OpenCPN SIMRAD/LOWRANCE Radar Overlay PlugIn

[cowelld]

Hi Robbie,
The ranges capabilities of the three are 24 km. 36 km and 64 km so you have one difference there. The 3G/4G have dual range capabilites (which our plug-in doesn't currently use) and some other features.

The RI10 and RI11 vary only in that one uses SIMNET and the other NMEA 0183 for input. We haven't figured out what it does with the data since we don't need it. We don't send HDG data to the scanner. The documentation for the NSS7 requires a high HDG data rate for the RI unit if using NMEA 0183.

We use COG and HDG to determine the chart overlay feature. It's better if you have an electronic compass since GPS data can sometimes be erratic if your speed is low. (If you use OpenCPN with a GPS while docked you can sometimes see the boat icon hopping in small circles. That's a real nuisance if the plug-in believes there's a COG since it'll swing the radar image accordingly.) If no COG or compass then it's strictly a North Up display.

We don't do MARPA. It's too complicated and we're afraid of the liability.

Hasta,
Dave C

[RobbieW]

Thanks Dave,
I have a Raymarine S3G from which I should be able to derive a heading input at the data rate required by Navico (Simrad) devices, separate to a GPS derived COG. The S3G NMEA 0183 output should meet the heading requirement, the RI10 interface box seems to have the potential for mixing a heading input with the radar output - I'd need an AT10HD NMEA <-> Simrad interface box to feed heading input data into the RI10 though. The AT10HD seems to be bi-directional in that it would accept NMEA 0183 heading messages and output NMEA 2000/SIMNet equivalents.

Thats kind of what I was asking so your answer makes some sense that the plugin wouldnt use the heading data even if it were there.

So a follow on question is which of the several data ports defined by the Navico/Simrad interface might accept heading data if it were provided? If I can get heading data into OCPN, I can surely retransmit it on a defined data connection to a port that the scanner is listening to.

Regards ... Robbie

[Neptune's Gear]

Hi Robbie,
I too have a Simrad simnet system, and use 2 AT10 units for translation to NMEA0183. My compass is a Simrad RC42. This (via the AT10) provides heading info to Opencpn, and results in a very stable radar overlay, at standard NMEA 0183 speed (4800 Baud). What exactly do you hope to acheive by providing high speed heading data to the Radar??
And, the RI10 is not required. I don't have one, and it works fine...
Cheers
Matt

[BMD21]

Correct me if I'm wrong, but... The AIS overlay for OpenCCPN provides closest approach, etc, etc. At least it did something similar when I used the AIS receiver and OpenCPN in San Diego Bay.

What I getting at is that if you want MARPA functions, they're already available in OpenCPN for the cost (mine cost ~$100,) of an AIS receiver. As a matter of fact every YACHT in San Diego Bay had their AIS transmitter turned on, moving or not. I finally turned the AIS function off, but it's there.

Boris

[Hakan]

Originally Posted by RobbieW

...I dont think it matters which scanner I get from the Navico range, I suspect they all have the same firmware? Obviously the 3G and 4G are different though.

3G and former BR24 differs in capacity from 4G but both are to be supported by the br24radar_pi plugin. Canboat (Kees) nicely works to get the 4G support functional and for the moment it seems very close.

Being in Europe, they are all supplied with the RI10 interface box but I cant see thats relevant to an installation that will use only OCPN as its display?

Correct - For the connection to OCPN and the plugin no box is used. You only supply power and IP-network. The network connection is a RJ45 plug to your computer. (In Navico's installation manual it's for some reason called the US connection style.)

Have any of you got heading data out to the scanner to stabilise the output? Or am I misunderstanding something here - basically what connections are required to get the chart overlay to align.

OCPN, like any viewer, needs to have heading data from any other source, like a Fluxgate compass, to align the radar picture on the charts overlay. Without a compass only the stand alone function is possible.

Finally it looks like MARPA function is processed in the scanner which requires heading data. Does the BR24 plugin support MARPA function at present?

No - the scanner, or call in the antenna, don't calculates anything like that. That has to be done in the viewer and the br24radar_pi don't have that function.

Håkan

[RobbieW]

Originally Posted by BMD21

Correct me if I'm wrong, but... The AIS overlay for OpenCCPN provides closest approach, etc, etc. At least it did something similar when I used the AIS receiver and OpenCPN in San Diego Bay.

What I getting at is that if you want MARPA functions, they're already available in OpenCPN for the cost (mine cost ~$100,) of an AIS receiver. As a matter of fact every YACHT in San Diego Bay had their AIS transmitter turned on, moving or not. I finally turned the AIS function off, but it's there.

Boris

To an extent you are right, I'd have no problem with AIS Class A targets and that approach. Where I have a concern is with Class B, it would be nice to have some independent verification in bad vis that the Class B target is where it says it is - given the often slow update period for Class B. Its also the case that whilst 'all' Class A size targets will have AIS, nothing like all Class B size vessels do.

I have found a supplier offering an NSS8/3G scanner combo for little more than the cost of the scanner - thats the route I'm now following.

[RobbieW]

Originally Posted by Hakan

...No - the scanner, or call in the antenna, don't calculates anything like that. That has to be done in the viewer and the br24radar_pi don't have that function.

Håkan

Thats not the impression I've gained from Navico documentation and reading back on the gradar plugin thread. What I think happens is that the MFD identifies the MARPA target required to the scanner, the scanner then follows that target (and outputs TLL etc - I think, though this may be the Garmin unit).

That aside, does the BR24 plugin now support EBL and distance markers? ie old style radar tracking.

[rgleason]

Since knowledge is useful, some other parallel links

http://www.cruisersforum.com/forums/...pn-114842.html

http://www.cruisersforum.com/forums/...r24-97281.html

http://www.cruisersforum.com/forums/...in-123167.html

The Original for Garmin
http://www.cruisersforum.com/forums/...-79081-38.html

====
These are the GoFree PDF's which have information about tiers and network protocols.
GoFree Developer Toolkit - Simrad Marine Electronics

The pdf about the Web interface is interesting
UDP, Bonjour for Windows, etc.
The pdf about Tier 1 is also good
Talks about blocking out radar data stream so as not to overwhelm ships wifi.

[RobbieW]

Good News!
The kit has all arrived and been installed, now in the process of tidying up the installation hiding wires etc. I have a 3G Navico radome + the Simrad NSS8 MFD, also the RI10 & AT10 interface boxes.

Have already tried out the radar into OCPN by piggy backing the ethernet cable through a switch, so I'm getting dual disply on the MFD and laptop. At present the laptop is on a wired connection, looking at my router displays throughput is peaking around 70Mb/sec with the radar active. Thats more than 11g can do but should be within 11n's capability.

Wont be getting the HDM input to the MFD till later in the season, need an N2K bus, but I'll probably get it wired into the laptop soon - already tested but not since I downloaded the plugin.

More later but if theres anything I can try to trace, happy to see what can be done.

[Douwe Fokkema]

I am currently puzzling which radar to buy. It could be the Garmin, but the Simrad 3G seems more attractive. But the connection of the Simrad to OpenCPN seems a bit more complex, less proven. Is there any description on how to connect? Does the Simrad need on "ON" switch on the ethernet cable like the Garmin ? What is the IP configuration? Is this described somewhere? Thanks for your help.

Douwe

[Hakan]

I've BR24 installed in my boat and using the br24radar_pi plugin. If I'm correct the BR24 is issued before and replaced by the 3G. The 4G is more powerful and is also slightly different in how it's controlled.
The Navico(Simrad/Lowrance) type is very straightforward to connect. No special IP address handling. Just to connect the net cable and power. No extra hardware switch for stand by mode is needed, that's software controlled.
The plugin is still under it's final development by canboat (Kees) and cowell (Dave C) and some support by me and others. The status is that BR24 (and probably 3G) is working fine but 4G may have some minor issues to solve.
There's also a manual produced but not yet issued.
The latest plugin code is available on https://github.com/canboat/BR24radar_pi and a windows binary(dll) is here: opencpn-navico-radar-plugin.github.io this dll has a know strange behaviour when using OCPN beta 3.3.1713 and later but I've a temporary fix if needed.
In lack of the manual me and others can of course support when needed but this thread can help and also applicable parts of the "OpenCPN Radar Overlay PlugIn" thread where the Navico gadget initially was discussed before the found of this thread.
Håkan

[merrimac]

Originally Posted by Douwe Fokkema

I am currently puzzling which radar to buy. It could be the Garmin, but the Simrad 3G seems more attractive. But the connection of the Simrad to OpenCPN seems a bit more complex, less proven. Is there any description on how to connect? Does the Simrad need on "ON" switch on the ethernet cable like the Garmin ? What is the IP configuration? Is this described somewhere? Thanks for your help.
Douwe

Hoi Douwe,

Dat zou ik niet zeggen hoor. En als je naam iets zegt over waar je woont is dan heb je evt. (mijn) support om de hoek (Harns.)

--
Hi Douwe,

I don't want to speak for the Garmin plugin, but I'd say the Navico plugin is maturing quite rapidly the last 2 months. I re-implemented the controls so that they don't use as much space, and the radar image is quite good. We're still ironing out some issues with the guard zones, etc, but that doesn't preclude it being very useful already.

There is little information on IP settings because you don't need any. The radar and OpenCPN communicate using multicast, which does not rely on IP addresses. There is one snag: it doesn't work very well over wireless, as multicast is generally transmitted at the lowest possible rate (1 Mb/s). So as long as you have wired Ethernet connection set up between the two it will work. No ON switch is needed.

Groeten,
CANboat/Kees

[merrimac]

Originally Posted by Hakan

The status is that BR24 (and probably 3G) is working fine but 4G may have some minor issues to solve.
There's also a manual produced but not yet issued.
The latest plugin code is available on https://github.com/canboat/BR24radar_pi and a windows binary(dll) is here: opencpn-navico-radar-plugin.github.io

• There are no known 4G-specific issues. Several beta testers including myself use a 4G.
• I second the reference to https://github.com/canboat/BR24radar_pi. This is where we do all development and communication between the developers and testers for the plugin. If you have any issues it's best if you bring it up there.

[merrimac]

I fixed a whole ream of issues today, most related to guard zones and controls.

See github for a list of changes made.

The Windows DLL can be downloaded in binary format.

[deandavis1]

This is really awesome work. I know I've asked this before, but is there any chance someone with the skill set can compile Mac version of the plugin..... please