🔳A couple of our recent projects involving sensors & WiFi, ( 'Solarometer' 📅13.10.2024 & 'Greenhouse Gas Sensors' 📅01.12.2024 ), have an integrated webserver hosting a webpage so that the sensor readings can be displayed on a client device, e.g., phone 🖁or computer💻, running a browser. Either HTTP or AJAX protocol was employed for the server-client connection.
A🪴'Plant Water Monitor' is a new project which will use a Websockets Server & Protocol instead. Websockets was briefly mentioned in the 'Solarometer' post. To recap, unlike HTTP or AJAX, Websockets provides real-time server/client communication over a continuously open full-duplex bidirectional connection 🔁, requiring no page refreshes or other requests; just the measurement data ( not the entire page ), are sent automatically, with minimal latency.
Testing Websockets has been successful. The Websockets server, ( programmed on the µ-controller in the 🪴Plant Water Monitor ), is assigned IP address 192.168.1.51 when it establishes a connection with our Wifi network router access point. Navigating to that address with a browser on a 🖁phone or 💻computer displays the page to see the data being updated.
Several variations of a webpage were designed, ( again using HTML, CSS & JavaScript ). Which one will ultimately be chosen has still to be decided. Each has the filename soil-moisture-sensor-vn.html. Websockets protocol is used to automatically update ( ⏱every hour or every minute ) the moisture﹌ readings, time stamp of the last reading, and Wifi signal level, in real time.⌚
 |
| V1 viewed on a phone |
V1 is the basic page design having the essential features. Wifi signal level ( at the moisture sensors location ), moisture ﹌readings at two locations and time-stamp are updated automatically without any intervention required from the user.
 |
| V2 + WiFi signal level meter |
V2 as V1, with the addition of an analogue bar-meter showing the WiFi signal level changing to assist in choosing a location for the remote sensor.
 |
| V3 + popup notification |
V3 as V1, with the addition of an alarm ⏰ condition pop-up advising that action should be taken on the basis of the reported moisture measurement. 🥀🏜
 |
| V4 + button & background image |
V4 as V1, with the addition of a 'button' which when tapped will show or hide the moisture level descriptions, and with the addition of a background image of the 🪴'Plant Water Monitor' itself.
Note that the ⌂"home" icon in V2, V3 & V4 is continuously spinning.
