alternate function register 2
| BK2INE | BRK2 BKIN input enable |
| BK2CMP1E | BRK2 COMP1 enable |
| BK2CMP2E | BRK2 COMP2 enable |
| BK2CMP3E | tim_brk2_cmp3 enable |
| BK2CMP4E | tim_brk2_cmp4 enable |
| BK2CMP5E | tim_brk2_cmp5 enable |
| BK2CMP6E | tim_brk2_cmp6 enable |
| BK2CMP7E | tim_brk2_cmp7 enable |
| BK2CMP8E | tim_brk2_cmp8 enable |
| BK2INP | TIMx_BKIN2 input polarity |
| BK2CMP1P | tim_brk2_cmp1 input polarity |
| BK2CMP2P | tim_brk2_cmp2 input polarity |
| BK2CMP3P | tim_brk2_cmp3 input polarity |
| BK2CMP4P | tim_brk2_cmp4 input polarity |
| OCRSEL | ocref_clr source selection |