The Pressure Plug is a small board containing the BMP085 barometric pressure and temperature sensor. This tiny sensor communicates directly over I2C. Some processing is required to arrive at properly adjusted readings, this is available by using the “BMP085” class in the JeeLib library.
An I2C bus running at 3.3V is used as interconnect, with all the power and signal lines brought out to to both sides of the board to allow daisy-chaining with other I2C-conformant boards.
The pre-assembled version comes with the SMD-sized BMP085 chip and decoupling capacitor already soldered onto the board. Note that no 6-pin headers are included.
The PCB only variant contains just the board for the Pressure Plug. No parts, no headers.
As connectors you can use a Plug Headers set with 10 male and 10 female 6-pin headers, which makes it easy to connect multiple plugs and JeeNodes in a “standard” way. Or you can solder the board directly in place for more permanent use.
The documentation and full design details are freely available.