Weather station with pressure reading, relative humidity, indoor & remote outdoor temperature display.
Both Celsius or Fahrenheit & mbar/hPa or mm HgĀ supported. With calendar & clock. Easy 3-button user-menu. 42 hour-history display (curve). Auto-memory & display of all high and low-values.
PIC 18F452 running at 4 MHz, power saving sleep mode. Sensors are only turned on when needed.
All parts are available in our online shop.
Schematic & pcb (Eagle 4.11e), source code (CCS) and hex file available. Updated on May 6, 2006.
Future developments: fully solar powered.
Circuit explanation:
Now this was a huge project! All sensors had to be fully tested one at a time, wireless communication had to be perfect, various LCDs were tried. Nevertheless, hereās the result: hope you enjoy it!
The circuit may be powered by a small 9V battery, but youād better take a couple of AA-batteries. A 6-pack will last a several months. Consumption for the base station is around 8 to 9 mA whilst active and only 2 to 3 mA in sleep mode (LCD remains on.) The transmitter takes slightly less.
The receiver (base station) is active during 5 seconds & then goes to sleep for 45 seconds. The transmitter takes a nap every 30 seconds or so.
Menu mode is entered when pushing the āmenuā button (whatās in a name?) for 1 second. Browsing & value changes are done with the āminā & āplusā keys. When in normal mode (like in the picture above), the āminā and āplusā keys can browse through the different histories. All these controls will wake up the processor if it was in sleep mode.
On the left-hand side of the LCD we have (from top to bottom:) Outside temperature, Pressure, Inside Temperature, Relative Humidity, Calendar and Clock.
On the right: High value of the past 42-hours, Bar graph histogram (right is most recent value), Low value.
All sensors are read & LCD (left-hand side) are updated every 50 seconds. Histogram is updated on the hour (e.g. 10h00, 17h00, 22h00,ā¦)
All data is stored in EEPROM and is loaded at power-up. In case of a power failure (or when changing batteries), there will be no data (nor history) lost.
For more detail: Weather station using PIC18F452 Microcontroller
About The Author
Ibrar Ayyub
I am an experienced technical writer holding a Master's degree in computer science from BZU Multan, Pakistan University. With a background spanning various industries, particularly in home automation and engineering, I have honed my skills in crafting clear and concise content. Proficient in leveraging infographics and diagrams, I strive to simplify complex concepts for readers. My strength lies in thorough research and presenting information in a structured and logical format.
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