System overview
Output terminals
The R5 AIS Junction Box contains terminals with the AIS serial output.
One of the two highlighted output terminals can be used. Always make sure that the initially connected listeners receive the AIS signal.
Terminal | Name |
P12 (ECDIS) | TX-B |
P12 (ECDIS) | TX-A |
P19 (PILOT PORT) | TX-B |
P19 (PILOT PORT) | TX-A |
Parallel connection
The installation manual does not give full specifications about the output load. However, it does indicate the type of RS-485/RS-422 transceiver: DS89C21TM.
The DS89C21TM datasheet does not specify the number of allowed parallel receivers, but it states that it meets the requirements of the TIA/EIA-422-A standard.
The TIA/EIA-422-B (formerly RS-422-A) standard states, in point 5.2, that at least 10 receivers can be connected in a parallel (multi-drop) configuration.
