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tutorials:learn:sensors:bmp085.html [2011/07/18 14:18] daigo [Wiring] |
tutorials:learn:sensors:bmp085.html [2011/07/18 14:25] daigo [Wiring] |
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Unfortunately, the i2c lines on most microcontrollers are fixed so you're going to have to stick with those pins. | Unfortunately, the i2c lines on most microcontrollers are fixed so you're going to have to stick with those pins. | ||
- | You may be wondering, how is it OK to connect a 3.3V chip like the BMP085 to 5.0V data pins like the Arduino? Isn't that bad? Well, in this specific case its OK. I2c uses pullup lines to the 3.3V power pin, so the data is actually being sent at 3.3V. As long as **all** the sensors/device on the i2c bus are running on 3.3V power, we're fine. \\ \\ However, don't use a 5.0v powered i2c device (like the DS1307) at the same time as a 3.3V device like the BMP085! | + | <class warning> |
+ | You may be wondering, how is it OK to connect a 3.3V chip like the BMP085 to 5.0V data pins like the Arduino? Isn't that bad? Well, in this specific case its OK. I2c uses pullup lines to the 3.3V power pin, so the data is actually being sent at 3.3V. As long as **all** the sensors/device on the i2c bus are running on 3.3V power, we're fine. \\ \\ However, don't use a 5.0v powered i2c device (like the DS1307) at the same time as a 3.3V device like the BMP085! | ||
+ | </class> | ||