Hi
I made this one in last year, to monitor my aquarium temperature !
Since my tropical fishes really don't like water below +2C I had no reason to worry for the full scale range.
On the 1st pic you can see, basic config only give you +2C-- +150C
To get the full scale see the 2nd pic !
I designed my shc from the 3rd pic.
Did not have LM385 or other precision ref, only the Lm431 in my parts bin.
@+2C the output is +20mV, @ +102C +1020 mV,
there is 1000mV to use.
10bit =1024, 1000/1024=0.99609375 ~ so 1mV/bit if your refV is 1024mV
If your AD read 256, the C=256/10=25.6, if 258 then C=258/10=25.8
@1024 C=1024/10=102.4~
I hope this help :idea:
Don't ask for the CODE, I wrote it in BASIC, and the PIC molded in epoxy with the tepm sensor and collecting algae in my aquarium :lol:
Use this only as reference, I don't make documentation for myself !
There might be error's or flaw in my design !!
Works for me !! :wink:
STEVE