Spindle Control and Limit switch use same pin?

X-Carve Assembly
1

Here: http://blog.inventables.com/2014/06/shapeoko-upgrade-quite-cut-spindle-with.html it says "Wires from gShield to relay. Red is +5VDC, yellow is signal wire from D12, green is ground. "

But in the instructions: Redirecting… the Z axis limit switch is in D12.

What am I supposed to do? Is the spindle supposed to shut off when it reaches the limit?

2

The instructions from 2014 are referencing GRBL 0.8.

In GRBL 0.9 and later the spindle enable pin was moved to D11.