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Server Hardware for openplotter?
(2020-05-06, 11:20 AM)glowntiger Wrote: what kind of autopilot? NMEA0183 V1 or older ( Means RS422 or toggling 12V??

Hi Thomas, I should also run my old Autohelm 1000, but it only has the Seatalk1 output and not nmea. I hope that as soon as you can you can put together a Setalk1-nmea183 bidirectional card to add to your MSC.  Smile Cool
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(2020-05-06, 11:20 AM)glowntiger Wrote: what kind of autopilot? NMEA0183 V1 or older ( Means RS422 or toggling 12V??

I try to interface a Raytheon Autohelm 300, it uses Seatalk1 for all sensors but also features an NMEA0183 interface in/out for most of the data I want to send and receive.

(Attached manual pdf at page 70)

It specifies in the Service manual that I've gotten hold of that NMEA in and out is a "Irregular train of 12V pulses" at + and 0V at -.
That sounds distrubing... probably v1 then?

However the input is described as NMEA Out + and -, which for me would point to it being differential, but service manual says otherwise...

It has to be possible to convert this 12/0 into 5+/5- with some basic electronics, right? Perhaps even on the MCS board for me to do?
Jeanneau Sun Odyssey 42.2 - All Openplottered and hooked up on online.
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(2020-05-06, 09:15 PM)flybob Wrote:
(2020-05-06, 11:20 AM)glowntiger Wrote: what kind of autopilot? NMEA0183 V1 or older ( Means RS422 or toggling 12V??

I try to interface a Raytheon Autohelm 300, it uses Seatalk1 for all sensors but also features an NMEA0183 interface in/out for most of the data I want to send and receive.

(Attached manual pdf at page 70)

It specifies in the Service manual that I've gotten hold of that NMEA in and out is a "Irregular train of 12V pulses" at + and 0V at -.
That sounds distrubing... probably v1 then?

However the input is described as NMEA Out + and -, which for me would point to it being differential, but service manual says otherwise...

It has to be possible to convert this 12/0 into 5+/5- with some basic electronics, right? Perhaps even on the MCS board for me to do?

Hi flybob,
yes this is an old V1 standard... You can read it with the MCS but not send to it because the MCS sends in RS422 format.
For Reading you can wire as in appended descriptet.
   
It is possible that signalk can´t parse this because some older devices uses a 00 character at the beginning.
We worked on it... ;-)
Mor you can find here:
https://www.segeln-forum.de/board194-boo...ost2156757
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(2020-05-08, 06:31 AM)glowntiger Wrote:
(2020-05-06, 09:15 PM)flybob Wrote:
(2020-05-06, 11:20 AM)glowntiger Wrote: what kind of autopilot? NMEA0183 V1 or older ( Means RS422 or toggling 12V??

I try to interface a Raytheon Autohelm 300, it uses Seatalk1 for all sensors but also features an NMEA0183 interface in/out for most of the data I want to send and receive.

(Attached manual pdf at page 70)

It specifies in the Service manual that I've gotten hold of that NMEA in and out is a "Irregular train of 12V pulses" at + and 0V at -.
That sounds distrubing... probably v1 then?

However the input is described as NMEA Out + and -, which for me would point to it being differential, but service manual says otherwise...

It has to be possible to convert this 12/0 into 5+/5- with some basic electronics, right? Perhaps even on the MCS board for me to do?

Hi flybob,
yes this is an old V1 standard... You can read it with the MCS but not send to it because the MCS sends in RS422 format.
For Reading you can wire as in appended descriptet.

It is possible that signalk can´t parse this because some older devices uses a 00 character at the beginning.
We worked on it... ;-)
Mor you can find here:
https://www.segeln-forum.de/board194-boo...ost2156757

Great, when i read about the different NMEA versions I also thought of wiring it like that.
Will change the wiring and hopefully get some data in then at least.

About sending data to the plotter, would it not be possible to do similar? Using - as GND and + as Signal, the differential voltage between the two should be enough for the Autopilot to interpret but perhaps he will get angry if I send negative voltages at the input...? 

Another option would perhaps be to make a proper conversion of the differential signal to single ended, is that the main difference between the two?
Jeanneau Sun Odyssey 42.2 - All Openplottered and hooked up on online.
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If signalk can´t read the data, you can check the incomming data with a little python script (see attached)
You must edit the Port an baudrate... ;-) (be sure that the Port isn´t in use by any other application)
   
Code:
import serial


ser = serial.Serial(
              port="/dev/ttySC0",
              baudrate = 4800,
              parity=serial.PARITY_NONE,
              stopbits=serial.STOPBITS_ONE,
              bytesize=serial.EIGHTBITS,
              timeout=1
          )

if ser.is_open == 1:
   ser.close()
ser.open()


print (ser.get_settings)
   

while 1:
   try:
       x = ser.readline()
       print(x)
   except (OSError, serial.serialutil.SerialException):
       print("no data")

I think that did not work. V1NMEA toggles between 0-12V. RS422 works with differetial voltage. The Output produces an absolute voltage rating to gnd from 0-3,3V. Means in standby both A/B Pegel have ca 1,7V. If sending both channels toggles between 0-3,3V in different pegel. The NMEAV1 need 0-12V. I think the NMEAV1 In of the other device interpret it as always 0. Don´t now wehre there is the trewshold....
The recieving works because we use an active biasing. Means we pull A to 3,3V and B (B-A=<0) to gnd with an internal resistor. So you get a logical 0. If you now only pull B to 12V B-A=>0 and you get an logical 1.
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There we go!

[dollar]IIHDM,180.,M
[dollar]IIHDT,181.,T
[dollar]IIHDG,180.,,,01.,E
[dollar]IIBWC,,,,,,,T,,M,,N,

I catch all the dollarsign hex's and also try to find nulls, seems like i don't get the nulls at least.
y = x.replace("\x00", "[null]")
z = y.replace("\x24", "[dollar]")

Now if only the Autopilot would send out the rest of the data he got over Seatalk (Wind, Depth, Speed etc) I would be happier...
Too bad I'm away from the boat while coding, can't press that "auto" button on the autopilot to make it talk about XTE etc!
It's always on my local network through VPN using the 4g modem on board, convenient to keep working from home.

If I turn off validation of checksum then SignalK gets the data.

A differential to single ended module could help me interface the Autopilot? Making the RS422 into 0/12v, correct?
Jeanneau Sun Odyssey 42.2 - All Openplottered and hooked up on online.
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Hy flybob,
sounds good. Seems realy you get no 00... At some devices this happens. not at all...
Normaly he do so? If you connect wind the autopilot also push out this sentence to NMEA?
Yes you need a modul to convert the differential to 0/12V don´t know if there is something ready on the market?
I make a add on board for Seatlak and NMEAV1 but I need a while... At the Moment I work on a digital Input/output board...
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A ST/NMEA board would be highly sought after, hard to find anything not too expensive.
I don't have a wind indicator at all actually Smile

I won't get any relevant data from the sensors using Nmea, manual says that autopilot will only output these sentences on Nmea interface:
Cross Track Error XTE
Bearing to Waypoint BWC
Distance to Waypoint BWC
Waypoint Number BWC
Latitude and Longitude GLL
Magnetic Heading HDG, HDM, HDT
True Heading HDT
Locked Autopilot Heading HSC
Course Over Ground VTG
Speed Over Ground VTG
Fix/No Fix GLL

So needs either ST/STng converter, or ST/NMEA, to get instrument data into OpenCPN.

Regarding conversion to 12v, the MAX485 circuit converts rs422 to rs485 and also up to 12v. Easy peasy.
https://www.ebay.com/itm/MAX485-TTL-Schn...SwyuZdK6o8
Jeanneau Sun Odyssey 42.2 - All Openplottered and hooked up on online.
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Hello,
with pleasure I finished the HD configuration of RPI / HAT / MCS and I like it and it works.
Now I ask: in the meantime, I would like to make a Raymarine I60 Wind communicate with the Openplotter / SK system via MCS CAN-Bus, but I cannot find documentation (MCS?) On how to set the software side. How to communicate I60-MCS-RPI- openplotter-SK.
Can I have easily interpretable help?
Thanks.

Nicola L.
Comet 1000 - Openplotter under construction
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Hi Nicola,
The setup for the can(nmea2000) must be done in the can app of openplotter. There you must setup the mcp2515. Here is a video:
https://m.youtube.com/watch?v=w4nGNWhy_9c
It's in german but beginning at 2:45 you see how to configure the can. There you also see the incoming data with candump.
At the first entry in this thread you find the most instructions.... ;-)
If you need further help, let me know....
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