1. NTP Server; used for 15 minute time interval, date-time stamping, and dayofweek (every 6th day, "LOG.TXT" file gets renamed to keep file size manageable. Every Saturday "LOG.TXT" gets renamed in the format "logxxyy" xx being the month and yy being the date; a new log.txt is created after every file renaming.
2. Dynamic web page of current observations for Last update time and date, humidity, dew point, temperature, heat index, barometric pressure (both inches of Mercury and millibars.)
3. Server files are listed as web links; clicking link prompts for "Open with/Save as." "FAVICON.ICO", and "ACCESS.TXT" are listed; however, they are for internal use and cannot "Opened with/Save as," result of clicking link produces "404 Page not found."
4. LOG.TXT file is appended every 15 minutes with the latest update; storing data from Dynamic web page.
5. ACCESS.TXT restricted file that logs client IP address.
6. DIFFER.TXT stores the difference in Barometric Pressure for the last fifteen minutes. Only a difference of equal to or greater than .020 inches of Mercury are logged with difference, date and time.
7. URL file names other than ones defined in the Sketch produce "404 Page not found." Methods other than "GET," produce "405" message and exits current request.
8. Audible alert from Piezo electric buzzer when there is Barometric Pressure difference of .020 inches of Mercury. I am interested in sudden drop of Barometric Pressure in a 15 minute interval. Serve weather more likely with a sudden drop. Difference of .020 inches of Mercury point is set for my observations to log and sound audible alert; not based on any known value to be associated with serve weather.
9. Two-line LCD Display of Barometric Pressure, in both inches of Mercury and millibars.
10. Tempature, Humidity, Barometric Pressure, and Dew Point have four embedded "ThinkSpeak.com" graphs on one web page. Graphs are created from Iframes provided by "ThingSpeak.com"
11. Added some logic for no NTP packet received; where the NTP packet gets requested until a packet is received. Created file "SERVER.TXT" for "SERVER" restarts --date and time.
12. Added Stephan Borsay's PHP code for received data requests from programs POST method. PHP code is used on a hosted Domain website.------------------------------------------------------------------------------------
Note this is a project in development; maybe offline or log files may be affected. Server is online 24/7; except during periods of testing.
Server is a "RobotDyn WiFi D1 R2" with 32 MB Flash Memory. Development Board, purchased from "RobotDyn.com" and Adafruit BME280 breakout board, purchased from "Adafruit.com" ; both are required for project, BME280 sensor is located indoors.
Developement board is Arduino friendly; can be programed using the Arduino IDE. Project cost is less than $20.00 for Development Board and one, Adafruit BME280 sensor for Barometric Pressure, Humidity, and Temperature.