> My problem is that it seems that the code "reads" always 255, both for
> configuration (address 01h) and temperature (address 00h) registers.
>
> I have a TC74-A7 so its address is 1001-111
>
> This is what I get via RS232:
>
> Startup ok.
> Reading..
> Conf. 0255.
> Temp. 0255.
> Reading..
> Conf. 0255.
> Temp. 0255.
> and so on..

This is exactly what you get if the device wasn't properly addressed and
therefore not responding on the IIC bus.  Is the full IIC handshaking
occurring?  Do you get an ACK response to the address byte?


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