At 04:41 PM 2/8/98 -0500, you wrote: > Can someone direct me to a PIC (or other sbc) project for a complete weather > station? I have been looking but have not had much luck. > If not, can someone direct me to reflectors for other single board computers? > Thank you. > > Jim Pruitt Jim, I've designed a 16C74-based weather station. I've added some DIY (Do It Yourself) and commercial references at the end of this message. First, I only know of one complete DIY weather station project and that was back in 93 and is out of date given what you can do now days. I strongly recommend you buy a good commercial wind sensor and rain gauge. Though I designed my own outdoor temperature and humidity sensors, I would also recommend a commercial integrated sensor but they are expensive ($100+). The main problem I've had was shielding the humidity sensor from ambient light. These sensors not only provide temperature and humidity but they are also required to calculate Wind Chill, Dew Point, and Heat Index. My system works very well but a combined commercial sensor is easier to mount and eliminates the packaging `hassle'... I started designing my system over 2 years ago and the work is still in progress... The hardware has been running for over a year and tracks the local (Portland, OR PDX) National Weather Service very closely. I've had the PC interface up for around 5 months. The wind sensor is the weak point... When I went into this, Davis Instruments was reluctant to sell me their wind sensor. I understand that this has changed. Also, I was unaware of Peet Brothers at the time. I used a refurbished, 1st generation, Heath sensor. I would like to update this part to a Davis Instruments or Peet Brothers sensor. My concern was to find an OEM source. Davis rented time in one of NASA's wind tunnel to test their sensor... While I'm still considering a commercial product I'm leaning towards breaking the design into parts and doing magazine articles as well as public PIC projects. Doing a complete weather station is too complex for a typical article or simple project. Also, my system includes energy management functions. If you do decide to `roll your own' I would be glad to help with hardware issues. I would'nt be of much help with code as it's part of a complex state machine... The current capabilities of my station are: Temperature (0.1F Resolution). Outdoor Attic Upstairs Downstairs (Mounted in the furnace thermostat) Basement Kitchen (Sensor not connected yet) Humidity (1% Resolution, 1 - 100%). Outdoor Indoor Barometric Pressure (0.01 InHg Resolution). Rain Gauge (Davis Intruments' Gauge. 0.01"). Wind (Old Heath... 3 mph sensitivity, 16-point direction resolution). LCD Display. 4 x 20 Displays all of the above, Wind Chill, Dew Point, Peak Wind Gust, and Time. Other display modes for Day-Date, Heat Index, High/Low Temperature summary, and A/D Calibration. Keypad. 16 Key Calibrate A/D Calibrate Barometer Clear Rain Count. Maunual Software override. Clear Peak Wind Gust. Maunual Software override. Reset High/Low Temperatures. Maunual Software override. Clear SRAM Data Storage Set Clock Nonvolatile 512K SRAM/RTCC stores data for up to a year. Remote Wind Display (PIC16C84), SPI-style, Optoisolated. Parallel bus interface. Auxilliary SPI-style Interface. PC RS232 Interface. Windows 95, 9600 Baud Displays current data, downloads historical data, graphs historical data with a variety of statistical functions, and more... Alarms. All sensors. Still need to work on the Keypad/LCD/PC interface Energy Management Heating zones. Lighting control. Load-shedding, more. Security This is in work. Like the above, it's low-level structure is in place. There is more to this. Most data conforms with NOAA's Federal Meteorlogical Handbook and the World Meteorlogical Organization. I would like to add METAR reporting format. I have'nt discussed energy management as that is still in work and unique to a given structure. There are more features I'd like to add to the base unit and more LCD display options. I'm in the process of moving the code to the 16C77. This will allow me to finish the Alarms, Security, and Energy Management interface. I'm also adding things to the PC side including sunrise/sunset. While that's trivial there is a lot more to add given the raw data from the base unit. Currently, the PC side does not support Alarms, Security, or Energy Management. However, the PC is reduced to a configuration/schedule data base for these applications. The PIC needs to handle these functions in real-time. Since I want the base unit to operate autonomously, I also need to improve on the Keypad/LCD interface for these functions. The following are some commercial sources (There are many others but they are very expensive and/or they have a very small home-market share): (1) Davis Instruments. They are well established and have systems all over the world. If you go commercial, I'd recommend them first. Expect to pay around $500 for a full weather station. http://www.davisnet.com (2) Peet Brothers. I don't have any experience with them but they have a lot of interesting products and seem to be cheaper than Davis. They are very open about their data and sensor formats. http://www.peetbros.com/index.html#TOP (3) Radio Shack. This system is made by Oregon Scientific. Their web site does'nt give much info. This seems to be the best deal for a packaged system but someone else here mentioned that their data format is proprietary. Though I'm in Oregon, I have never talked with them as I was unaware of their products when I designed my system. Do a web search or try: http://www.oregonscientific.com (I think that was the link) The following are some DIY references: (1) PIC 16F84-based Wind sensor. Innovative design using 3 cups, one with a tab. It detects direction by variations in the pulse frequency. You need to buy a package of templates and a PIC for $27. Complex mechanical construction. You have to fabricate several parts. Direction resolution is 1.4 degrees. Direction measurement accuracy depends on how accurately the sensor is made. With careful construction, +/- 5 degrees can be expected. Speed resolution is .5 knots. You calibrate the wind speed yourself in your car... RealTime Control http://www.alphalink.com.au/~derekw/ane/anemain.htm (2) Electronics Now, Oct/Nov 93. Complete weather station project. Fairly easy mechanical construction. Original company and parts no longer exist but most parts are available from the hardware store. Apparently another company sells kits and an assembled version but even the kit price was `ridiculous' compared to commercial systems and the original article... Electronics Now, Aug 95. Another wind sensor based on the revised Heath wind sensor which is hard to find. Based on a 8031. www.gernsback.com (Electronics Now and Popular Electronics) (3) Circuit Cellar Ink, #32 Mar 93. A video wind sensor. I don't have the issue in my archives. Circuit Cellar Ink, #68 Mar 96. PIC-based wind sensor. Uses Davis Instruments wind sensor. Includes calibration data (from driving a car)... www.circuitcellar.com - Tom