This is a question,not an issue

[lafar6502]

I tried compiling the original grbl sources (https://github.com/grbl/grbl) with Arduino IDE 1.0.6 for Mega2650 board and everything went smoothly - cleanly compiled and downloaded to the board, but serial communication did not work in any baud rate (tested with Grbl Controller). Then I took your version (Grbl9fMega2560), did the same and with one minor glitch it compiled and downloaded. This time communication works OK on 115200 baud. Now the question: WHY?! Why it no work in the original repo? What's the secret modification you had to make to get it to run?

PS thanks for making mega2560 versions available