NMEA SEATALK AGAIN

[jfkal]

Starting a new thread with thanks to all the input on the previous one FLUXGATE BLUES. I uderstand that I better redesign the way I am doing the linkup.
Some questions I do have still before a have a go at it.
1. When controling an Autopilot through the PC software; does the AP feedback anything to the PC or is it a oneway comm's only downstream from PC to the AP?

2. Does an Autohelm 4000 would respond to NMEA Wind data presented at its NMEA in port? If so I could decouple the AP from the Seatalk bus making live much easier.


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[qsiv]

I'm willing to be corrected - but my understanding is that all the pilot understands is CTS, and gives no fedback.

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[Guest]

On the Group :: GPSnavigator --- we are trying to solve this one also ......... basically as I have Autohelm tillerpilots that need connection to PC .......

May be worth looking at my post : Autohelm AH800 xxxxxxxx below ...

GPS Group address : http://groups.yahoo.com/group/gps-navigator/

You're welcome to join up .... it's free !



<hr width=100% size=1>Nigel ...
Bilge Keelers get up further ! I only came - cos they said there was FREE Guinness !

 

[Guest]

seems logical as why would AP need to talk to PC ... as the PC is just using the position vs route info off its own program and GPS ..... unless its necessary to count the clicks it sends ????

<hr width=100% size=1>Nigel ...
Bilge Keelers get up further ! I only came - cos they said there was FREE Guinness !

 

[jfkal]

Will have a look and come for the free guinness

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[bedouin]

As I understand (for the latest AH4000)

1. The Autohelm does not output any useful data; so there is no feedback to the PC

2. According to the manual it does respond to NMEA wind data - I intend to use this on my 4000 but haven't got round to it yet.

Certainly given the option, simulating the Wind info is probably easier than the GPS input; the Autohelm's response to GPS can be more sophisticated that its response to the wind (i.e in the GPS case it can use Cross Track error, and I presume it must compare Track to Bearing to Waypoint whereas for wind I think it can only use AWA).

NB I seem to remember that whatever you use the main steering is always against the fluxgate compass, and it only uses the external source to update the compass course once a minute or so.

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[bedouin]

As I understand (for the latest AH4000)

1. The Autohelm does not output any useful data; so there is no feedback to the PC

2. According to the manual it does respond to NMEA wind data - I intend to use this on my 4000 but haven't got round to it yet.

Certainly given the option, simulating the Wind info is probably easier than the GPS input; the Autohelm's response to GPS can be more sophisticated that its response to the wind (i.e in the GPS case it can use Cross Track error, and I presume it must compare Track to Bearing to Waypoint whereas for wind I think it can only use AWA).

NB I seem to remember that whatever you use the main steering is always against the fluxgate compass, and it only uses the external source to update the compass course once a minute or so.

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[Aeolus_IV]

Have got AH4000+ tracking wind instruments through NMEA interface - seems to work OK. Used it for hours like this between Eastbourne and the Solent a few months ago, close hauled it only "tacked" us accidentally once when the wind shifted too quickly.

Don't know about how often it checks the wind direction - just pleased it worked.

Jeff.

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