ESP8266 Community Forum

I did not have a look at the library but some ATmega Arduino libs utilize integer arithmetik and do not 1:1 work on esp8266 without checking correct variable bitwidth.

It is not an intrinsic problem with the libraries running these sensors. I have lots of temperature sensors using these and they give accurate results.

Finally sorted

@Ian
After a massive waste of time I tried your suggestion and it worked !!. I cannot understand why it should work OK on a pro mini @3.3v but not on an ESP8266 , as apart from the cpu speed all things should be equal. I have sourced these chips from two different suppliers and they all behave identically.

I have now attached a 3.3k resister to +5v (ESP inputs are 5V rated - so I've read) whilst using it on a 3.3v esp and that seems to work very well also.

Thanks to all who took the time to comment.

Best Regards

dataguy