ATMEGA2561V ATMEL [ATMEL Corporation], ATMEGA2561V Datasheet - Page 59

• Manufacturer Part Number: ATMEGA2561V
• Description: 8-bit Microcontroller with 64K/128K/256K Bytes In-System Programmable Flash
• Manufacturer: ATMEL [ATMEL Corporation]

External Reset
2549K–AVR–01/07
Figure 25. MCU Start-up, RESET Tied to V
Figure 26. MCU Start-up, RESET Extended Externally
An External Reset is generated by a low level on the RESET pin. Reset pulses longer
than the minimum pulse width (see Table 26) 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
counter starts the MCU after the Time-out period – t
Figure 27. External Reset During Operation
INTERNAL
INTERNAL
TIME-OUT
TIME-OUT
RESET
RESET
RESET
RESET
V
V
CC
CC
CC
ATmega640/1280/1281/2560/2561
V
V
V
POT
POT
RST
t
TOUT
V
RST
CC
t
TOUT
RST
TOUT
– on its positive edge, the delay
– has expired.
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