Datasheet

Value Description
00 The low level of INT0 generates an interrupt request.
01 Any logical change on INT0 generates an interrupt request.
10 The falling edge of INT0 generates an interrupt request.
11 The rising edge of INT0 generates an interrupt request.
Atmel ATmega644A [DATASHEET]
Atmel-42716C-ATmega644A_Datasheet_Complete-10/2016
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