Falling Trigger selection register (EXTI_FTSR)
| TR0 | Falling trigger event configuration of line 0 |
| TR1 | Falling trigger event configuration of line 1 |
| TR2 | Falling trigger event configuration of line 2 |
| TR3 | Falling trigger event configuration of line 3 |
| TR4 | Falling trigger event configuration of line 4 |
| TR5 | Falling trigger event configuration of line 5 |
| TR6 | Falling trigger event configuration of line 6 |
| TR7 | Falling trigger event configuration of line 7 |
| TR8 | Falling trigger event configuration of line 8 |
| TR9 | Falling trigger event configuration of line 9 |
| TR10 | Falling trigger event configuration of line 10 |
| TR11 | Falling trigger event configuration of line 11 |
| TR12 | Falling trigger event configuration of line 12 |
| TR13 | Falling trigger event configuration of line 13 |
| TR14 | Falling trigger event configuration of line 14 |
| TR15 | Falling trigger event configuration of line 15 |
| TR16 | Falling trigger event configuration of line 16 |
| TR17 | Falling trigger event configuration of line 17 |
| TR18 | Falling trigger event configuration of line 18 |
| TR19 | Falling trigger event configuration of line 19 |
| TR20 | Falling trigger event configuration of line 20 |
| TR21 | Falling trigger event configuration of line 21 |
| TR22 | Falling trigger event configuration of line 22 |
| TR23 | Falling trigger event configuration of line 23 |