Data Sheet
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32
iEthernet 
W5200
0X1D  SOCK_LAST_ACK  In  case  of  Passive  closing,this  status  indicate  that  W5200 
waits  ACK  for  FIN  packet.  It  is  changed  to  SOCK_  CLOSED, 
when Timeout Interrupt occurs (Sn_IR(TIMEOUT)=‘1'). 
0x01  SOCK_ARP  This  status  indicates  that  ARP-request  is  transmitted  in 
order  to  acquire  destination  hardware  address.  This  status 
is  observed  when  SEND  command  is  performed  at  the 
SOCK_UDP  or  SOCK_IPRAW,  or  CONNECT  command  is 
performed at the SOCK_INIT.   
If  hardware  address  is  successfully  acquired  from 
destination  (when  ARP-response  is  received), it  is  changed 
to  SOCK_UDP,  SOCK_IPRAW  or  SOCK_SYNSENT.  If  it's  failed 
and ARPTO  occurs (Sn_IR(TIMEOUT)=‘1’), in  case of UDP or 
IPRAW  mode  it  goes  back  to  the  previous  status(the 
SOCK_UDP or SOCK_IPRAW), in case of TCP mode it goes to 
the SOCK_CLOSED. 
cf> ARP-process operates  at  the SOCK_UDP or  SOCK_IPRAW 
when  the  previous  and  current  values  of  Sn_DIPR  are 
different. If the previous and current values of Sn_DIPR are 
same, ARP-process doesn’t operate because the destination 
hardware address is already acquired. 










