LOWPAN_FRAG1_HEAD_SIZE 176 net/ieee802154/6lowpan/tx.c frag_len = round_down(payload_cap - LOWPAN_FRAG1_HEAD_SIZE - LOWPAN_FRAG1_HEAD_SIZE 183 net/ieee802154/6lowpan/tx.c LOWPAN_FRAG1_HEAD_SIZE, 0,