Am 27.06.2016 um 18:47 schrieb samuix: > Hi, > with the help of digitemp_DS9097U we found following: > In the module ow_ds9097u.c is a parameter missing, we modified a line and it > seems to work..... > we patched the module locally: ow_ds9097u.c row:594 : > // default PDSRC = 1.37Vus > RETURN_BAD_IF_BAD(DS2480_configuration_write(PARMSEL_SLEW, > PARMSET_Slew1p37Vus, > in)) ; > The value (PDSRC=1.37V/µs) is mentioned in the specification > :http://pdfserv.maximintegrated.com/en/an/AN192.pdf > <https://deref-gmx.net/mail/client/dereferrer/?redirectUrl=http%3A%2F%2Fpdfserv.maximintegrated.com%2Fen%2Fan%2FAN192.pdf> > after make the owserver found the sensors :-) > Ah, nice. That explains why it works for me. I have a very short bus, only a single DS18S20 on a short stub.
If you have a long cable attached, setting a lower slew rate may be needed. See the DS2840B datasheet, page 15. https://datasheets.maximintegrated.com/en/ds/DS2480B.pdf As this is something which changes with the bus cable, we need to have it tuneable. For the DS2490, OWFS autotunes it. Thanks for uncovering the problem. May we come back to you when we have an autotuning solution? Kind regards Jan ------------------------------------------------------------------------------ Attend Shape: An AT&T Tech Expo July 15-16. Meet us at AT&T Park in San Francisco, CA to explore cutting-edge tech and listen to tech luminaries present their vision of the future. This family event has something for everyone, including kids. Get more information and register today. http://sdm.link/attshape _______________________________________________ Owfs-developers mailing list Owfs-developers@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/owfs-developers
