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CocaColaKid
- 6th November 2006, 13:01
I don't believe this is possible but I thought I should ask just to be sure. When running the DS18B20 in parasite power mode is it possible to check the sensor to see if it is still busy doing the temp conversion? I know the dq needs to pulled to the rail during the conversion but I was wondering if it could be released, checked and re-applied before the chip lost power.

sayzer
- 6th November 2006, 13:21
Hi CocaColaKid,


Some parts from Data Sheet:

If the DS18S20 is powered by an external supply, the master can issue read time slots after the Convert T command and the DS18S20 will respond by transmitting 0 while the temperature conversion is in progress and 1 when the conversion is done. In parasite power mode this notification technique cannot be used since the bus is pulled high by the strong pullup during the conversion.



So you are right.
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