diff --git a/software/include/net/microudp.h b/software/include/net/microudp.h
index 79a1b0e58..f9b339800 100644
--- a/software/include/net/microudp.h
+++ b/software/include/net/microudp.h
@@ -7,7 +7,7 @@
 
 typedef void (*udp_callback)(unsigned int src_ip, unsigned short src_port, unsigned short dst_port, void *data, unsigned int length);
 
-void microudp_start(unsigned char *macaddr, unsigned int ip);
+void microudp_start(const unsigned char *macaddr, unsigned int ip);
 int microudp_arp_resolve(unsigned int ip);
 void *microudp_get_tx_buffer(void);
 int microudp_send(unsigned short src_port, unsigned short dst_port, unsigned int length);
diff --git a/software/libnet/microudp.c b/software/libnet/microudp.c
index 8c6d62541..31bb5aaeb 100644
--- a/software/libnet/microudp.c
+++ b/software/libnet/microudp.c
@@ -350,7 +350,7 @@ static void process_frame(void)
 	else if(rxbuffer->frame.eth_header.ethertype == ETHERTYPE_IP) process_ip();
 }
 
-void microudp_start(unsigned char *macaddr, unsigned int ip)
+void microudp_start(const unsigned char *macaddr, unsigned int ip)
 {
 	int i;