[gnea/grbl-Mega Issue#143] Any sence for ENABLE_SAFETY_DOOR_INPUT_PIN ?

I see the following lines in config.h

“
// This option causes the feed hold input to act as a safety door switch. A safety door, when triggered,
// immediately forces a feed hold and then safely de-energizes the machine. Resuming is blocked until
// the safety door is re-engaged. When it is, Grbl will re-energize the machine and then resume on the
// previous tool path, as if nothing happened.
#define ENABLESAFETYDOORINPUTPIN // Default disabled. Uncomment to enable.
“
But ENABLESAFETYDOORINPUTPIN is not used in other files. It is useless.

At the same time I have this kind of message

> Grbl 1.1r [‘$’ for help]
> [MSG:Check Door]

It appears every time when I connect MEGA board with RAMPS 1.6 on top of it. This error not happens when I connect only MEGA without RAMPS on it.

What should I do to get it fixed?

When RAMPS on top of MEGA in console it reacts only on “?” command. It does nothing when I enter “$$”, “~”, “$#” and so on.