I have a TZT3 16, a Vesper Cortex, a 300 NavPilot, and an SCX20. I want to use the SCX20 for GPS, heading and other “location” PGN’s for both plotters and the NavPilot. I will also add a TZT3 12 within the month. Within this setup, how should I set up the device instancing? My confusion arises from comments on this forum that changing the device instance on the CP from zero can create an issue. However, if the device instance of the CP’s are zero, wouldn’t that cause their GPS readings to take precedence over the SCX20, regardless of what the SCX20 device instance is defined as? What is the proper setup for these four devices?
Specific question on device instance
- Thread starter Helmsman
- Start date
You should never have to change any of the Furuno MFD instance numbers unless trying to run with other chart plotter manufacturers on the bus. They all normally remain at zero. It is impossible for the Furuno MFDs to get instance conflicts with each other because of the software design where there is only one "Data Master" talking on the 2000 bus regardless of how many Furuno MFDs are installed.
I have never heard of an AIS unit looping data that it receives. That would be a question for vesper. It should only be putting out AIS PGNs as far as I know.
Here are the PGNs sent by the Cortex from the Garmin website. The depth would be an example of one being looped, I think. The HDG and COG are probably coming from the Cortex GPS antenna. I would prefer to use the SCX20 for those PGN’s and set them to be used by the MFD’s first from the SCX20 as described in post 2 above.
I can also set which Instrument provides PGN’s TO the Cortex per the Cortex instructions. I am not sure I want to turn off PGN’s coming from the Cortex. I would prefer to have them as alternates In case another sensor fails. Perhaps setting the device instance to 1 for the Cortex on the TZT3 16 will accomplish that.
Sent PGNs are either generated directly by the Cortex system or are translated from incoming 0183 sentences.
I can also set which Instrument provides PGN’s TO the Cortex per the Cortex instructions. I am not sure I want to turn off PGN’s coming from the Cortex. I would prefer to have them as alternates In case another sensor fails. Perhaps setting the device instance to 1 for the Cortex on the TZT3 16 will accomplish that.
Sent PGNs
Sent PGNs are either generated directly by the Cortex system or are translated from incoming 0183 sentences.
| PGN | Description | Translated from 0183 |
| 127233 | Man Overboard | |
| 127250 | Vessel Heading | HDG |
| 127258 | Magnetic Variation | |
| 128259 | Speed, water Referenced | VHW |
| 128267 | Water depth | DBT DPT |
| 129025 | Position (Rapid) | |
| 129026 | COG & SOG (Rapid) | |
| 129029 | GNSS Position | |
| 129038 | Class A Position | |
| 129039 | AIS Class B position | |
| 129040 | AIS Class B position extended | |
| 129041 | AIS Aids to Navigation | |
| 129539 | GNSS DOP’s | |
| 129540 | GNSS satellites in view | |
| 129794 | AIS Class A Static Voyage | |
| 129798 | AIS SAR Aircraft Position | |
| 129801 | AIS Addressed Safety | |
| 129802 | AIS Safety Related Broadcast | |
| 129809 | AIS Class B “CS” Static, Part A | |
| 129810 | AIS Class B “CS” Static, Part B | |
| 130306 | Wind data | MWD MWV |
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It isn't uncommon to see that happen with 2000 devices. Most require that you change it and then power cycle the device for the change to fix. Most Furuno devices are like that so I would expect the Vesper is the same way but I defer to their support as it isn't our product.
Thank you. It wouldn’t change after re-booting. I will see how it responds after assigning all the devices the way I want them. Will report back what I find. Appreciate the help.
