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+| Board | Button Interrupt | RS485-Interrupt | RS485/A | RS485/B |
+|-------|------------------|-----------------|---------|---------|
+| 1.0   |               D2 |              D3 |      U7 |      U8 |
+| 2.0   |               D2 |            (D10)|      U8 |      U7 |
+| 2.1   |               D3 |              D2 |      U8 |      U7 | 
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