On Fri, 2012-02-03 at 11:36 +0100, Michael Haberler wrote: > Am 03.02.2012 um 04:50 schrieb Kirk Wallace: > > > I am able to modpoll the proper registers now, but I have a problem > with > > Do you mean 'modpoll the proper registers' to mean 'read several > holding registers in one operation'? > > If so: I had that problem with the Toshiba VFS-11. See the note in my > driver at > http://git.mah.priv.at/gitweb/vfs11-vfd.git/blob/refs/heads/f12-prod:/vfs11_vfd.c#l216 > > - Michael
Yes, I meant I could get modpoll to read multiple registers as expected and according to a plan based on the register list (after getting the proper list). Of course with modpoll, I got errors when my base address and count pushed the end of the read into registers that do not exist. Also the SJ200 manual indicates that no more than four holding registers can be accessed at a time. The SJ200 must have a very small communication buffer, maybe due to having to deal with a tiny processor in the operator unit that occupies the Modbus port. With more experimentation I was able to get my comp to read even numbers of registers, with the last byte missing. This leads me to believe I have a endian or data type problem, so I'll need to learn more about the types used in modbus.c and types in general, or just read each register one at a time. I often can learn just enough about a sample C file to tweak some key words to get something that works, but this may not be the case for me here. Thanks Michael for your all the work you do on LinuxCNC. -- Kirk Wallace http://www.wallacecompany.com/machine_shop/ http://www.wallacecompany.com/E45/index.html California, USA ------------------------------------------------------------------------------ Try before you buy = See our experts in action! The most comprehensive online learning library for Microsoft developers is just $99.99! Visual Studio, SharePoint, SQL - plus HTML5, CSS3, MVC3, Metro Style Apps, more. Free future releases when you subscribe now! http://p.sf.net/sfu/learndevnow-dev2 _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
