diff --git a/main controller code/src/udp_client.c b/main controller code/src/udp_client.c
index 56fea9f..ac27548 100644
--- a/main controller code/src/udp_client.c	
+++ b/main controller code/src/udp_client.c	
@@ -5,7 +5,7 @@
 
 udp_client_t udp_client;
 
-static inline void handle_receive(struct pbuf *p, const ip_addr_t *addr, u16_t port)
+static inline void __not_in_flash_func(handle_receive)(struct pbuf *p, const ip_addr_t *addr, u16_t port)
 {
     if(p->len >= 2)
     {
@@ -18,22 +18,22 @@ static inline void handle_receive(struct pbuf *p, const ip_addr_t *addr, u16_t p
     pbuf_free(p);
 }
 
-static void udp_receive_callback(void *arg, struct udp_pcb *pcb, struct pbuf *p, const ip_addr_t *addr, u16_t port)
+static void __not_in_flash_func(udp_receive_callback)(void *arg, struct udp_pcb *pcb, struct pbuf *p, const ip_addr_t *addr, u16_t port)
 {
     udp_client_t *udp_client_received_data = (udp_client_t *)arg;
     handle_receive(p, addr, port);
 }
 
 // Default callback func
-static void default_message_callback(uint8_t *payload, uint16_t len, const ip_addr_t *addr, uint16_t port)
+static void __not_in_flash_func(default_message_callback)(uint8_t *payload, uint16_t len, const ip_addr_t *addr, uint16_t port)
 {
     printf("Received: packet=%d, len=%d from %s:%d\n", payload[0], len, ipaddr_ntoa(addr), port);
 }
 
 void udp_client_init(void)
 {
-    //udp_client.message_callback = udp_client_message_handler;
-    udp_client.message_callback = default_message_callback;
+    udp_client.message_callback = udp_client_message_handler;
+    //udp_client.message_callback = default_message_callback;
 
     udp_client.pcb = udp_new();
     if(udp_client.pcb == NULL)