Printer is unresponsive during M109 command execution

[roboduet]

Is it OK that I can not pause or cancel print during hot end heating up? Seems like the only way to cancel print during M109 is emergency stop button.

[dc42]

That's correct at present. There is work scheduled to allow commands from other input channels to be accepted when M109/M190/M116 are waiting for temperatures to be reached.