[CA] [CA11] A75, RL70C, problem with Goto Waypoint

[dmclennan]

I'm troubleshooting a very strange problem with my Raymarine RL70C and A75 chartplotters, networked together. It appears the A75 is sending the Goto Waypoint/Cursor even after the Goto is cancelled on the RL70C. The symptoms are on the RL70C: (1) select Goto waypoint/cursor, (2) select Cancel Goto. On the RL70C the Goto is cancelled and then immediately resumes. There's no way to cancel the Goto - it always reactivates the previous Goto Waypoint/Cursor.

The RL70C is our main chartplotter w/radar and chart chips for our cruising area. Earlier this year I installed an new EV-400 autopilot, along with a SeaTalk NG backbone. The A75 is mounted below. I was hoping it would display chartplotter and instrument display. The A75, EV400, EV1, i70,... make the SeaTalk NG network (works great). I also have a SeaTalk to SeaTalk NG bridge to connect the legacy SeaTalk instruments and the RL70C. GPS feeds SeaTalk NG which is properly displayed on both the A75 (SeaTalk NG), i70 (SeaTalk NG) and RL70C (SeaTalk).

If I disconnect the A75, this problem goes away. Reconnecting the A75, the problem resumes. I've changed the A75 'Data Sources', selecting the dedicated instruments. There's no way to turn-off the A75's as master controller for the SeaTalk NG network.

This appears to be a timing issue between the RL70C and the A75. The RL70C sends the Stop Goto. This is translated from SeaTalk to SeaTalk NG. The A75 gets the Stop Goto; meanwhile, the A75 resends the Goto (or PNG still in network), which is sent back to SeaTalk. The RL70C sees the Goto and resumes. The A75 never resends the Stop Goto -or- this is a bug in the Lighthouse software.

I've updated all the firmware to latest version. The only thing I can do to make the RL70C work properly is disconnect the A75.

Are there any advanced or dealer only settings that would put the A75 into a read-only mode? I don't want it to control the autopilot, waypoints, gotos, etc. just display boat's position on the chart. Ideally, if possible, I'd like to use the A75 to display the boat's data (GPS, wind, speed,....).

Any other suggestions for making the A75 work in my environment? Otherwise, I'll need to disconnect the A75's STNG cable and use its internal GPS for chart display.

Thanks,
Don

[Chuck - Raymarine - Moderator]

Welcome to the Raymarine Forum Don,

When the C/E-Series Classic MFDs were introduced, customers would sometimes attempt to interface them to the same SeaTalk bus that a hsb/hsb2/SL Pathfinder Series Display had been interfaced to ... the results were the same as those which had been reported by you. I have tested this scenario within a system featuring an a/c/e-Series MFD (v19.03) which has been interfaced to a hsb2 Pathfinder Series RL70CRC (v4.11) and a SeaTalk to SeaTalkng Converter (v2.03). It does take several seconds for a Go To command initiated and later cancelled on the a/c/e-Series MFD to be cancelled on the hsb2 Pathfinder Series RL70CRC. Go To commands initiated on the hsb2 Pathfinder Series RL70CRC (whether or not any have been previously commanded by the a/c/e-Series MFD) are automatically cancelled within seconds of their initiation. Unfortunately, this appears to be a limitation of interfacing hsb/hsb2/SL Pathfinder Series Displays to the generations of MFDs which followed.

An alternative means of data bridging may be advised. If the a75 MFD had featured a NMEA 0183 communications interface, then this interface would have been suggested. In this case, you may want to consider interfacing these two products to one another via another means ... specifically, via a programmable NMEA 2000 to NMEA 0183 interface (may require double adaptation NMEA 2000 to NMEA 0183 and then a programmable NMEA 0183 interface ... where one may configure which NMEA 0183 sentences will be enabled). Otherwise, it would be recommended that the hsb/hsb2/SL Pathfinder Series Display not be simultaneously operating within a network which additionally features an a/c/e-Series MFD (i.e. one of these devices will always be switched OFF). Alternatively, the hsb/hsb2/SL Pathfinder Series Display or a/c/e-Series MFD should be disconnected from the network.

[dmclennan]

Chuck,
Thanks for the reply, though not what I was hoping.

To clarify, the RL70C is the only unit to issue the Goto and navigation commands. In my case, the A75 is display only. The behavior is a Goto is initiated on the RL70C. Later, the Goto Stop is issued on the RL70C. The RL70C shows the stop (soft keys show Goto...). About a second later, the RL70C Goto is reactivated and the softkeys change back to active Goto. There's no way to cancel the Goto on the RL70C and it gets very confused.

This is all Raymarine equipment and from your description seems like a known deficiency. Aside from this behavior, the two chartplotters work very well together. In fact, I'm impressed with the integration and backwards compatibility.

I'm surprised you are suggesting another programmable interface, essentially to filter the NMEA 0183 sentences sent to the A75. That would require yet another component to be added to the network. I would have thought the A75 has features to enable/disable SeaTalk NG PGNs. Disabling the send navigation PGNs would solve this problem.

I will think about interfacing NMEA 0183 to the A75 or disconnecting the A75 from the network (defeats data features I was planning at the nav-station). I was hoping there are 'advanced' settings on the A75 to enable/disable PGNs, there's a workaround or Raymarine would correct this known software bug.

Thank you
Don

[Chuck - Raymarine - Moderator]

Don,

Q. I was hoping there are 'advanced' settings on the A75 to enable/disable PGNs, there's a workaround or Raymarine would correct this known software bug.
A. Unfortunately, the MFDs which followed the hsb/hsb2/SL Pathfinder Series Displays differed in handshake associated with navigational commands. As indicated within my initial response, this limitation in the hsb/hsb2/SL Pathfinder Series Displays was identified in the first generation of MFDs which followed (i.e. the C-Series Classic MFDs) ... and these systems both relied on SeaTalk communications. This not indicative of a bug, but a change in design. Four generations of MFDs have now been produced since the hsb/hsb2/SL Pathfinder Series Displays were retired and there will unfortunately be no future software updates to the software of the hsb/hsb2/SL Pathfinder Series Displays. Given the very limited number of such mixed systems, it would be challenging to build a business case to address such mixed systems. Within systems featuring more recent product designs such mastership features are not addressed by switching PGNs ON/OFF but by selecting the Data Sources which will be used by the system's devices. Unfortunately, your older equipment does not support this feature.

[dmclennan]

Thank you,
Don

[Chuck - Raymarine - Moderator]

You're welcome.