{"action":"created","issue":{"url":"https://api.github.com/repos/grbl/grbl/issues/801","labels_url":"https://api.github.com/repos/grbl/grbl/issues/801/labels{/name}","comments_url":"https://api.github.com/repos/grbl/grbl/issues/801/comments","events_url":"https://api.github.com/repos/grbl/grbl/issues/801/events","html_url":"https://github.com/grbl/grbl/issues/801","id":106422384,"number":801,"title":"G28 (and probably G30) ignore axes","user":{"login":"nathanwosborn","id":8643532,"avatar_url":"https://avatars.githubusercontent.com/u/8643532?v=3","gravatar_id":"","url":"https://api.github.com/users/nathanwosborn","html_url":"https://github.com/nathanwosborn","followers_url":"https://api.github.com/users/nathanwosborn/followers","following_url":"https://api.github.com/users/nathanwosborn/following{/other_user}","gists_url":"https://api.github.com/users/nathanwosborn/gists{/gist_id}","starred_url":"https://api.github.com/users/nathanwosborn/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/nathanwosborn/subscriptions","organizations_url":"https://api.github.com/users/nathanwosborn/orgs","repos_url":"https://api.github.com/users/nathanwosborn/repos","events_url":"https://api.github.com/users/nathanwosborn/events{/privacy}","received_events_url":"https://api.github.com/users/nathanwosborn/received_events","type":"User","site_admin":false},"labels":[],"state":"open","locked":false,"assignee":null,"milestone":null,"comments":4,"created_at":"2015-09-14T20:34:41Z","updated_at":"2015-09-15T01:57:11Z","closed_at":null,"body":"The spec says (in part):\r\n\r\nG28 - makes a rapid move from the current position to the absolute position of the values in parameters 5161-5166.\r\n\r\nG28 axes - makes a rapid move to the position specified by axes including any offsets, then will make a rapid move to the absolute position of the values in parameters 5161-5166 for axes specified. Any axis not specified will not move.\r\n\r\nG28.1 - stores the current absolute position into parameters 5161-5166.\r\n<end of spec>\r\n\r\nSo \"G28 Z0\" should move only the Z axis to the position specified by G28.1.  As it stands any axes specified are ignored and all axes (x,y and z) move.  I think this may have resulted in the confusion over whether G28.1 should take axes parameters.\r\n\r\nThis arose because the post that Fusion 360 uses (grbl.cps) uses \"G28 G91 Z0\" to retract at the end of a program and then \"G28 G91 X0 Y0\" to move x and y.  The idea is to retract z before moving x and y.\r\n\r\nI have replaced grbl.cps with a custom post that uses \"G53 G90 Z-5\" to retract z. But we should still fix it."},"comment":{"url":"https://api.github.com/repos/grbl/grbl/issues/comments/140252319","html_url":"https://github.com/grbl/grbl/issues/801#issuecomment-140252319","issue_url":"https://api.github.com/repos/grbl/grbl/issues/801","id":140252319,"user":{"login":"109JB","id":10978476,"avatar_url":"https://avatars.githubusercontent.com/u/10978476?v=3","gravatar_id":"","url":"https://api.github.com/users/109JB","html_url":"https://github.com/109JB","followers_url":"https://api.github.com/users/109JB/followers","following_url":"https://api.github.com/users/109JB/following{/other_user}","gists_url":"https://api.github.com/users/109JB/gists{/gist_id}","starred_url":"https://api.github.com/users/109JB/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/109JB/subscriptions","organizations_url":"https://api.github.com/users/109JB/orgs","repos_url":"https://api.github.com/users/109JB/repos","events_url":"https://api.github.com/users/109JB/events{/privacy}","received_events_url":"https://api.github.com/users/109JB/received_events","type":"User","site_admin":false},"created_at":"2015-09-15T01:57:11Z","updated_at":"2015-09-15T01:57:11Z","body":"This is not correct for LinuxCNC.  the following command will have the results listed below in LinuxCNC\r\n\r\nG28 Z0 (Rapid first to Z=0, then move all axes to that specified in G28.1) \r\n\r\nThis is the same as the NIST standard"}}