The LUTs can be linked by applying a LUT output as input to a different LUT. Linking LUTs can for instance be used to create more complex waveforms, or simply to increase the number of available inputs. When LUTs are connected in cascade the number of inputs is 2N+1 where N is the number of connected LUTs. Linked LUT input is selected by writing the Input y Source Selection bit group in the LUT Control x register (LUTCTRLx.INSELy) to 0x2. The following table shows the corresponding inputs and outputs available for linking.
| LUT | IN[x] | Output from LUT |
|---|---|---|
| LUT0 | x = 0,1,2 | LUT1 |
| LUT1 | x = 0,1,2 | LUT2 |
| LUT2 | x = 0,1,2 | LUT3 |
| LUT3 | x = 0,1,2 | LUT0 |