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External reset, Atmega162/v – Rainbow Electronics ATmega162V User Manual

Page 48

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48

ATmega162/V

2513E–AVR–09/03

Figure 22. MCU Start-up, RESET Tied to V

CC

.

Figure 23. MCU Start-up, RESET Extended Externally

External Reset

An External Reset is generated by a low level on the RESET pin. Reset pulses longer
than the minimum pulse width (see Table 18) will generate a Reset, even if the clock is
not running. Shorter pulses are not guaranteed to generate a Reset. When the applied
signal reaches the Reset Threshold Voltage – V

RST

on its positive edge, the delay

counter starts the MCU after the Time-out period t

TOUT

has expired.

Figure 24. External Reset During Operation

V

RESET

TIME-OUT

INTERNAL

RESET

t

TOUT

V

POT

V

RST

CC

RESET

TIME-OUT

INTERNAL

RESET

t

TOUT

V

POT

V

RST

V

CC

CC