DBG APB freeze register 1
| DBG_TIMER2_STOP | Debug Timer 2 stopped when Core is halted |
| DBG_TIM3_STOP | TIM3 counter stopped when core is halted |
| DBG_TIMER6_STOP | Debug Timer 6 stopped when Core is halted |
| DBG_TIM7_STOP | TIM7 counter stopped when core is halted |
| DBG_RTC_STOP | Debug RTC stopped when Core is halted |
| DBG_WWDG_STOP | Debug Window Wachdog stopped when Core is halted |
| DBG_IWDG_STOP | Debug Independent Wachdog stopped when Core is halted |
| DBG_I2C1_STOP | I2C1 SMBUS timeout mode stopped when core is halted |
| DBG_LPTIM2_STOP | Clocking of LPTIMER2 counter when the core is halted |
| DBG_LPTIM1_STOP | Clocking of LPTIMER1 counter when the core is halted |