Even if they are powered you have to make sure you are waiting long enough before taking a reading after a temperature convert. At 12bits the DS18B20 takes as long as the DS18S20 (around 750mS).
On 2/29/2012 8:12 PM, Roberto Spadim wrote: > yes hehe my is the second, i connect 5v, 0v and owbus > does ds18b20 have a crc or another feature that shows the reset status > or something else? i could check for example.... > read 85 degree > read the crc value (or another reset value) > start of infinite loop: > read 85 degree again > read the crc value (or another reset value) > if crc value = reset value, loop, else good read > > i don't know if exists a reset counter or something like it in > ds18b20, does anyone know? > > > Em 29 de fevereiro de 2012 23:07, Eloy Paris<[email protected]> escreveu: >> Hi Roberto, >> >> >> On 02/29/2012 08:31 PM, Roberto Spadim wrote: >> >>> hi guys, i'm having a lot of problem with ds18b20 and 85 degree reads >>> what are every body doing when this occur? >>> today i read to times when this occur, and if it's 85 em both i allow 85 >>> degree >>> anyone know another good solution? >> >> If parasitic powered make sure that Vdd is connected to ground instead of >> leaving it floating. If they are being powered then I am afraid I don't have >> a good suggestion :-( >> >> Cheers, >> >> Eloy Paris.- >> >> >> > > ------------------------------------------------------------------------------ Virtualization & Cloud Management Using Capacity Planning Cloud computing makes use of virtualization - but cloud computing also focuses on allowing computing to be delivered as a service. http://www.accelacomm.com/jaw/sfnl/114/51521223/ _______________________________________________ Owfs-developers mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/owfs-developers
