Guru
Joined: 11/02/2018
Location: AustraliaPosts: 3321
| Posted: 10:56pm 31 May 2026 |
More experimenting with the nongenuine DS18B20.
It's conversion time is much faster than for the genuine unit.
It does high res 1/16° conversions in less than 34mS.
With the temperature changing rapidly it really does get new values that fast.
It's accuracy, however appears to be a little less, almost 1° high compared to a genuine unit and a pair of AHT10s.
Edit.
> 'Non-genuine DS18B20
> t2=timer:OneWire WRITE 9,1,2,204,68:t=timer:do:OneWire READ 9,4,1,d:loop until d :? timer-t,timer-t2
33.237 35.562
> ' So about 2.3mS to start conversion and 33.3mS to carry it out.
>'genuine DS18B20
> t2=timer:OneWire WRITE 10,1,2,204,68:t=timer:do:OneWire READ 10,4,1,d:loop until d:?timer-t,timer-t2
479.366 481.694
>
> t2=timer:OneWire WRITE 9,1,2,204,68:t=timer:do:OneWire READ 9,4,1,d:loop until d :? timer-t,timer-t2
33.237 35.562
> ' So about 2.3mS to start conversion and 33.3mS to carry it out.
>'genuine DS18B20
> t2=timer:OneWire WRITE 10,1,2,204,68:t=timer:do:OneWire READ 10,4,1,d:loop until d:?timer-t,timer-t2
479.366 481.694
>
Edited 2026-06-01 11:09 by phil99