Concluding our totally solid-state alternative to seaweed and proverbs!

Last month the electronic circuits were discussed, the construction of the circuit board was described and some preliminary tests were outlined. We now conclude the tests, describe the enclosure and then the final alignment of the software.

The PIC Met Office monitors a range of sensors and processes data for the following conditions:

• Barometric pressure, in millibars
• Temperature, in °C and °F, including sub-zero
• Atmospheric relative humidity, as an RH percentage
• Soil moisture, bone-dry to saturated, as a percentage
• Light intensity, as a relative percentage, full sun to total darkness
• Rain fall, immediate (is it raining now?)
• Rain fall, cumulative (by how much has the water barrel filled and over what period?)
• Wind speed, in kph, mph and Beaufort, immediate and averaged
• Wind direction, immediate and averaged, 0° to 360°
• Wind chill factor
• Rainbow alert!
• Recording of all data to non-volatile serial memory (up to 256 kilobytes)
• Selectable data sampling rates, from 1 second to 1 hour intervals
• Serial output (9600 baud) of realtime and recorded data to PC-compatible computer, running under Windows 95/98/ME
• Bargraph and waveform displays on PC
• Data formatted by PC for reading as text file compatible with Excel spreadsheet/ graphing software and text editors
• Immediate display of monitored sensor values via alphanumeric liquid crystal display