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The WX #175 Kit was recently developed to provide a high quality weather system at an affordable cost. It is a kit of parts, suitable for assembly on a solderless breadboard or similar. It was designed to interface with a PC COM Port or similar at 9600 baud. (A USB to RS232 converter may be used). * An interface with an MPX4115AP or MPX4115AS pressure sensor to measure barometric pressure. * Interfaces with up to two Sensirion SHT-71 relative humidity and temperature sensors. The idea is to provide the capability to measure RH and temperature locally and also at some point up to 100 feet from the unit. * Two twisted pair runs to interface with up to sixteen Dallas DS18B20 temperature sensors on up to 200 feet of twisted pair cable on each run. * Five 10-bit analog to digital converters. * A counter which may either be used to count events or used to count events over a specified period of time. As time permits, we are able to occasionaly build partially assembled units on an Olimex PIC-PB28 prototyping board which provides the following; * Wall power unit which provides nominally 9 VDC at 300 mA which interfaces with a coaxial type connector on the circuit board. * 5 VDC regulated supply using a 7805 and associated filter capacitors. * Six foot serial cable to interface with the DB9 connector on the board. * MAX232 and associated capacitors to provide signal levels that permit an interface with a PC COM port or similar. * Programmed Microchip PIC, 28-pin DIP in a socket. * One MPX4115AS pressure sensor. * One SHT-71 RH and temperature sensor. * Screw type binding posts, one 12-position and one 11-position. Note that all of this is wired. In addition, the wiring associated with the two twisted pair runs to the DS18B20s is provided at two of the screw terminals. One DS18B20 temperature sensors is provided. Thus, this package is a fully assembled unit which permits you to measure atmospheric pressure, relative humidity and temperature on the board and one temperatures at a remote point using a DS18B20. With minimal wiring, you can add five 10-bit A/Ds, the counter function, two TTL outputs, two TTL inputs and a second remotely located SHT-71 RH and temperature sensor (not provided with this package). You may wish to add the wiring for the five A/D converters, for a second SHT-71 RH and temperature sensor (not included in this package), the counter and the two TTL outputs and TTL inputs to meet your specific applications. This wiring involves simply conecting from a terminal on the processor to a screw type binding post. The package may be tested using HyperTerm or a similar terminal emulator. However, this package does not include software for the PC. This package is intended for hobbyists who desire to use their creativity in developing software using Visual Basic, Visual C++ or similar. * Western Europe - $6.00 (without wall power unit) * Australia, New Zealand - $6.00 (without wall power unit). (all content is the responsibility of the poster) |
c-wade@oklahomaselltoday.com (Carlos Wade) for more information. All emails will be forwarded to the poster's actual email address.