change in udpPrepare, as suggested in issue #59

njh · Nov 1, 2012 · 49affe0 · 49affe0
1 parent 38ce251
commit 49affe0
Showing 1 changed file with 2 additions and 1 deletion.
diff --git a/tcpip.cpp b/tcpip.cpp
@@ -314,7 +314,8 @@ byte EtherCard::ntpProcessAnswer (uint32_t *time,byte dstport_l) {
 void EtherCard::udpPrepare (word sport, byte *dip, word dport) {
  setMACandIPs(gwmacaddr, dip);
  // see http://tldp.org/HOWTO/Multicast-HOWTO-2.html
- if ((dip[0] & 0xF0) == 0xE0) // multicast address
+ // multicast or broadcast address, https://github.com/jcw/ethercard/issues/59
+ if ((dip[0] & 0xF0) == 0xE0 || *((long*) dip) == 0xFFFFFFFF)
  EtherCard::copyMac(gPB + ETH_DST_MAC, allOnes);
  gPB[ETH_TYPE_H_P] = ETHTYPE_IP_H_V;
  gPB[ETH_TYPE_L_P] = ETHTYPE_IP_L_V;