Thanks for the reply. I've tried it but found that it was not working out. I've used Modbus to send the new IP address from the client machine to the server board. Then I'm calling the relevant functions as suggested. I've confirmed that the new IP is set in the LWIP stack, by using the ST-LINK/V2 debugger. But the TCP/IP Raw socket server, which is the front end of the Modbus server is already set to the earlier IP address. I've done changes to it also, by making the IP Address global and tried to set it in the TCP Raw Socket server also, using this function call:
IP_ADDR4(&myIPADDR, new_ipaddr[0], new_ipaddr[1], new_ipaddr[2], new_ipaddr[3]);
Even this was not working out, most likely due to the "tpcb" knows only the previous IP Address. If I call the TCP server initialization again, it is disconnecting, freeing up the earlier "tpcb" and not preceding further. I've also tried with using a new "gnetif" and also the existing one. Either way it didn't work. I've copied the described functions below, please help.
/********** function for runtime ip address change start***********/
void LwIP-change-ip-cfg(uint8_t* ip_addr_array)
{
extern struct netif gnetif;
ip4_addr_t ipaddr;
ip4_addr_t netmask;
ip4_addr_t gw;
uint8_t IP_ADDRESS[4];
uint8_t NETMASK_ADDRESS[4];
uint8_t GATEWAY_ADDRESS[4];
IP_ADDRESS[0] = ip_addr_array[0];
IP_ADDRESS[1] = ip_addr_array[1];
IP_ADDRESS[2] = ip_addr_array[2];
IP_ADDRESS[3] = ip_addr_array[3];
NETMASK_ADDRESS[0] = 255;
NETMASK_ADDRESS[1] = 255;
NETMASK_ADDRESS[2] = 255;
NETMASK_ADDRESS[3] = 0;
GATEWAY_ADDRESS[0] = IP_ADDRESS[0]; //192;
GATEWAY_ADDRESS[1] = IP_ADDRESS[1]; //168;
GATEWAY_ADDRESS[2] = IP_ADDRESS[2]; //1;
GATEWAY_ADDRESS[3] = 1;
#ifdef USE_DHCP
ipaddr.addr = 0;
netmask.addr = 0;
gw.addr = 0;
#else
netif_set_down(&gnetif);
IP4_ADDR(&ipaddr, IP_ADDRESS[0], IP_ADDRESS[1], IP_ADDRESS[2], IP_ADDRESS[3]);
IP4_ADDR(&netmask, NETMASK_ADDRESS[0], NETMASK_ADDRESS[1] , NETMASK_ADDRESS[2], NETMASK_ADDRESS[3]);
IP4_ADDR(&gw, GATEWAY_ADDRESS[0], GATEWAY_ADDRESS[1], GATEWAY_ADDRESS[2], GATEWAY_ADDRESS[3]);
#endif
// add the network interface (IPv4/IPv6) without RTOS
//netif_add(&gnetif, &ipaddr, &netmask, &gw, NULL, ðernetif_init, ðernet_input);
// Set the new address parameters.
netif_set_addr(&gnetif, &ipaddr, &netmask, &gw);
// Registers the default network interface
netif_set_default(&gnetif);
// When the netif is fully configured this function must be called.
netif_set_up(&gnetif);
uint32_t local_IP = gnetif.ip_addr.addr;
uint8_t ip1 = local_IP & 0xff;
uint8_t ip2 = (local_IP >> & 0xff;
uint8_t ip3 = (local_IP >> 16) & 0xff;
uint8_t ip4 = (local_IP >> 24);
}
/**********function for runtime ip address change end ********/
/*********tcp raw socket server initialization start*********/
void tcp-server-init(void)
{
struct tcp_pcb *tpcb;
ip_addr_t myIPADDR;
err_t err;
/* 1. create new tcp pcb */
tpcb = tcp_new();
/* 2. bind _pcb to port 7 ( protocol) */
//IP_ADDR4(&myIPADDR, new_ipaddr[0], new_ipaddr[1], new_ipaddr[2], new_ipaddr[3]);
IP_ADDR4(&myIPADDR, 192, 168, 1, 70);
err = tcp_bind(tpcb, &myIPADDR, 502);
if (err == ERR_OK)
{
/* 3. start tcp listening for _pcb */
tpcb = tcp_listen(tpcb);
/* 4. initialize LwIP tcp_accept callback function */
tcp_accept(tpcb, tcp_server_accept);
}
else
{
/* deallocate the pcb */
memp_free(MEMP_TCP_PCB, tpcb);
}
}
/*********tcp raw socket server initialization end*********/
