| lwIP
    2.1.2
    Lightweight IP stack | 
| Macros | |
| #define | LWIP_ICMP 1 | 
| #define | ICMP_TTL IP_DEFAULT_TTL | 
| #define | LWIP_BROADCAST_PING 0 | 
| #define | LWIP_MULTICAST_PING 0 | 
| #define ICMP_TTL IP_DEFAULT_TTL | 
ICMP_TTL: Default value for Time-To-Live used by ICMP packets.
| #define LWIP_BROADCAST_PING 0 | 
LWIP_BROADCAST_PING==1: respond to broadcast pings (default is unicast only)
| #define LWIP_ICMP 1 | 
LWIP_ICMP==1: Enable ICMP module inside the IP stack. Be careful, disable that make your product non-compliant to RFC1122
| #define LWIP_MULTICAST_PING 0 | 
LWIP_MULTICAST_PING==1: respond to multicast pings (default is unicast only)