There are several conditions which the device will go through: a digital reset, putting the registers to their default settings and reloading the OTP.
- A WAKE ping is sent to transition from SHUTDOWN mode or SLEEP mode to ACTIVE mode.
- A WAKE ping is received in ACTIVE mode.
- The CONTROL1[SOFT_RESET] = 1 command is sent in ACTIVE mode.
- A HW_RESET ping is sent under any power mode. This generates a POR-like event to the device. Upon the detection of a HW_RESET ping, the device will turn off all internal blocks except a bandgap for tHWRST duration. Afterward, the device will restart in SHUTDOWN mode.
- Internal power supply faults. See Section 8.3.6.4 for details.
- AVDD UV, DVDD UV is detected.
- A HFO or LFP watchdog fault will reset the digital.
Apart from the full reset cases, the following
conditions will only reset the UART engine. In the device, the FAULT_COMM1[COMMCLR_DET] = 1 will be set.
- A SLEEPtoACTIVE ping is sent to transition from SLEEP mode
to ACTIVE mode.
- The following conditions not only clear the UART engine
and set the [COMMCLR_DET] = 1, they also set
FAULT_COMM1[STOP_DET] = 1 as an indication that an unexpected
UART STOP is detected.
- A SLEEPtoACTIVE ping is sent in ACTIVE mode.
- A COMM CLEAR signal is sent. This is a dedicated
signal to clear the UART engine and instruct the engine to look for
a new start of communication frame. See Section 8.3.6.1.1.1 for more details.