BMP085 Reading Incorrectly
Moderators: adafruit_support_bill, adafruit

Forum rules
Talk about Adafruit Raspberry Pi® accessories! Please do not ask for Linux support, this is for Adafruit products only! For Raspberry Pi help please visit: http://www.raspberrypi.org/phpBB3/

BMP085 Reading Incorrectly

by Cody.Jiron on Thu Feb 14, 2013 1:25 am

I setup this sensor following the tutorial from the learning center but every time I run the example code I get a bunch of errors. When I eventually get a reading all of it is wrong. Temperature won't move off 12.8C no matter what and it reads that I'm 10,000 feet below sea level. No matter what I do it does the same thing every time. I'm very new to this but I feel like my sensor is bad. I just wanted to make sure I am not doing something dumb before I try to send back the sensor. My connections are firm and I'm using the adafruit breakout board and a mini breadboard. I'll post pics later. Thanks for any help
-Cody

Image

Image

Image
Cody.Jiron
 
Posts: 5
Joined: Thu Feb 14, 2013 1:16 am

Re: BMP085 Reading Incorrectly

by adafruit_support_bill on Thu Feb 14, 2013 7:16 am

What version Pi are you using?
What do you see in i2cdetect?
Make sure you have it configured for the right i2c bus for your version of the Pi: http://learn.adafruit.com/using-the-bmp ... pi-for-i2c
User avatar
adafruit_support_bill
 
Posts: 31814
Joined: Sat Feb 07, 2009 10:11 am

Re: BMP085 Reading Incorrectly

by Cody.Jiron on Thu Feb 14, 2013 10:08 pm

I'm pretty sure I have a version one. Here is what I see.

Image
Cody.Jiron
 
Posts: 5
Joined: Thu Feb 14, 2013 1:16 am

Re: BMP085 Reading Incorrectly

by adafruit_support_bill on Fri Feb 15, 2013 6:57 am

Looks like a version 1 and it is seeing the module at the right address. In Adafruit_I2C.py do you have the following line configured for bus 0?
Code: Select all | TOGGLE FULL SIZE
def __init__(self, address, bus=smbus.SMBus(0), debug=False):
User avatar
adafruit_support_bill
 
Posts: 31814
Joined: Sat Feb 07, 2009 10:11 am

Re: BMP085 Reading Incorrectly

by Cody.Jiron on Fri Feb 15, 2013 11:01 pm

adafruit_support wrote:Looks like a version 1 and it is seeing the module at the right address. In Adafruit_I2C.py do you have the following line configured for bus 0?
Code: Select all | TOGGLE FULL SIZE
def __init__(self, address, bus=smbus.SMBus(0), debug=False):


Yes it is set correctly.
Image
Cody.Jiron
 
Posts: 5
Joined: Thu Feb 14, 2013 1:16 am

Re: BMP085 Reading Incorrectly

by adafruit_support_bill on Sat Feb 16, 2013 7:59 am

One more thing to check: In the photo, some of the solder joints appear not to have flowed well onto the solder pad. The SCL pin is a critical one for i2C communication, but a couple others look suspicious as well.
Touch up those solder joints and try again. If it still doesn't work, contact support@adafruit.com with a link to this thread for a replacement.
User avatar
adafruit_support_bill
 
Posts: 31814
Joined: Sat Feb 07, 2009 10:11 am

Re: BMP085 Reading Incorrectly

by Cody.Jiron on Sun Feb 17, 2013 1:12 pm

Yep, bad solder joints, I have it updating to google docs. Thanks for everything

-Cody
Cody.Jiron
 
Posts: 5
Joined: Thu Feb 14, 2013 1:16 am