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kriswiner / MPU9250

Arduino sketches for MPU9250 9DoF with AHRS sensor fusion
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MPU 9250 in I2C does not return any data #61

Open abstruse123 opened 8 years ago

abstruse123 commented 8 years ago

Dear Mr. Kriswiner

Thanks for your project on MPU 9250, I could draw some support form it.

I interfaced MPU 9250 on the GY 9250 board to a PIC MCU through I2C protocol.

I wanted to read the WHO_AM_I register of MPU 9250. MPU 9250 does not return any data in response.

kriswiner commented 8 years ago

Do you have pullup resistors on the MPU9250 I2C lines? What is the voltage reading from SDA/SCL pins? Are you using the correct pins on the PIC for I2C?

abstruse123 commented 8 years ago

Thanks for ur response. Yes pull up resistors of 10 kohm each are present on SCL and SDA pins. Getting around 2V on both the pins.

kriswiner commented 8 years ago

That sounds about right. There must be some other problem. Try a different breakout or a different MCU to rule out the software.

-----Original Message----- From: abstruse123 [mailto:notifications@github.com] Sent: May 4, 2016 10:04 PM To: kriswiner/MPU-9250 Cc: Kris Winer; Comment Subject: Re: [kriswiner/MPU-9250] MPU 9250 in I2C does not return any data (#61)

Thanks for ur response. Yes pull up resistors of 10 kohm each are present on SCL and SDA pins. Getting around 2V on both the pins.

You are receiving this because you commented. Reply to this email directly or view it on GitHub https://github.com/kriswiner/MPU-9250/issues/61#issuecomment-217077184 https://github.com/notifications/beacon/AGY1qtt9QZ7OYg6cYDwMacZ2lj1nEepCks5 p-XpHgaJpZM4IWGGT.gif

abstruse123 commented 8 years ago

I am using 3.3V supply from a PIC kit to power the MPU 9250 board. Changed the resistors to 5 kohm each on SCL and SDA lines and now the WHO-AM-I register content is correctly read as 'q' i.e. ASCII value of 0x71.

kriswiner commented 8 years ago

There are 4.7 kOhm resistors already on the mini board; did you close the solder jumper on the front to enable them? Or maybe if not this is why you were having trouble?

-----Original Message----- From: abstruse123 [mailto:notifications@github.com] Sent: May 4, 2016 10:48 PM To: kriswiner/MPU-9250 Cc: Kris Winer; Comment Subject: Re: [kriswiner/MPU-9250] MPU 9250 in I2C does not return any data (#61)

I am using 3.3V supply from a PIC kit to power the MPU 9250 board. Changed the resistors to 5 kohm each on SCL and SDA lines and now the WHO-AM-I register content is correctly read as 'q' i.e. ASCII value of 0x71.

You are receiving this because you commented. Reply to this email directly or view it on GitHub https://github.com/kriswiner/MPU-9250/issues/61#issuecomment-217080929 https://github.com/notifications/beacon/AGY1qjX0qvsblqTYzi1ZfMZCgIHzVtFPks5 p-YSagaJpZM4IWGGT.gif

abstruse123 commented 8 years ago

I am using this board http://www.hotmcu.com/9dof-imu-module-with-mpu9250-p-172.html It has 10 kohm resistors and there are no jumpers provided on the board. It works most of the time with this 5 kohm tweak but not very consistently.

kriswiner commented 8 years ago

You get what you pay for it seems.