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Author Topic: Troubles with BMP085 pressure sensor & I2C protocol  (Read 3310 times)
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Italy
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Can't tell you if you've damaged anything yet but if you did it would typically be the lower voltage devices.

I think so, but now even DS1307 RTC refuse to work... its behaviour is the same of the BMP085, while its supply voltage is 5 V
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Worcester, MA
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What size pullups are you using for the RTC?
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Italy
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10k for both SCL & SDA (obviously one each)
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Italy
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Last night, in spite of sleeping, I was thinking about 3.3 level conversion of signal. Should something like the attachment works (apart the mistake that the central resistor should be 220R in spite of 330R)? I even thought that it should work fine for digital output, but dunno know if it's the same for I2C... even thought that a diode should be mounted in parallel to resistor to avoid an extra lowering of 3.3v signal sended from sensor to I2C pins A4 & A5.

I bought a logical level converter, but if the method I thought about works it would be easier for me to integrate it into my own shields...

I'm sorry I tried to read something about I2C protocol but I understand almost nothing when applying it to Arduino.


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« Last Edit: July 04, 2011, 05:46:48 am by lucareds7 » Logged

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