[Cause]
There were too many errors, and the circuit boards did not communicate with the network.
[Countermeasure]
Check that the board and device baud rates are the same. Check that power is connected to the DeviceNet network. Check the network wiring, including terminating resistors. Press the RESET key on the teach pendant. If the problem cannot be resolved, try removing devices from the network one at a time. Press the RESET key each time a device is removed. Once the board is online, check the settings of the disconnected device and the parameters in its device definition.