4 replies to this topic

[Eppetiano]

Hello all, please help me with this issue. I'm using the TMP102 I2C sensor with my netduino plus, i'm using the general I2CBus class but for a reason that don't now why my code is resulting in an exception. The error screenshot is the first file, listed above. The others are the class files i'm using. Please help me!! I don't now what i'm doing wrong!

Attached Files

•  errorMessage.png   120.91KB   29 downloads
•  I2CBus.cs   5.81KB   20 downloads
•  mySensor.cs   1.15KB   19 downloads
•  Program.cs   3.04KB   16 downloads

[Mario Vernari]

Eppetiano, I guess you shoudl specify the address in term of a 7-bit field, because the 8th is reserved for R/W. Try shifting right the current value (0x90) by one bit: 0x48. Also remember to connect two resistors (e.g. 10k Ohms) between the I2C lines (SCL, SDA) and the +3.3V. Cheers

[Eppetiano]

Thanks for you suggestion, Mario! Now i'm reading values on byte 1 and byte 2 from temperature register. Byte 2 = 140 Byte 1 = 19 How can i convert it to a single celsius value, please? Thanks in advance!

[Mario Vernari]

I'd try the following:

byte t1 = ...
byte t2 = ...
float temp = (short)(t1 << 8 + t2) / 16.0f;

Cheers

[mekros]

Did you get it working? I have my TMP102 working, you can grab that and see what the difference is.