RV-3029 Datasheet, PDF (25/67 Pages) MICORO CRYSTAL SWITZERLAND – DTCXO Temperature Compensated Real Time Clock

Micro Crystal
DTCXO Temperature Compensated Real Time Clock / Calendar Module
RV-3029
4.2. RESET
A Reset can be initiated by 3 different ways:
• Power On Reset (automatically initiated at power-up)
• Software Reset (can be initiated by software)
• Self-Recovery System Reset (automatically initiated if enabled by Software and possible deadlock is
detected)
4.2.1.POWER-UP RESET, SYSTEM RESET AND SELF-RECOVERY RESET
Power On Reset:
A Reset is automatically generated at Power On. After Power On Reset has been executed, bit 5 “PON” in Register
Control_Status is set = “1”, it needs to be cleared by writing = “0”.
System Reset:
A Software Reset can be initiated when the System-Reset command “SysR” is set =”1” (bit 4 in Register
Control_Reset). If a System-Reset is executed, the “SR” Flag (bit 4 in Register Control_Status) is set = “1”, needs
to be cleared by writing = “0”.
It is generally recommended to make a System Reset by Software after power-up.
Note:
Please consider the Register Reset Values shown in section 4.2.2. After a Reset has been executed, Self-
Recovery System “SROn” (bit 4 in Register Control_1) is set = “1” and Self-Recovery INT Enable “SRIE” (bit 4 in
Register Control_INT) is set = “0”.
Self-Recovery System Reset:
A Self-Recovery System Reset will be automatically initiated when the Self-Recovery function is enabled by bit 4
“SROn” in Register Control_1 is set “1” and internally a possible deadlock-state is detected. If a Self-Recovery
System Reset is executed, the bit 4 “SR” in Register Control_Status is set “1” and need to be cleared by writing “0”.
After a Self-Recovery System Reset is executed and Register Reset Values were written, bit 4 “SRF” in Register
Control_INT Flag is set “1” and needs to be cleared by writing “0”.
In case of a Self Recovery System Reset is executed, an Interrupt is available if Self-Recovery-INT function is
Enabled by bit 4 “SRIE” in Register Control_INT is set “1”.
The purpose of the Self Recovery function is to generate an internal System Reset in case the on-chip state
machine goes into a deadlock. The function is based on an internal counter that is periodically reset by the control
logic. If the counter is not reset on time, a possible deadlock is detected and a System Reset will be triggered. The
System Reset is executed latest after 2 temperature- or voltage-monitoring periods defined in Thermometer Period
bit 0 “ThP” in Register EEPROM Control, i.e. latest after 2 or 32 seconds.
Note:
Please consider the Register Reset Values shown in section 4.2.2. After a Reset has been executed, Self-
Recovery System bit 4 “SROn” in Register Control_1 = “1” and Self-Recovery INT Enable “SRIE” in Register
Control_INT = “0”.
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