Raymarine's Micronet

[Gixer]

Hello,

Is there any third party device that will talk to Raymarine's Micronet?

I'm thinking of a one box solution for linking to my ipad rather than T122 and quark wi-fi device.

Any ideas?

 

[Mikedefieslife]

I don't think so. That would be awesome. The closest would be Raymarine's Micro-talk that is a Micro-net to NMEA2000 converter. Bear in mind that micronet tranducers will not work with a micronet display.

 

[Gixer]

Thanks,
I'm surprised Quark or Marine Electronics haven't come up with something. I guess the protocol is locked or something.

 

[prv]

I'm surprised Quark or Marine Electronics haven't come up with something. I guess the protocol is locked or something.

Seatalk1 is proprietary as well, but there are probably millions of devices out there using it, produced over thirty years or so. So there were people interested in reverse-engineering it, and a market for products using that knowledge.

TackTick instruments have always been a far, far smaller niche - and reverse engineering a radio signal needs extra skills and kit over a cabled serial link. So it could probably be done (assuming the data isn't actually encrypted, which I doubt) but it's not very surprising that it hasn't been.

Pete

 

[Gixer]

That's really interesting prv and makes sense now, thanks for the info.

 

[DAVAIS]

Quark A031 is able to convert the old Seatalk messages into NMEA 0183 and then output via WiFi. This is the way I am using now.

 

[prv]

Quark A031 is able to convert the old Seatalk messages into NMEA 0183 and then output via WiFi. This is the way I am using now.

I am cooking my dinner at the moment. I’m sure it will taste nice.

Pete

 

[Mikedefieslife]

Quark A031 is able to convert the old Seatalk messages into NMEA 0183 and then output via WiFi. This is the way I am using now.

Hmm, what does that have to do with Micronet though which is what the OP's instruments are? Micronet operates on 800-900mhz depending on where you are in the world. That is a long way from Wifi at 2.4 and 5ghz.

 

[Gixer]

Quark A031 is able to convert the old Seatalk messages into NMEA 0183 and then output via WiFi. This is the way I am using now.

Thanks for the response, I was trying to find out is there's something else I could use instead of a raymarine T122 and Quark A to get data to my ipad but it looks like there isn't.

 

[[163233]]

Micronet was developed when tacktick was distinct from Raymarine so the protocol probably doesn't resemble Raymarine's other proprietary protocols.

 

[nrcoyle]

I have been playing with receiving and decoding the micronet signal from my tacktick wind transducer as I am too tight to buy a T122, and I like hobby electronics. It is possible but I am still trying to iron out the protocol for decoding and that is only for wind. No idea what the signals from the other instruments will look like.

 

[[163233]]

I have been playing with receiving and decoding the micronet signal from my tacktick wind transducer as I am too tight to buy a T122, and I like hobby electronics. It is possible but I am still trying to iron out the protocol for decoding and that is only for wind. No idea what the signals from the other instruments will look like.

I'd be interested to see how you're going about it, because I'm also too tight to buy a T122 as well, it costs more than NASA's entire wind instrument and display.

 

[Gixer]

LOL, me too. Hence starting the thread

 

[nrcoyle]

I had been capturing the transmissions using a RTL-SDR Stick that I had lying around to try and work out the parameters and encoding.
I have now managed to get some consistent output which makes sense for angles, still not sure about wind speed.

I need to get to the boat to test some more and hopefully build a simpler circuit with a RFM69 board I have, but then I should be able to put up the code and details probably on github.

 

[Gixer]

Quick update from myeslf, I've managed to get a T122!

Next question is which Quark device to get for AIS receiving, GPS, Wi-Fi and output for DSC VHF..... I'm guessing the A026. More research needed!

 

[[163233]]

I had been capturing the transmissions using a RTL-SDR Stick that I had lying around to try and work out the parameters and encoding.
I have now managed to get some consistent output which makes sense for angles, still not sure about wind speed.

I need to get to the boat to test some more and hopefully build a simpler circuit with a RFM69 board I have, but then I should be able to put up the code and details probably on github.

Is it actually a digital signal?
I guess there can't be any encryption either?

 

[bniester]

I had been capturing the transmissions using a RTL-SDR Stick that I had lying around to try and work out the parameters and encoding.
I have now managed to get some consistent output which makes sense for angles, still not sure about wind speed.

I need to get to the boat to test some more and hopefully build a simpler circuit with a RFM69 board I have, but then I should be able to put up the code and details probably on github.

Did you ever make any progress with this? I am looking into this with RTL-SDR too but I have yet to figure out modulation technique being used by micronet. I tried with URH and GRC to demodulate and decode but no luck. If you could point me in the right direction, I have a PhD in signal processing that is willing to help me with this.. perhaps a collaboration??

Bill

 

[nrcoyle]

Still working on it, some details below of settings I have used successfully to point you in the right direction.

Modulation 2-FSK
Frequency 869.845MHz
Deviation 32 kHz
Bandwidth 250kHz
DataRate 76800 bps
SyncWord 0xb320 (Not sure if this is unique to my device or standard for all)

For the wind transducer you seem to get three sets of transmissions once a second,
A request from the display
Data from the masthead
ack from the display

I have focussed the decoding on the middle sentence, an example of which from my unit is:

413945c0415945c040212263030080a0a00001c080c0a006483ad72d6df4bacf4ccf5

for the wind sentences you get around 30 bytes of data,
I use the first 7 bytes to confirm the validity of the data. These bytes are always the same in the transducer transmission.
the wind speed data is between the 17, 18 and 19 bytes and is proceeded by hex 0a0a, decode by converting to decimal and dividing by 20.
The angle is in 2 compliments format and is proceeded by hex 0c0a for Left or positive angle or 0c0b for right or negative angle spread between the 23 and 25th bytes of the sentence.

Would love to hear any progress you make, and if you do manage to capture and decode any transmissions with URH, I would love to see them to try and understand the protocol further.

 

[bniester]

A

Still working on it, some details below of settings I have used successfully to point you in the right direction.

Modulation 2-FSK
Frequency 869.845MHz
Deviation 32 kHz
Bandwidth 250kHz
DataRate 76800 bps
SyncWord 0xb320 (Not sure if this is unique to my device or standard for all)

For the wind transducer you seem to get three sets of transmissions once a second,
A request from the display
Data from the masthead
ack from the display

I have focussed the decoding on the middle sentence, an example of which from my unit is:

413945c0415945c040212263030080a0a00001c080c0a006483ad72d6df4bacf4ccf5

for the wind sentences you get around 30 bytes of data,
I use the first 7 bytes to confirm the validity of the data. These bytes are always the same in the transducer transmission.
the wind speed data is between the 17, 18 and 19 bytes and is proceeded by hex 0a0a, decode by converting to decimal and dividing by 20.
The angle is in 2 compliments format and is proceeded by hex 0c0a for Left or positive angle or 0c0b for right or negative angle spread between the 23 and 25th bytes of the sentence.

Would love to hear any progress you make, and if you do manage to capture and decode any transmissions with URH, I would love to see them to try and understand the protocol further.

Awesome progress.. I'll let you know how I come along. I believe I made some good progress over the past couple days but I also think I recorded my signal with too much gain and got some signal cropping which is screwing things up. Going to try a re-record of the signal hopefully next week.

 

[[163233]]

I might have made some progress with this. Tackticks micronet appears to use a CC1000 IC which is a single chip RF transceiver that interfaces directly to a microcontroller via a serial bus.

Data sheet here: https://www.ti.com/lit/pdf/swrs048