The ACTIVE_TO_WARM sequence can be triggered by
either a watchdog or ESM_MCU error. In the event of a trigger, the nRSTOUT and nRSTOUT_SOC
signals are driven low and the recovery count (register RECOV_CNT_REG_1) increments. Then,
all BUCKs and LDOs are reset to their default voltages. The PMICs remain in the ACTIVE
state.
At the beginning of the sequence the following
instructions are
executed:
//TPS65941120
// Set FORCE_EN_DRV_LOW
REG_WRITE_MASK_IMM ADDR=0x82 DATA=0x08 MASK=0xF7
// Clear nRSTOUT and nRSTOUT_SOC
REG_WRITE_MASK_IMM ADDR=0x81 DATA=0x00 MASK=0xFC
// Increment the recovery counter
REG_WRITE_MASK_IMM ADDR=0xa5 DATA=0x01 MASK=0xFE
Note: The watchdog or ESM error is an indication
of a significant error that has taken place outside of the PMIC. The PMIC does not
actually transition through the safe recovery as with an MCU_POWER_ERR, however, in order
to maintain consistency all of the regulators are returned to the values stored in NVM and
the recovery counter is incremented. If the recovery counter exceeds the recovery count
threshold the resulting RECOV_CNT_INT sends the PMICs to the safe recovery
state.
Note: After the ACTIVE_TO_WARM
sequence the processor is responsible for managing the EN_DRV and recovery counter. At the
end of the sequence the 'FORCE_EN_DRV_LOW' bit is cleared so that the MCU can set the
ENABLE_DRV bit.
Figure 6-4 ACTIVE_TO_WARM Power
Sequence
Note: The regulator transitions do not represent enabling of the regulators but the time
at which the voltages are restored to their default values. Since this sequence
originates from the ACTIVE state all of the regulators are on.