Thank you! The DS27xx are a nice set of chips, but come from the "Battery Group" and thus are out of the 1-wire mainstream.
Paul On 5/24/06, Jan Bertelsen <[EMAIL PROTECTED]> wrote:
I've checked the data sheet of DS2740, DS2751, DS2770 and DS2780 which are the devices in the code of ow_2760.c DS2751 is similar to DS2760, but is covered by my correction. DS2740, DS2770 and DS2780 doesn't have this little "feature" so - no the correction isn't needed to be made for the other devices. Jan B. On Tue, May 23, 2006 23:16, Paul Alfille wrote: > Now that's the way to file a bug report! Analysis and a patch. > > Applied. > > Question, does the same correction need to be made for the othe DS27xx > devices? > > Paul Alfille > > On 5/23/06, Jan Bertelsen <[EMAIL PROTECTED]> wrote: >> Hello, >> >> I've tested a DS2760 measuring a thermocouple type K and got some >> strange >> readings. The current was many times greater than the DS2760 is designed >> to and the temperature in directory 30.xxxxxxxxxxxx/typeK/temperature >> didn't match the temperature at the thermocouple. >> >> According to the data sheet for the DS2760 (page 8) the three least >> significant bits of the current register has no value (marked as x) - so >> I >> think the current reading is a factor 8 too high and that the factor f >> in >> function FS_r_vis() in ow_2760.c should be divided by 8 (f = 15.625E-6 >> / >> 8). >> >> Further I found that the special if-statement for the DS2740BU also >> changed the factor f for the DS2760 when reading from directory /typeK/ >> (but not when reading the main directory for the DS2760), so I moved it >> into the case for DS2740 (I don't know if this is the right place). >> >> With these small changes I got a reading matching the actual >> temperature. >> >> Included below is a diff of the changes. >> >> Jan B. >> >> >> [EMAIL PROTECTED] c]$ diff owfs-2.3p7/module/owlib/src/c/ow_2760.c >> owfs-2.3p7/module/owlib/src/c/ow_2760.c~ >> 555d554 >> < if ( pn->ft->data.v ) f = pn->ft->data.f ; // for DS2740BU >> 559c558 >> < f = 15.625E-6 / 8; >> --- >> > f = 15.625E-6 ; >> 567a567 >> > if ( pn->ft->data.v ) f = pn->ft->data.f ; // for DS2740BU >> [EMAIL PROTECTED] c]$ >> >> >> >> ------------------------------------------------------- >> All the advantages of Linux Managed Hosting--Without the Cost and Risk! >> Fully trained technicians. The highest number of Red Hat certifications >> in >> the hosting industry. Fanatical Support. Click to learn more >> http://sel.as-us.falkag.net/sel?cmdlnk&kid7521&bid$8729&dat1642 >> _______________________________________________ >> Owfs-developers mailing list >> Owfs-developers@lists.sourceforge.net >> https://lists.sourceforge.net/lists/listinfo/owfs-developers >> > > > ------------------------------------------------------- > All the advantages of Linux Managed Hosting--Without the Cost and Risk! > Fully trained technicians. The highest number of Red Hat certifications in > the hosting industry. Fanatical Support. Click to learn more > http://sel.as-us.falkag.net/sel?cmd=lnk&kid7521&bid$8729&dat1642 > _______________________________________________ > Owfs-developers mailing list > Owfs-developers@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/owfs-developers > > ------------------------------------------------------- All the advantages of Linux Managed Hosting--Without the Cost and Risk! Fully trained technicians. The highest number of Red Hat certifications in the hosting industry. Fanatical Support. Click to learn more http://sel.as-us.falkag.net/sel?cmdlnk&kid7521&bid$8729&dat1642 _______________________________________________ Owfs-developers mailing list Owfs-developers@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/owfs-developers
------------------------------------------------------- All the advantages of Linux Managed Hosting--Without the Cost and Risk! Fully trained technicians. The highest number of Red Hat certifications in the hosting industry. Fanatical Support. Click to learn more http://sel.as-us.falkag.net/sel?cmd=lnk&kid7521&bid$8729&dat1642 _______________________________________________ Owfs-developers mailing list Owfs-developers@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/owfs-developers
