On power up each target board will first display the version number of the firmware in 1st digit on the left, It then will identify their location ID in the second and the third. Any board that is showing “888” has failed and should be replaced. Any board that the 1st digit remains on after the rest of the displays in the game clear indicates no communication to that board.
Both RJ45 Ports are identical. Either can be used for in or out communications. A coupler could be used to diagnose network issues if needed to eliminate the target board completely in the chain. The communication break should be between the last seen board shown in yellow or green and the next shown in red when in diagnostic mode. There is an extra 20’ Cat 5 cable included for finding com errors