Factorio Forums

Got so many assembling machines, how to know what an assembling machine is producing.(is there any option/mod to enable this)

BTW, how to leave sign/note on the map?

Press the "Alt" key to see more details, including what recipe a machine is set to, the contents of chests, filters on smart inserters, etc.
For leaving notes on maps - you can use rails as described here: https://forums.factorio.com/forum/vie ... 46&p=66171 , or put one straight rail with a train stop, name the train stop what you wish the note to be, then remove the rail - train stop names appear on the map (in closer zooms).

Sign/note, with a train stop.

If your output goes on a belt, just a look at the belt. else, [Alt] allows you to see what's on smart inserters conditions, chests contents, and what's being smelted in your furnaces. [Edit] and on your assembling machines