Using the BMP085 Pressure Sensor

ravinrabbid edited this page Mar 28, 2012 · 1 revision
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Hardware

Because the ATmega's TWI pins are already used by the two status LEDs, you need to remove the resistors R22 and R24. Now solder the BMP085's SDA pin to pin 20 (R24) on the ATmega and the SCL pin to pin 19 (R22). Finally connect the BMP085 to VCC and Ground and you are done.

If you are using anything other than the Sparkfun BMP085 Breakout Board you may also need two 4,7k pull-up resistors for SDA and SCL.

Software

In hexabus_config.h set I2C_ENABLE and PRESSURE_ENABLE to 1.

If you also want to use the BMP085's temperature sensor, set TEMPERATURE_ENABLE to 1 and TEMPERATURE_SENSOR to 2.

Pressure can now be read via EID 6 and temperature via EID 3.