This is a fork of Grbl 1.1f for the MidTBot.
The official Grbl Repo by Sungeon Jeon is https://github.com/gnea/grbl.
This fork turns on the CoreXY functions, sets the correct defaults and adds pen up/down control of a hobby servo for the pen.
Any work coordinate system Z>0 is pen up. Any work coordinate system Z<=0 is pen down.
The MidTBot is documented on the http://www.buildlog.net/blog/?s=midtbot. Please ask all question on the blog.
Note: This needs to be installed as an Arduino library. See the Grbl wiki pages on how to do that.