I think it is possible to make the hostmot2 resolver module work as an absolute encoder. The combination of the existing POSITION_FILE and HOME_ABSOLUTE_ENCODER seem to be enough.
As far as I can see so far the resolver module will have to infer the position read from the position.txt file by being netted to the joint.N.pos-fb (or pos-cmd) HAL pin. Unless there is a better way? These pins seem to hold identical values which correspond to (text_file_value - current_resolver_pos) but I need to study the values as they change during the first few servo-thread iterations. The resolver module should be able to work out the best-fit number of complete turns to match the text file value and set its position output accordingly. I think that this will either leave the joint.N.pos-cmd and pos-fb pins showing zero or double the position (until homing happens). But again experiment will answer the question. I don't know if this is a problem. I think if the new HAL pin is unconnected then things will behave exactly like they currently do. What happens if they are connected but there is no position.txt file is yet to be determined. Any thoughts? I am already doing something very like this with a user space component and some sum2 modules. But it is clunky and if I do lose position then the system f-errors on homing (maybe solvable by changing the thread order of the sum2, I haven't experimented) -- atp "A motorcycle is a bicycle with a pandemonium attachment and is designed for the especial use of mechanical geniuses, daredevils and lunatics." — George Fitch, Atlanta Constitution Newspaper, 1916 ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, Slashdot.org! http://sdm.link/slashdot _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
