TIM_START
CSR_WRITE_1(sc, STAT_TX_TIMER_CTRL, TIM_START);
CSR_WRITE_1(sc, STAT_LEV_TIMER_CTRL, TIM_START);
CSR_WRITE_1(sc, STAT_ISR_TIMER_CTRL, TIM_START);
CSR_WRITE_1(sc, B2_IRQM_CTRL, TIM_START);