W7500x Reference Manual Version1.1.0
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RTR[15:8]
0x0F
RCR (Retry Counter Register)
Address Offset : 0x6044
Reset value : 0x0000_0008
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RC[7:0]
R/W R/W R/W R/W R/W R/W R/W R/W
RCR configures the number of time of retransmission. When retransmission occurs as many as
‘RCR+1’, Timeout interrupt is issued (Sn_IR[TIMEOUT] = ‘1’).
When RCR is not ‘0x0000_0000, RCR is used to configure the timeout period of all socket.
When RCR is ‘0x0000_0000’, the timeout period of each socket could set by using Socket n
Retry Counter Register (Sn_RCR).
Ex) RCR = 0x0007
RC[7:0]
0x07
The timeout of WZTOE can be configurable with RTR and RCR. WZTOE has two kind timeout
such as Address Resolution Protocol (ARP) and TCP retransmission.
) retransmission timeout, WZTOE
automatically sends ARP-request to the peer’s IP address in order to acquire MAC address
information (used for communication of IP, UDP, or TCP). While waiting for ARP-response from
the peer, if there is no response during the configured RTR time, a temporary timeout is
occurred and ARP-request is retransmitted. It is repeated as many as ‘RCR + 1’ times. Even
after the ARP-request retransmissions are repeated as ‘RCR+1’ and there is no response to the
ARP-request, the final timeout is occurred and Sn_IR(TIMEOUT) becomes ‘1’. The time of final
timeout (ARP
TO
) of ARP-request is as below.
𝐴𝑅𝑃
𝑇𝑂
= (𝑅𝑇𝑅 × 0.1𝑚𝑠) × (𝑅𝐶𝑅 + 1)