Introduction and sending route to iNavX

[Antipole]

Greetings from a new OpenCPN user. I hope this is the right place to raise some queries. I will make them in separate posts to keep responses tidier but include my first two most crucial ones here. First a little background:

My yacht Antipole has an NMEA2000 network. I use an Apple MacBook as my main navigational system at the navigation station and an iPad running iNavX at the wheel station. For the last eight years the MacBook has been running the navigation program MacENC. This interfaces to the NMEA2000 network via USB and creates a WiFi network over which it sends navigational data to the iPad and iPhones running iNavX. This includes the current route. This is important, because, were the navigational system to fail, the MacBook to crash or run out of power, the iPad will continue to navigate according to the latest route using its own GPS.

MacENC has been great but, sadly, I must move on. It is no longer being developed and it is 32-bit only, so will not run under MacOS Catalina. Further, Fugawi has stopped providing charts for it. So I have been delighted to have discovered OpenCPN. My initial evaluation is that it looks good and flexible. I also like that it is not subject to the strictures of a single developer as for MacENC and iNavX.

I have installed an Actisense W2K-1 unit that gateways between my NMEA2000 and WiFi to replace this function of MacENC. OpenCPN and iNavX are receiving the ship’s navigational data fine via this new gateway.

Repeating AP and route data to iNavX

I have iNavX receiving UDP data and have OpenCPN transmitting AP data over UDP. This works to the extent that a goto waypoint and the cross-track error are being picked up by iNavX, albeit with delays I am unused to.

I also need to send the active route to iNavX using $GPWPL and $GPRTE sentences. The ‘Send to GPS’ button in the Route and Mark Manager seems to send to a serial port rather than via UDP. The manual says:
The feature “Send to GPS”, which appears in right click menus for waypoints and routes and in the Route Manager, is not linked to connections. The upload port does not even need to appear in the Datastream connections list. Its a completely separate concept. For this reason users must define a separate upload port, that is remembered by OpenCPN. The port can be changed by clicking the button in the Route Manager. I cannot see how to do this. [I am using OpenCPN v5.0.1]

Question 1: How can I get this data sent over UDP?

If I can get this working, there is still a serious problem - this is a one-time transmission. With MacENC, the current route is sent repeatedly using $GPWPL and $GPRTE sentences. With OpenCPN, if the navigator moves a waypoint or adds an extra one, perhaps to avoid a hazard, s/he must retransmit the route for it to be updated on the iPad at the wheel station. This is easily overlooked. Further, as it is being send over UDP the update might be lost. If I open iNavX on my iPhone from in my bunk to check on progress, I may not be seeing the latest route. This has the serious and dangerous situation whereby the navigator has updated the route in OpenCPN but the helmsman is unwittingly steering by an obsolete route.

Question 2: how can I ensure repeated automatic transmission of the current route and its waypoints to iNavX?

I hope to learn of solutions - thank you.

[GordMay]

Greetings and welcome aboard the CF, Antipole.