Japie wrote: > Hello, > > First off all I like to apolegise if I'am posting in the wrong place, > please correct me if so. > > I'am looking for a data-logger on our tractor-puller > http://www.minimumrisk.nl based on OSS standards. > There are several data-loggers avaiable but there are all closed and very > expensive. > Someone in the rrd mailinglist pointed me towards owfs and 1wire sensors > and this looks very promesing but... > Are there sensors up to 1200 degrees celcius? > Can owfs/1wire read in mili-seconds? > Are there pressure sensors up to 10bar? > A few comments:
It sounds like you can handle some electronics work. As others have said, the DS2423 has 2 externally triggered counters. Reading these a few times a second is much better than trying to catch 90 switch closures a second (200+ samples/s to catch the on and off.) For hanging thermocouples off a 1-wire, check out app note 991. Pretty much lays out a way to use one of the 2760 battery controller to do the job. A measurement is made about 11 times a second, and when you read it you get the last value (this means that there is no conversion latency.) To compensate for the cold junction, you need to read the temperature off the chip every so often and do the software compensation. The temperature read will have a ~.5 latency as it converts the temperature. You can use the same chip to interface the pressure sensors The only ones I have ever used are the Motorola automotive series available from Digikey, but I'm not sure they have a 10 bar range. The great news about 1-wire is that the parts are dirt cheap. The bad news about 1-wire is that the bus and bus interfaces aren't the most noise resistant. You will want to be very careful in your shielding if this is an Otto engine rather than a Diesel. best of luck, jerry ------------------------------------------------------------------------- Take Surveys. Earn Cash. Influence the Future of IT Join SourceForge.net's Techsay panel and you'll get the chance to share your opinions on IT & business topics through brief surveys - and earn cash http://www.techsay.com/default.php?page=join.php&p=sourceforge&CID=DEVDEV _______________________________________________ Owfs-developers mailing list Owfs-developers@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/owfs-developers
