Hi, I want to connect gyro (MPU6050) and barometer (BMP180) to the Uno. They both use i2c protocol and now I know after reading this BMP180 and mpu6050 together i2c - Programming Questions - Arduino Forum that modules can work together. The only thing I should do is remove some pull-up resistors.
But I got may be a stupid question...
As far as I can tell the topic I linked above considers two modules running under the same voltage. let it be 3 V.
But what if I my gyro running under 5V and barometer under 3V? So, lets say I remove pull-up resisters from the gyro and the total amount of resistance will be defined only by barometer pull-up resistors.
Will something bad happen if I solder i2c lines of one module with another module lines? Because I think that this way I put different voltages in parallel way and the resulting voltage won't be 5 and not 3 for sure.
Please tell me if I'm mistaken and especially if I'm not
And what should I do for gyro (5V) and barometer (3V) working all together sharing the same i2c bus?
If you use a 5V sensor I'm betting you already use a 5V Arduino. So to use the 3V sensor you need a level shifter. Does not matter if you use it together with another sensor or alone. To go from a 5V Arduino to a 3V sensor you need a shifter. And for I2C you need at least for the SDA line a bidirectional level shifter.
Yes you do. The 3V3 out on a Uno is nothing more then a power output. It's just a 3V3 regulator from the 5V line of the Arduino. But it does nothing with the signal lines (outputs) from the Arduino. Those are still 5V. And that BMP180 can't hand;e that
And now I look at it, the MPU6050 is 3V3 as well. So or use a level shifter or use a 3V3 Arduino like the Arduino Pro Mini 8Mhz.
septillion:
But it does nothing with the signal lines (outputs) from the Arduino. Those are still 5V. And that BMP180 can't hand;e that
but there're a lot of manuals which describe how to connect bmp180 to the arduino board and a lot of boards in the manuals are UNO which you said the module can't handle
for example
s0bes:
and I have already connected MPU6050 to the UNO without any level shifters
I think you've mistaken about shifters so I wait for other replies
The maximum supply voltage for the mpu6050 is 3.46 V, and no logic input can be higher than this.
I don't imagine Invensense are mistaken about their own product.
s0bes:
Hi, I want to connect gyro (MPU6050) and barometer (BMP180) to the Uno. They both use i2c protocol and now I know after reading this BMP180 and mpu6050 together i2c - Programming Questions - Arduino Forum that modules can work together. The only thing I should do is remove some pull-up resistors.
But I got may be a stupid question...
As far as I can tell the topic I linked above considers two modules running under the same voltage. let it be 3 V.
But what if I my gyro running under 5V and barometer under 3V? So, lets say I remove pull-up resisters from the gyro and the total amount of resistance will be defined only by barometer pull-up resistors.
Will something bad happen if I solder i2c lines of one module with another module lines? Because I think that this way I put different voltages in parallel way and the resulting voltage won't be 5 and not 3 for sure.
Please tell me if I'm mistaken and especially if I'm not
And what should I do for gyro (5V) and barometer (3V) working all together sharing the same i2c bus?
Somebody posted a real technical explanation how I2C works - open collector etc. Sorry, do not recall the thread title. Just Google for it somehow and get away from all these voodoo advises.
