XX  XX  XX  XX    3 ^
                    |
XX  XX  XX  XX    2 | Height
                    |
XX  XX  XX  XX    1 v
          ← <>[]
            {}
   2       1
<----Width--->

The ASCII-picture above represents the farm.

• XX: sapling
• : empty block
• <>: robot
• []: chest
• {}: charger
• The ← shows robot's facing.

Download the program on the robot and type edit /usr/bin/lumber.lua to edit settings.

You need to change W and H to the values that are calculated according to the picture above.

The INTERVAL settings makes a robot wait a certain time before it'll begin the next cycle. If the interval is set to false, robot will only wait until fully recharged.

Robot will also drop the tool in the chest under it when it completes a cycle, unless the DROPTOOL setting is set to false. This could be used to recharge or repair the tool.

The tool is an axe that can chop the whole tree, not only one wood block.

You also need to insert some saplings in the bottom-right slot of robot inventory, and a log in the previous one. Otherwise the program won't be able to distinguish a sapling from a log, and so the robot won't chop the trees.

This program uses the CC0 1.0 license, see the LICENSE file for more details about the license.