On Sat, Jan 24, 2009 at 5:12 AM, Leslie Newell <[email protected]> wrote: > I have to agree. There are so many times where this is useful or even > vital for a particular job. I understand the difficulties involved in > stopping halfway through a move but would it be possible to have an > option to stop at the end of the current move (or the end of the > lookahead queue) then allow jogging? All emc has to do then is record > the current position. Once you have finished jogging emc can move back > to the recorded position and carry on. The same would apply for a tool > change. > > Les > > Steve Blackmore wrote: >> The encoder support in EMC is very good, however the pause leaves a lot >> to be desired compared to Mach. >> >> It's not possible to Jog during a feed hold or pause in a program to >> zero a tool or clear swarf. >>
Would it be possible to jog an axis while paused with a hal module and pyVCP? If the Z axis is to be jogged, and STEPGEN is used: The HAL module would have 3 float outputs (POS-OUT, FB-OUT, DELTA), 2 float inputs (POS-IN, FB-IN), 3 bit inputs (enable, plus, minus), and two parameters, IN_SCALE and OUT_SCALE. These parameters might be set using [AXIS_2]INPUT_SCALE and [AXIS_2]OUTPUT_SCALE. In pyVCP, there would be a checkbox and two buttons (Enable, +, -) and a numeric display for a float. These would connect to enable, plus, minus, and DELTA, respectively, on the HAL module. POS-IN and FB-OUT connect to MOTOR-POS-CMD and MOTOR-POS-FB for AXIS.2, POS-OUT and FB-IN connect to to POSITION-CMD and POSITION-FB for STEPGEN.2 During normal operation, FB-IN and POS-IN are copied to FB-OUT and POS-OUT every cycle and DELTA is set to zero. While Enable is checked, FB-IN and POS-IN are not copied. Instead, the bit inputs plus and minus, along with OUT_SCALE, are used to change the value on CMD-OUT. FB-IN is subtracted from FB-OUT, and the difference is written to DELTA. When Enable is un-checked, FB-IN and POS-IN are copied to FB-OUT and POS-OUT every cycle. Caveats --If the axis is not placed very close to where it was to begin with, the user will get a following error. --No checks to ensure emc is paused to begin with, or any way to keep it paused while this module is enabled. --There is nothing to stop the operator from moving too far, either tripping limit switches or gouging the part. Would something like this work? Mark ------------------------------------------------------------------------------ This SF.net email is sponsored by: SourcForge Community SourceForge wants to tell your story. http://p.sf.net/sfu/sf-spreadtheword _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
