Omron CJ1W-ETN21 - 04-2009 Operation Manual page 226

Command/Response Reference
Response Codes
IP Address (Response)
The local IP address set in the CPU Bus Unit System Setup for the Ethernet
Unit is returned in order starting from the leftmost bytes in hexadecimal. If the
local IP address set in the allocated words in the DM Area is enabled, 0.0.0.0
is returned.
Subnet Mask (Response)
The subnet mask set in the CPU Bus Unit System Setup for the Ethernet Unit
is returned in order starting from the leftmost bytes in hexadecimal.
Response code
0000 Normal
1001 Command too large
Section 7-3
Description
201