Used with my Nophead Dibond Mendel90 kit which now has a Panelolu2 from Think3DPrint3D. M206 working and shows -ve and +ve coordinates. Main contribution from ICare Uploaded to GitHub so that this can be shared easily.
Alan 2nd August 2013
Changes following input from Nophead which have enabled easier implementation of Panelolou2 using Arduino V1.0.1. Note that Arduino IDE will need LiquidTWI2 in Arduino libraries folder. (Downloaded from here: https://github.com/lincomatic/LiquidTWI2
Alan 17th October 2013