Peculiar I2C issues on Teensy 2.0, not on Teensy 3.0

[EasternStarGeek]

Folks,

I posted on this topic before, regarding a Temperature/Humidity sensor I purchased from Adafruit- the AM2315. I have since learned some interesting new things. For one, the problem that I am having appears only on the Teensy 2.0, but not on my Teensy 3.0.

Please see this link:
http://forums.adafruit.com/viewtopic...AM2315#p204516 (recent)

and this link:
http://forums.adafruit.com/viewtopic...AM2315#p200097 (the original)

for some historical information.

The thing that is killing me here is that the problem appears with the Teensy 2.0 (standard 5V config), but not the 3.0. I am using v1.03 of the Teensyduino IDE.

The fact that the bad data follows changes in humidity makes me think it might be a timing issue. What are the differences between Teensy 2.0 and 3.0 that could account for such a difference?

(btw, Thanks Paul, for your recent reply to my AFI post. I will look at the library and take your suggestion)

[PaulStoffregen]

Definitely edit the library to print the raw data. Maybe that will make the problem obvious?

What are the differences between Teensy 2.0 and 3.0 that could account for such a difference?

Both do pretty standard I2C. The Teensy 2.0 is virtually identical to the AVR used on Arduino Uno, which is the board Adafruit uses to test all their libraries. It really should work.

Without more info, I really have no idea why it's doing this. At least you have an easy path to getting more info...

[EasternStarGeek]

Bump...Problem solved.

The sensor does not like being queried too frequently.
For details, see link:
http://forums.adafruit.com/viewtopic...AM2315#p204516 (recent)

Thanks, Paul!