while ((wr_err == ERR_OK) &&
(es->p_tx != NULL) &&
(es->p_tx->len <= tcp_sndbuf(pcb)))
{
/* get pointer on pbuf from es structure */
ptr = es->p_tx;
/* enqueue data for transmission */
wr_err = tcp_write(pcb, ptr->payload, ptr->len, 1);
if (wr_err == ERR_OK)
{
/* continue with next pbuf in chain (if any) */
es->p_tx = ptr->next;
if(es->p_tx != NULL)
{
/* increment reference count for es->p */
pbuf_ref(es->p_tx);
}
/* free pbuf: will free pbufs up to es->p (because es->p has a
reference count > 0) */
pbuf_free(ptr);
}
else if(wr_err == ERR_MEM)
{
/* we are low on memory, try later, defer to poll */
es->p_tx = ptr;
}
else
{
}
}
}