3D Print Power off and continue to print while power on

Hi:
Recently, i found others 3D Printers could finish some function,like this : 3d printer is working fine ,but unfortunately the power off, some times later,3d printer could contine to print when power on . this is so cool ,but could you tell me how to achieve this function use smoothie board.
now ,i think if smoothie board could remeber the gcode and it’s print line before power off , i want to try .
could you help me ? thanks for your answer.

Imported from wikidot

Can you tell us what printer implements that ?

It sounds horribly difficult to implement. I guess if your printer had a bit of backup power, like a battery, you could have it pause when it detects the power outage ( Smoothie supports that ) but it’d need to still be able to move the motors for a few seconds, the time for Smoothie to properly stop moving. And it needs to keep logic power during all of the outage.

A bit of backup power ? yes,it sounds good. but ,if i don’t have a battery , can i remeber the gcode line to continue print? In other words ,what’s meaning of M110, how to use it?

If there is a power outage, you will loose the current position, as that is stored in ram. Therefore you won’t be able to automatically restart the print.
If you happen to know what line of gcode the print stopped at, *and* you homed before printing, you can possibly use a combination of G92 and M110 to restart, but there is no garantee it’ll give good results.