On Monday 28 November 2005 08:14 pm, Paul Alfille wrote: > On Monday 28 November 2005 02:53 pm, Dave wrote: > > 2) When using cascaded DS2409 lan couplers/switches, how do all the > > attached 1-wire device appear in the OWFS? Does it use cache to > > transparently "flatten" it all out? Can we see the DS2409 hierarchy in > > the OWFS? > > The hierarchy is preserved. Each DS2409 has two subdirectories (in addition > to a number of other files) called main and aux. Those directories in turn > show the filesystem view of that branch. The switching the the correct > branch and all is done transparently. > > Paul Alfille > I should add that the only limit to the depth of branching allowed is the maximum length of the path name in your operating system -- something like 2000 characters I believe. That gives a depth of around 100. Not 100 couplers, but branches 100 couplers deep.
I suspect the electrical constraints and transmission line properties are more stringent. Also the switching times and bus search times would probably make deep branching difficult. One other aspect to the DS2409 couplers -- they are poorly supported by the LINK adapters. Let me backtrack. In pure DS9097U emulation (which is what OWFS currently does), the LINKs have no problems with the couplers. Howevers, when used in their ascii mode (which we will support as an option in the future to get at their other properties like LinkLocator) they don't support couplers. They don't support branch selection for searches. The LINK people (William Farmer) have a product that gives a flat hierarchy with electrical segmentation, which they feel is a better approach. Paul Alfille ------------------------------------------------------- This SF.net email is sponsored by: Splunk Inc. Do you grep through log files for problems? Stop! Download the new AJAX search engine that makes searching your log files as easy as surfing the web. DOWNLOAD SPLUNK! http://ads.osdn.com/?ad_id=7637&alloc_id=16865&op=click _______________________________________________ Owfs-developers mailing list Owfs-developers@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/owfs-developers
