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+The construction arm allows a Cubot to read a blueprint from memory and place a [Construction Site](#)
+
+### Interrupt Behavior
+| Value of A | Action | Energy cost | Result |
+| --- | --- | --- | --- |
+| `1` | `PLACE_CONSTRUCTION_SITE` | `10 kJ` | Read a [Blueprint](#) from memory starting at address `X`. The result code is stored in `B` |
+
+If successful, a new [Construction Site](#) will be placed in front of the player.
+
+**Result codes**
+
+* `0x0001`: `ERR_TILE_BLOCKED`
+* `0x0002`: `ERR_NOT_ENOUGH_ENERGY`
+* `0x0003`: `ERR_MEM_READ` (Problem while reading from memory, most likely array out of bounds)
+* `0x0004`: `ERR_INVALID_BLUEPRINT` (Blueprint data does not correspond to any known blueprints)
+* `0x0000`: `OK`
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