Ethernet/IP bus interface for DIOLINE20 Vers. 1.00
Functional description
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4.3.3.1.2 Supported services
UCMM (Unconnected Message Manager)
Forward_Open
Get/Set Attribute
Get/Set Attribute All (only when specified explicitly)
4.3.3.2 TCP/UDP (IPv4)
This protocol is implemented compliant to the standard.
4.3.3.3 DHCP
This protocol is implemented compliant to the standard (RFC 2131, RFC 2132).
The module transmits a DHCP Discover in cycles until an IP address is assigned by the DHCP server.
The request is sent at the following times after DHCP initialisation:
0 s, 2 s, 4 s, 6 s, 8 s, 10 s, 12 s, … .
As soon as an IP address has been assigned, the Ethernet/IP stack reinitialises with the new IP
address (this can take anywhere from 10 s to 15 s).
The DHCP client behaves acc. to the following standard after the new IP address is assigned:
-
A Renew (unicast) is run after 50% of the lease time (=T1)
-
If the Renew fails then a Rebind to any server (broadcast) is run after 87.5% (=7/8) of the
lease time (=T2)
-
If even this Rebind fails then the stack looses its IP address and shuts down
The following behavior of the DHCP client should be noted regarding Renew and Rebind:
The responding DHCP server must run an ACK with the same IP address, otherwise the stack shuts
down! However, this can happen at any time during a Rebind, mainly if another DHCP server
responds. It might therefore be useful to only use one DHCP server.
4.3.3.4 BOOTP
This protocol is implemented compliant to the standard.
4.3.3.5 IGMP
This protocol is implemented compliant to the standard.
4.3.3.6 ICMP
This protocol is implemented compliant to the standard.
