CTI 2572-B / 2500C-2572-B Installation and Operation Manual 33
Offset 9-10 IP Address of Default Gateway/Router - This identifies the address of the gateway to which a
packet with a destination IP address that is not on this module’s IP subnet will be sent.
Offset 8 contains the high 16 bits of the address and Offset 9 contains the low 16 bits. An
address greater than 223.255.255.255 (DFFF FFFF hex) will return an error. If you do not
have a gateway/router on your network, set this to 0.0.0.0 (0000 0000 hex).
Offset 11 Unused- This word is not used by the 2572-B module.
Offset 12-13 Subnet Mask - Specifies the subnet mask assigned to this network. Offset 12 contains the
high 16 bits of the mask and Offset 13 contains the low 16 bits. If offset 12 and 13 contain a
value of 0, then the subnet mask will default to the standard for the IP address class. A
subnet mask must contain all 1’s in the network portion of the IP address and must allow at
least 2 bits of host address. In addition, the subnet mask cannot be set so that the derived
host address is 0 or a broadcast address (all bits set to 1). See APPENDIX D. IP ADDRESS
INFORMATION.
Offset 14-15 IP Multicast Receive Address – If you want the module to receive multicast data, enter the
multicast address that you want the module to listen to. The valid range of multicast
addresses is 224.0.0.34 through 239.255.255.255. Before choosing a multicast address, see
APPENDIX D. IP ADDRESS INFORMATION for more information about the use of multicast
addresses.
NOTE:
When you trigger the Start Network Services command while the command block contains invalid
data, the 2572-B will return an error code and then halt. To recover, you must correct the
command block entry and restart the module.
When you are setting up the various IP addresses and subnet mask, you should set up your PLC programming
software to display the words in hexadecimal. Then you can enter each byte of the dotted notation
individually. For example, if the IP address were 198.35.34.10, you could enter the first word as hex C623
where the high byte (C6) is the hex equivalent of decimal 198 and the low byte (23) is the hex equivalent of
decimal 35. Similarly, you would enter the second word as hex 220A. See the following illustration.
Figure 6. Representing IP Address in Hexadecimal Format
To Next Page
Loading...