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Windvane weather sensors with display virtual serial port connectivity
(2020-02-01, 06:51 PM)Twdee Wrote:
(2020-01-28, 10:31 PM)ddelorme Wrote: You need code to connect the 2. the davis pinout is on Sean's site i think.
there are 4 pins. 1 analogue wind direction 1 digital the wind speed  a ground pin and a power pin.  I sent 5 volts to power mine but i think Sean's is 12V.  i built a Esp32 version that sends data via wifi and controls the masthead light. It uses NMEA for the wind sensor  and sk for the anchor light. So i just need to send 12V up the mast. I did not include the BME XXX as i did not see much sense in putting the sensor in a sealed box. if your curious I would read though Sean's site. The davis does have a dead spot so I aligned mine  so the dead spot is to the front of the boat. this way dead spot does not really interfere with the boats navigation. I previously had used a cheap Chinese wind sensor but it broke in one season and was much heaver.  SK converts the NMEA to display in SK. Writing code for a boat is a bit more work then most iot applications as on the boat we are reading the device @10 hz where iot  stuff is in the 1 to 5 second range.

I started porting to NodeMCU(esp8266), which should be compatible with esp32 but immediately ran into library differences.
Think i resolved those; curious what libs were used - source/version?

Then ran into some compliler error(s).  Is the code on github Up-To-Date.

Ideally, i would like to convert to a Solid-State w/WIFI acquisition  method for getting wx/wind-info into OpenCPN/OpenPlotter/Pypilot.

Additionally, to retrofit a speed-through-water(paddle-wheel) sensor; acquiring via voltage or pulse.

Any feedback would be appreciated!

my code or Seans'  I used a esp32 feather due to the size and I had one. the ADC is 12bit and accepts a larger range of voltage. I would like to rewrite some  of the code. So the default web page could also display the values as well as set up the wifi connection to the Sk server. I had to add code to deal with the voltage ref fuse was not calibrated on my feather this should not be necessary on newer chips esp32 chips.
The paddle repair is a work in progress I had to get smaller less powerful magnets. I could spin it by hand but when i tried the water via tap the magnet would hold the paddle in position like the death stars tractor beam.
I am just getting my printer tuned in to print with PETG. May be the next print will work.

I just my weather sensor. I read through the post - still have a few questions if i understand the wiring correctly:
in github, the wiring:
rj12 - arduino - rj12 - connections
wire color - pin - pin
red - gnd - pin 3 - potentiometer power A - reed switch A
yellow - 5v - pin 5 - potentiometer power B
green - a7 - pin 4 - potentiometer reading
black - d2 - pin 2 - reed switch B

does it mean that the a7 and d2 are the two connections to the wind vane?
My other question: how does it communicate with the Rpi/ through wifi, or I need to connect it somehow?

Best regards,
to be clear: yes.

You can solder to d2, a7, gnd, and 5v the 4 wires of the wind sensor.
(2020-10-08, 11:57 PM)seandepagnier Wrote: to be clear: yes.

You can solder to d2, a7, gnd, and 5v the 4 wires of the wind sensor.

Hi Sean,

the weather sensor has only two cables, not four. So now wait to do? It is a rotavecta z195.

Best regards,
Yes, sorry as mentioned in email this sensor is not supported by my weather sensors which require 4 wire.
I have a similar issue in that opencpn is not receiving nmea sentences from Sean's weather module.  Have posted the same issue to

 I am trying to setup wind instruments for Opencpn on and Android tablet.

I have a Davis wind vane connected to Sean's weather sensor receiver and connected to a Huawei tablet via a USB OTG cable.

I can seethe nmea sentences being received by the tablet in a serial USB terminal app.

In opencpn connections there is a droop down to select for the serial port but in the nmea debug window no sentences are coming in other than GPS?

Does anyone have any ideas of what to try next? Have been through what feels like all different settings with no luck. Only thing I can think of is that thst the serial port address in the drop down is incorrect? Is that likely, I'm unsure how to check it?  Or perhaps opencpn needs some other permission to receive the signal from the USB port? When first connecting the USB cable a popup requesting permission for Opencpn to access comes up. 


Attached Files Image(s)
maybe only one app can access the serial port at a time?

This is really an OpenCPN issue. I would ask in the opencpn forum, since you clearly are getting the data into the tablet, it is a question of using a usb serial port ch340 on android which I have not tried myself... I should try it.
Hello Sean!
What is the optimal frequency of sending MVW for a tynipilot?
Now from my sensor there are 10 parcels per second. Tynipilot responds slowly to changes in wind direction ...
It outputs either 10 or 20 updates per second, but tinypilot filters the wind direction a lot. This is because at least with vane style sensors the momentum of the sensor it often swings, and also the boat rolling causes this too.

So I don't think it's the sensor output, and 10 is already fast, but the filtering maybe.

It will update faster in higher winds, so if you don't have wind speed or the wind is light it will update slower. Maybe the filtering needs to be adjustable?

How slowly? Is it too slow? What version are you running?

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