mem_test()...?

void send_data (void) {
  static const U8 rem_IP[4] = {192,168,0,100};
  U8 *sendbuf;

  if (wait_ack == __TRUE) {
    return;
  }
  if (mem_test (localm[NETIF_ETH].IpAdr, 0, 4) == __TRUE) {
    /* IP address not yet assigned by DHCP. */
    return;
  }
  if (bindex < 128) {
    sendbuf = udp_get_buf (512);
    for (i = 0; i < 512; i += 2) {
      sendbuf[i]   = bcount >> 8;
      sendbuf[i+1] = bcount & 0xFF;
    }
    udp_send (udp_soc, rem_IP, 1000, sendbuf, 512);
  }
}