diff --git a/demos/ARM7-AT91SAM7X-LWIP-GCC/lwip/lwipthread.c b/demos/ARM7-AT91SAM7X-LWIP-GCC/lwip/lwipthread.c
index bb9f8ae5b..d89ab25ee 100644
--- a/demos/ARM7-AT91SAM7X-LWIP-GCC/lwip/lwipthread.c
+++ b/demos/ARM7-AT91SAM7X-LWIP-GCC/lwip/lwipthread.c
@@ -220,7 +220,7 @@ static err_t ethernetif_init(struct netif *netif) {
 /**
  * @brief LWIP handling thread.
  *
- * @param[in] p not used
+ * @param[in] p pointer to a @p lwipthread_opts structure or @p NULL
  * @return The function does not return.
  */
 msg_t lwip_thread(void *p) {
@@ -238,10 +238,25 @@ msg_t lwip_thread(void *p) {
   ip_init();
   tcpip_init(NULL, NULL);
 
-  /* TCP/IP parameters.*/
-  LWIP_IPADDR(&ip);
-  LWIP_GATEWAY(&gateway);
-  LWIP_NETMASK(&netmask);
+  /* TCP/IP parameters, runtime or compile time.*/
+  if (p) {
+    struct lwipthread_opts *opts = p;
+    if (opts->macaddress) {
+      unsigned i;
+
+      for (i = 0; i < 6; i++)
+        thisif.hwaddr[i] = opts->macaddress[i];
+      macSetAddress(&ETH1, thisif.hwaddr);
+    }
+    ip.addr = opts->address;
+    gateway.addr = opts->gateway;
+    netmask.addr = opts->netmask;
+  }
+  else {
+    LWIP_IPADDR(&ip);
+    LWIP_GATEWAY(&gateway);
+    LWIP_NETMASK(&netmask);
+  }
   netif_add(&thisif, &ip, &netmask, &gateway, NULL, ethernetif_init, tcpip_input);
 
   netif_set_default(&thisif);
diff --git a/demos/ARM7-AT91SAM7X-LWIP-GCC/lwip/lwipthread.h b/demos/ARM7-AT91SAM7X-LWIP-GCC/lwip/lwipthread.h
index fe939a178..7e001ddd1 100644
--- a/demos/ARM7-AT91SAM7X-LWIP-GCC/lwip/lwipthread.h
+++ b/demos/ARM7-AT91SAM7X-LWIP-GCC/lwip/lwipthread.h
@@ -102,6 +102,16 @@
 #define LWIP_IFNAME1            's'
 #endif
 
+/**
+ * @brief Runtime TCP/IP settings.
+ */
+struct lwipthread_opts {
+  uint8_t       *macaddress;
+  uint32_t      address;
+  uint32_t      netmask;
+  uint32_t      gateway;
+};
+
 extern WORKING_AREA(wa_lwip_thread, LWIP_THREAD_STACK_SIZE);
 
 #ifdef __cplusplus