 |
Electronic Components Datasheet Search |
|
|
Electronic Components Datasheet Search |
|
ST6215C Datasheet(PDF) 26 Page - STMicroelectronics |
|
||||||||||||||||||||||||||||||
ST6215C Datasheet(HTML) 26 Page - STMicroelectronics |
|
|
26 / 105 page 
ST6215C/ST6225C 26/105 RESET (Cont’d) 5.3.4 Watchdog Reset The MCU provides a Watchdog timer function in order to be able to recover from software hang- ups. If the Watchdog register is not refreshed be- fore an end-of-count condition is reached, a Watchdog reset is generated. After a Watchdog reset, the MCU restarts in the same way as if a Reset was generated by the RE- SET pin. Note: When a watchdog reset occurs, the RESET pin is tied low for very short time period, to flag the reset phase. This time is not long enough to reset external circuits. For more details refer to the Watchdog Timer chapter. 5.3.5 LVD Reset Two different RESET sequences caused by the in- ternal LVD circuitry can be distinguished: s Power-On RESET s Voltage Drop RESET During an LVD reset, the RESET pin is pulled low when VDD<VIT+ (rising edge) or VDD<VIT- (falling edge). For more details, refer to the LVD chapter. Caution: Do not externally connect directly the RESET pin to V DD, this may cause damage to the component in case of internal RESET (Watchdog or LVD). Figure 15. Simple External Reset Circuitry Figure 16. Reset Processing ST62xx RESET VDD VDD R C Typical: R = 10K C = 10nF R > 4.7 K INT LATCH CLEARED NMI MASK SET (IF PRESENT) SELECT NMI MODE FLAGS IS RESET STILL PRESENT? YES PUT FFEh ON ADDRESS BUS FROM RESET LOCATIONS FFEh/FFFh NO FETCH INSTRUCTION LOAD PC INTERNAL RESET RESET 2048 CLOCK CYCLE DELAY 1 |
English ▼
Chinese
German
Japanese
Russian
Korean
Spanish
French
Italian
Portuguese
Polish
Vietnamese
