User Manual

CH.5 SUP0740-07
11/30/2009 Page 30 of 98 # 958
Ping Time Reg: Enter an OCS Register reference (such as %R202) to indicate which 32-bit
OCS register will be written with the Ping Echo Request / Response round-trip time (in
milliseconds).
Ping Timeout: Enter a number between 100 and 100,000 for how often (in milliseconds) the
Ethernet Module should send Ping Echo Requests.
5. Click OK to accept the new ICMP Configuration.
5.3 ICMP Operation
To start Ping Echo Requests, use Ladder Code, User Screens or Cscape Data Watch to write an
IP Address to the OCS register indicated by Ping IP Reg. To check the resulting Ping Echo
Response times, read the OCS register indicated by Ping Time Reg. If the round-trip time
exceeds the configured Ping Timeout (or if there is no response at all), the reported response
time will be -1.
To stop Ping Echo Requests, write 0.0.0.0 to the OCS register indicated by Ping IP Reg.
Note that ICMP protocol is active even when the OCS is not
in RUN mode. Therefore, when the
OCS is not
in RUN mode, User Screens and Cscape Data Watch can still be used to control and
monitor ICMP Pinging.