Gina

Do you use a Real Time Clock with that James?

Looking at the wind vane calculations... I will have 8 digital inputs to the ESP32 two of which may be on at the same time. A "sledgehammer" approach would be to assign values of 1, 2, 4, 8, 16 etc. and then use a look-up table to convert to 16 values 0-15. This table would have 256 entries. I'm wondering if this would put a strain on the ESP32. Guess I can try it and see. Then Consensus Averaging with magnum maths and put the result in the HTML string.

In parallel with thinking about sensor locations I'm looking into the coding. The trend in atmospheric pressure would be a useful extra and quite easy to do. Maybe max and min temperature but there would be a need to reset it. For the wind instruments, instantaneous wind speed has little meaning. I'll probably average over 5 minutes. Data for mean speed and gust would be useful. The wind direction is rather more complicated. Firstly the read switch on/off reading has to be converted to one of sixteen. Then this would be smoothed with Consensus Averaging. It would be nice to generate a Rose Chart but that will have to be for the future.

Seems the "easy" places to put the Stevenson screen would not be good! The north obsy wall, while shaded from the sun would not allow much airflow. On the wind sensor pole would suffer from heat from the black rubber roof of the obsy. Same with the ASC pole. Here's a rough aerial view courtesy Google (a few years old). The rough ground cover and the whole of the area is currently overgrown with thistles but will be cleared. I'm thinking perhaps on a fence post on the boundary where I took a tree down might be as good as anywhere (if within WiFi range). The greener area is my property - the not so green area is my neighbours field.

The prevailing wind is SW. The observatory is about 15° off east-west, in a clockwise direction viewed from above. The wind sensors are on the SW corner in this photo. The long wall with the ASC pole attached is where I was thinking of putting the Stevenson screen. Met Office suggest a height of 4ft (1.2m) but pics of lots of weather stations show it at all sorts of heights. Maybe it doesn't make much difference

Have you any comments about the location of the Stevenson screen Wim?

Found the problem - bad connection. WiFi working again but now have a bad connection to the BME280. Just using jumper wires and they aren't very tight. I'll build it on a stripboard shortly. Later... Working again now.

Well it was but now I've lost connection. Hope this doesn't mean the WiFi is unreliable. I'll pop out shortly and see if I can see any reason.

Have the ESP32 with BME280 in the scope room near the pier. Working fine.

Can I have opinions please. Is the north wall of the observatory the best place for a Stevenson screen for the outside measurements of temperature, humidity and pressure? Would I get sufficient airflow it? Or would it be better on a post away from the building?

I've designed the Stevenson screen. It'll take a while to print! It is in one piece except I may put a bottom on it. That was on at first until I realised I couldn't get the electronics into it! 🤣

Having looked into where I would like to put the temperature and humidity sensors in the scope room and outside I'm thinking it may be worth using separate ESP32s. After all they don't cost much and I don't know how far from the ESP32 I can have the DHT22. The scope room sensor could then be on the pier giving more accurate data on imaging conditions.

What do you find better about the Thonny micropython editor?

I may install the ESP32 with BME280 and DHT22 in/on the observatory tomorrow. I'll design and 3D print a tiny Stevenson screen for the outside sensors and mount the scope room sensor just inside on the other side of the north wall. I think I'll put the BME28- outside in the Stevenson screen as the air pressure may be affected in the obsy by wind blowing through it.

I might go on to add code to store data and make tables generated from logged data. I think graphs might be pushing it. I shall need to look into how much data I could store within the ESP32. I too think it would be better to schedule data acquisition and store it, then let the web access code read the stored data rather than actually take it. That is the way I have always done things. You have to do this for wind and rain measurements anyway.

Ordered another ESP32 module. So much easier to deal with the exact same device for the different weather station sensors. I shall probably be ordering more as I can see other uses for them.

This implementation (either simple or pretty) reads the weather data when the web page is accessed. With the wind sensors, the anemometer produces interrupts to count revolutions for wind speed, the count being taken and zeroed each second (or could be more). The wind speed would be updated at each second (or whatever the interval) and this would be read by the web access part of the code. Similarly the wind direction would be read at intervals and I propose to add code to effectively "smooth" this fast changing data and have the web access code read this. I propose to use Consensus Averaging for this. I expect the internal clock to be accurate enough to provide the interval timing - I don't think it needs an RTC at this stage. That would only come when I add data logging at a later stage and that would be separate.

Is this just with the "pretty" version of the web site which uses Google icons? I don't need pretty pictures.

I'm wondering if a single ESP32 would be able to handle all the data processing needed for the wind data as well as the web server. The anemometer will want to use interrupts to count the revolutions (4 counts per revolution to give enough wind speed resolution).

I now have a framework I can work in to add other weather measurements. The ESP for the scope room and outside could be an ESP8266 but it may be easier to use an ESP32 as I already have the code for it and know it works. I don't know if the ESP8266 can handle a web server. I shall certainly be using an ESP32 for the wind sensors as I need the number of GPIO pins. I also will have a fair amount of code to add to process the wind data before making a web page

But are we comparing outdoors with indoors here? My ESP32 and BME280 are sitting on my living room table (aka work bench).

The "pretty" version of the web page.

I thought these ESP32s were supposed to be low power! This one is drawing 0.08A on 4.9v according to my bench PSU. Probably needs coding to put it into a low power mode if you want to save power. No problem here as I shall be running it off my main obsy supply via a buck converter. Goes to 0.09A when accessed from browser.

Yippee!!! It works!! Altitude is wrong though - it's 200m ASL here! According to Google!

A stage further... Uploaded Wim's WebServer sketch having set SSID and PW and also connected BME280. Testing from serial and pressing EN button I get a good result. Next to connect ESP32 to 5v Vin and see if it all works.